Define the term “Documentation”.
Documentation may be defined as the process of communicating about the system. It is a
process to help users of software and other people to use and interact with system. Effective and
accurate documentation is very necessary for the success of any system. Documentation
becomes part of each step of system development through out the process of system
development even before the documentation starts officially. During the process of system
development, study reports and other necessary information are documented to help people
involved in system development to understand the process. There are many kinds of
documentation namely analysis documentation, design documentation, interface documentation,
internal program documentation and user-oriented documentation. Documentation should not be
seen as a overhead for system development. Rather, documentation has to be seen as an
investment for the development of high quality software.
System Requirements Specification
System requirement specification is a set of complete and precisely stated properties along with
the constraints of the system that the software must satisfy. A well designed software
requirements specification establishes boundaries and solutions of system to develop useful
software. All tasks, however minute, should not be underestimated and must form part of the
documentation.
Requirements of SRS: The SRS should specify only the external system behavior and not the
internal details. It also specifies any constraints imposed on implementation. A good SRS is
flexible to change and acts as a reference tool for system developer, administrator and
maintainer.
Characteristics of a System Requirements Specification (SRS)
1. All the requirements must be stated unambiguously. Every requirement stated has only one
interpretation. Every characteristic of the final product must be described using a single and
unique term.
2. It should be complete. The definition should include all functions and constraints intended by
the system user. In addition to requirements of the system as specified by the user, it must
conform to any standard that applies to it.
3. The requirements should be realistic and achievable with current technology. There is no point
in specifying requirements which are unrealisable using existing hardware and software
technology. It may be acceptable to anticipate some hardware developments, but
developments in software technology are much less predictable.
4. It must be verifiable and consistent. The requirements should be shown to be consistent and
verifiable. The requirements are verified by system tester during system testing. So, all the
requirements stated must be verifiable to know conformity to the requirements. No
requirement should conflict with any other requirement.
5. It should be modifiable. The structure and style of the SRS are such that any necessary
changes to the requirements can be made easily, completely and consistently.
6. It should be traceable to other requirements and related documents. The origin of each
requirement must be clear. The SRS should facilitate the referencing of each requirement for
future development or enhancement of documentation. Each requirement must refer to its
source in previous documents.
7. SRS should not only addresses the explicit requirement but also implicit requirements that may
come up during the maintenance phase of the software. It must be usable during operation
and maintenance phase. The SRS must address the needs of the operation and
maintenance phase, including the eventual replacement of the software.
System Design Specification
The system design specification or software design specification as referred to have a primary
audience, the system implementer or coder. It is also an important source of information for the
system verification and testing. The system design specification gives a complete understanding
of the details of each component of the system, and its associated algorithms, etc.
The system design specification documents all as to how the requirements of the system are to
be implemented. It consists of the final steps of describing the system in detail before the coding
starts.
The system design specification is developed in a two stage process: In the first step, design
specification generally describes the overall architecture of the system at a higher level. The
second step provides the technical details of low-level design, which will guide the implementer. It
describes exactly what the software must perform to meet the requirements of the system.
Tools for describing design
Various tools are used to describe the higher level and lower level aspects of system design. The
following are some of the tools that can be used in the System Design Specification to describe
various aspects of the design.
· Data dictionary
· Database schema
· E-R model
· Security model
· Trade-off matrix
· Decision table
· Timing diagram
· State machine diagram
· Object Interaction Diagram
· Inheritance Diagram
· Aggregation Diagram
· Structure Chart
· Pseudocode
Test Document
During system development, this document provides the information needed for adequate
testing. It also lists approaches, procedures and standards to ensure that a quality product that
meets the requirement of the user is produced. This document is generally supplemented by
documents like schedules, assignments and results. A record of the final result of the testing
should be kept externally. This document provides valuable input for the maintenance phase.
The following is the typical content of Test Design Document:
1. Introduction
Purpose: The purpose of this document and its intended audience are clearly stated.
Scope: Give an overview of testing process and major phases of the testing process.
Specify what is not covered in the scope of the testing such as, supporting or not third
party software.
Glossary: It gives definition of the technical terms used in this document.
References: Any references to other external documents stated in this document
including references to related project documents. They usually refer the System
Requirement Specification and the System Design Specification documents.
Overview of Document: Describe the contents and organization of the document.
2. Test Plan
A test plan is a document that describes the scope, approach, resources and schedule of
intended testing activities. It identifies test items, the features to be tested, the testing tasks, and
the person who will do each task, and any risks that require contingency planning.
2.1. Schedules and Resources: An overview of the testing schedule in phases along with
resources required for testing is specified.
2.2. Recording of Tests: Specify the format to be used to record test results. It should
very specifically name the item to be tested, the person who did the testing,
reference of the test process/data and the results expected by the test, the date
tested. If a test fails, the person with the responsibility to correct and retest is also
documented. The filled out format would be kept with the specific testing schedule. A
database could be used to keep track of testing.
2.3. Reporting test results: The summary of what has been tested successfully and the
errors that still exist which are to be rectified is specified.
3. Verification Testing
3.1. Unit Testing: For each unit/component, there must be a test which will enable tester
to know about the accurate functioning of that unit.
3.2. Integration testing: Integration test is done on modules or sub-systems.
4. Validation Testing
4.1. System Testing: This is the top level of integration testing. At this level, requirements
are validated as described in the SRS.
4.2. Acceptance and Beta Testing: List test plans for acceptance testing or beta testing.
During this test, real data is used for testing by the development team (acceptance
testing/alpha testing) or the customer (beta testing). It describes how the results of such
testing will be reported back and handled by the developers.
User Manual
This document is complete at the end of the software development process.
Different Types of User Documentation
Users of the system are not of the same category and their requirements vary widely. In order to
cater to the need of different class of user, different types of user documentation are required.
The following are various categories of manuals:
• Introductory manual: How to get strted with the system?
• Functional description: Describes functionality of the system.
• Reference manual: Details about the system facility.
• System administrator guide: How to operate and maintain the system?
• Installation document: How to install the system
Q4: Explain the following kinds of information systems: (20 Marks)
Transaction Processing Systems
Businesses offer service and products to the customers. In simple terms, transaction processing
system is an information system that supports business in the delivery of various business
transactions. A transaction processing system records and processes data resulting from
business transaction. Transactions are events that occur as a result of business operations like
transfer of money from one account to another account, purchase of items, etc. Transactions are
basically a series of related operations that must all succeed or fail as a group. A single
transaction of withdrawing money from a bank account actually involves two operations are a
debit to an account and credit to another account. Transactions processing system allows the two
operations to group into a single transaction. When both the operations are successfully
completed, then the transaction is said to be complete. TPS can be classified into the category of
Operation information system. Example can be Sales Transaction Processing System. These
systems are transaction intensive and results of such transaction processing are used to update
various databases like customer databases, inventory databases and accounts receivable
databases. Transaction Processing Systems are also used to make day to day decisions that
control operational processes.
Transaction processing systems (TPS) could be on-line or off-line. In case of On-line Transaction
Processing systems, data is processed by the system immediately after the transaction occurs.
Point of Sale (POS) is a common example of the On-line Transaction Processing System (OLTP).
The following are major characteristics of Transaction Processing Systems :
• Support business operations;
• Focus on data resulting from business transactions; and
• Captures and processes data of business transactions.
Management Information Systems
Management Information System (MIS) is a special kind of information system that helps
managers to take decisions. MIS is tailored to provide specific information to individual managers
for long term and strategic decision-making. MIS is used by the middle and top-management for
their information requirements for decision-making. The use of MIS helps to produce the
information that organizations need to improve decision-making, problem solving, controlling
operations, and creating new products or services. Keeping this in view, a number of
organizations invest in development of a computerized MIS . The focus of MIS is to provide
strategic information required by top-management. Major volume of information for top
management comes from events not directly related to day-to-day business operations.
Therefore, the information from normal reporting systems is found inadequate for managers.
Therefore, special information system is developed for top management to support their activity,
which is not met by other information systems.
The following are the characteristics of Management Information Systems (MIS):
• Provides reports to management usually in semi-structured format ( in detailed, summary, and
exception);
• Usually uses shared database from many sources;
• Often based on management or statistical models;
• Information presented in both textual and graphical forms, but more often in graphical format;
• Provides information on trend analysis, exception reporting and what-if-analysis. It allows the
user to ask questions such as , what if we increase price by 10%, the effect on sales of the
product? If inflation increases by 5 per cent what will be the effect on the sales forecast?
Decision Support Systems
In contrast to other information systems which provide general information about organization’s
performance in fixed format to managers, Decision Support Systems provide information to
managers which will be helpful for them to make decisions. A manager at a higher level needs
adhoc information for strategic planning and control.
Decision Support Systems (DSS) can be defined as a specific class of information systems that
support business and organizational decision-making activities, as needed to managers. A
properly designed DSS is an interactive software-based system intended to help decision makers
compile useful information from raw data, documents, personal knowledge, and/or business
models to identify and solve problems and make decisions.
The following are the major characteristics of Decision Support Systems (DSS):
• Help decision makers to take decisions rather than replace them;
• Use underlying data and models;
• Have little or no reasoning capability;
• Are tailored to directly support decision-making styles of individual managers;
• Support interactive inquires and responses;
• Are used to aid semi-structured or unstructured decisions;
• Produce information on ad-hoc, flexible and adaptable format;
• Information is produced by analysis of operational and external data; and
• Analyses and supports comparison of specific alternative decisions.
Expert Systems
An Expert System is a computer program that simulates the judgment and behaviour of a human
expert or an organization that has expert knowledge and experience in a particular field. Typically,
such a system contains a knowledge base containing accumulated experience and a set of rules
for applying the knowledge base to each particular situation that is described to the program.
Sophisticated expert systems can be enhanced with additions to the knowledge base or to the set
of rules. The expert system is a knowledge-based information system to act as a consultant to the
user. Expert systems are being used in many specialized field like medicine, engineering and
business. An Expert System in the field of medicine can help diagnose illness. Unlike Decision
Support System, an expert System interacts with the user to get input and provides expert advice
on a problem in a specific domain.
Among the best-known expert systems have been those that play chess and those which assist
in medical diagnosis such as Mycin.
The following are the major characteristics of expert systems (ES):
• Captures knowledge and expertise of a problem solver or decision maker and simulates thinking
for those with less knowledge;
• Replaces a human advisor/expert for specific domain of knowledge;
• Its domain of knowledge is narrow;
• Has reasoning and explanation capability;
• Types of problem treated is repetitive; and
• The direction of interaction is from machine to the user.
Monday, September 28, 2009
Saturday, September 26, 2009
SOLID BREAKDOWN
If the solid insulating material is truly homogeneous and is free from imperfections,
its breakdown stress will be as high as 10 MV/cm. This is the 'intrinsic breakdown
strength', and can be obtained only under carefully controlled laboratory conditions.
However, in practice, the breakdown fields obtained are very much lower than this
value. The breakdown occurs due to many mechanisms. In general, the breakdown
occurs over the surface than in the solid itself, and the surface insulation failure is the most frequent cause of trouble in practice.
The breakdown of insulation can occur due to mechanical failure caused by the
mechanical stresses produced by the electrical fields. This is called "electromechanical" breakdown.
On the other hand, breakdown can also occur due to chemical degradation caused
by the heat generated due to dielectric losses in the insulating material. This process is cumulative and is more severe in the presence of air and moisture.
When breakdown occurs on the surface of an insulator, it can be a simple flashover
or formation of a conducting path on the surface. When the conducting path is formed,
it is called "tracking", and results in the degradation of the material. Surface flashover normally occurs when the solid insulator is immersed in a liquid dielectric. Surface flashover, as already mentioned, is the most frequent cause of trouble in practice.
Porcelain insulators for use on transmission lines must therefore be designed to have
a long path over the surface. Surface contamination of electrical insulation exists
almost everywhere to some degree. In porcelain high voltage insulators of the suspension type, the length of the path over the surface will be 20 to 30 times greater than that through the solid. Even there, surface breakdown is the commonest form of failure.
The failure of solid insulation by discharges which may occur in the internal voids
and cavities of the dielectric, called partial discharges, is receiving much attention today, mostly because it determines the life versus stress characteristics of the material. The energy dissipated in the partial discharges causes further eterioration of the cavity walls and gives rise to further evolution of gas. This is a cumulative process eventually leading to "breakdown. In practice, it is not possible to completely eliminate partial discharges, but a level of partial discharges is fixed depending on the expected operating life of the equipment Also, the insulation engineer should attempt to raise the discharge inception level, by carefully choosing electric field distributions and eliminating voids, particularly from high field systems. This requires a very high quality control during manufacture and assembly. In some applications, the effect of the partial discharges can be minimized by vacuum impregnation of the insulation.
For high voltage applications, cast epoxy resin is solving many problems, but great
care should be exercised during casting. High voltage switchgear, bushings, cables,
and transformers are typical devices for which partial discharge effects should be
considered in design.
So far, the various mechanisms that cause breakdown in dielectrics have been
discussed. It is the intensity of the electric field that determines the onset of breakdown and the rate of increase of current before breakdown. Therefore, it is very
essential that the electric stress should be properly estimated and its distribution
known in a high voltage apparatus. Special care should be exercised in eliminating
the stress in the regions where it is expected to be-maximum, such as in the presence
of sharp points.
its breakdown stress will be as high as 10 MV/cm. This is the 'intrinsic breakdown
strength', and can be obtained only under carefully controlled laboratory conditions.
However, in practice, the breakdown fields obtained are very much lower than this
value. The breakdown occurs due to many mechanisms. In general, the breakdown
occurs over the surface than in the solid itself, and the surface insulation failure is the most frequent cause of trouble in practice.
The breakdown of insulation can occur due to mechanical failure caused by the
mechanical stresses produced by the electrical fields. This is called "electromechanical" breakdown.
On the other hand, breakdown can also occur due to chemical degradation caused
by the heat generated due to dielectric losses in the insulating material. This process is cumulative and is more severe in the presence of air and moisture.
When breakdown occurs on the surface of an insulator, it can be a simple flashover
or formation of a conducting path on the surface. When the conducting path is formed,
it is called "tracking", and results in the degradation of the material. Surface flashover normally occurs when the solid insulator is immersed in a liquid dielectric. Surface flashover, as already mentioned, is the most frequent cause of trouble in practice.
Porcelain insulators for use on transmission lines must therefore be designed to have
a long path over the surface. Surface contamination of electrical insulation exists
almost everywhere to some degree. In porcelain high voltage insulators of the suspension type, the length of the path over the surface will be 20 to 30 times greater than that through the solid. Even there, surface breakdown is the commonest form of failure.
The failure of solid insulation by discharges which may occur in the internal voids
and cavities of the dielectric, called partial discharges, is receiving much attention today, mostly because it determines the life versus stress characteristics of the material. The energy dissipated in the partial discharges causes further eterioration of the cavity walls and gives rise to further evolution of gas. This is a cumulative process eventually leading to "breakdown. In practice, it is not possible to completely eliminate partial discharges, but a level of partial discharges is fixed depending on the expected operating life of the equipment Also, the insulation engineer should attempt to raise the discharge inception level, by carefully choosing electric field distributions and eliminating voids, particularly from high field systems. This requires a very high quality control during manufacture and assembly. In some applications, the effect of the partial discharges can be minimized by vacuum impregnation of the insulation.
For high voltage applications, cast epoxy resin is solving many problems, but great
care should be exercised during casting. High voltage switchgear, bushings, cables,
and transformers are typical devices for which partial discharge effects should be
considered in design.
So far, the various mechanisms that cause breakdown in dielectrics have been
discussed. It is the intensity of the electric field that determines the onset of breakdown and the rate of increase of current before breakdown. Therefore, it is very
essential that the electric stress should be properly estimated and its distribution
known in a high voltage apparatus. Special care should be exercised in eliminating
the stress in the regions where it is expected to be-maximum, such as in the presence
of sharp points.
My story is a little graphic, so if you don't like bodily injury, skip this post.
I was driving home from work at 11pm. I had a 97 Eclipse. God I loved that car. Anyway, I lived in the mountians and had to take this small two lane highway home. On the west side of the highway was this huge mountain. On the east side was a river. There were lots of curves, but there was this one straight stretch that was just fast enough to get to 110mph with time to slow down safely. On either end of this straight stretch were 2 sharp 40 mph curves.
The trick was to keep the car going at least 65 through the first two turns. I was going 80, which would have been my fasted time yet. Anyway, I missed the second turn, crashed into the mountain, bounced back through the highway and ended in the river.
Here's where it gets graphic. The driver side window imploded and the airbag pushed the glass into my face. I climbed out of the car. At this point, I could see clearly. I even climbed back down into the car to turn the radio off. I then hitch hiked to a hotel. The front desk agent thought she was a nurse or something, so she bandaged me up. I was pretty messed up. Blood everywhere. Anyway, she tied the bandage around my eyes too tightly, which pushed the glass even further into my eyes.
A few hours later, I finally got to a hospital. It took two surgeons about 8 hours to patch me back together again. The end result, is that the lense in my right eye was removed, the cornea looks like a potato chip, and my iris looks like a tear drop.
I even have a piece of glass in my jaw, because they can't take it out without cuting a nerve.
Good times. Good times.
The trick was to keep the car going at least 65 through the first two turns. I was going 80, which would have been my fasted time yet. Anyway, I missed the second turn, crashed into the mountain, bounced back through the highway and ended in the river.
Here's where it gets graphic. The driver side window imploded and the airbag pushed the glass into my face. I climbed out of the car. At this point, I could see clearly. I even climbed back down into the car to turn the radio off. I then hitch hiked to a hotel. The front desk agent thought she was a nurse or something, so she bandaged me up. I was pretty messed up. Blood everywhere. Anyway, she tied the bandage around my eyes too tightly, which pushed the glass even further into my eyes.
A few hours later, I finally got to a hospital. It took two surgeons about 8 hours to patch me back together again. The end result, is that the lense in my right eye was removed, the cornea looks like a potato chip, and my iris looks like a tear drop.
I even have a piece of glass in my jaw, because they can't take it out without cuting a nerve.
Good times. Good times.
How to improve IT business in India
Q1) 3 - Marks
A tank has two inlets and one out let. one inlet can fill the tank in 8 hours,
another inlet can fill the tank in 6 hours. The outlet can empty the tank in 10 hours.
If all the taps are working together in 1.68 what fraction of the tank will be filled
Q2) 5 - Marks
Tom, Dick and harry are walking to-gether. Tom always tell truth, dick tells truth only sometimes,
harry tell lie always. Dick says "He is harry". Harry the person in the middle is "Tom".
Identify the postion of each person.
Q3) 8 - Marks
A jeweller has two glass cases for displaying the jewels left case and right case.
He has always display 6 of 8 jewels Alchemist, Diamond, garnet, sapphire, ruby, pearl, gold and emerald,
3 in each
1. Alchemist must always be displayed in the Left case
2. Diamond must always be displayed in the right case
3. emerald and sapphire should be displayed together
4. If ruby, then diamondis not displayed together.
5. If garnet then pearl is not displayed together.
1. Which of the following combination is correct in the left case
a) Alchemist, diamond, ruby
b)alchemist, garnet, emerald
2. Which of the following combination is correct in the left case
a)diamond, ruby, pearl
b)alchemist, garnet, pearl
Q4) 5 - Marks
A person wants to travel from A to B a distance of 189 kms.
He can take either the train or coach. He decides to take the coach.
Both the train and coach leave the together. They meet at a point.
The time taken for the person to travel is equal to more distance covered by
him combined for the entire distance. Find the time taken by the Person.
Q5)8 - Marks
Sally and sue want to date joe.
Sally asks joes "Your house number is a square"
Joe answers "Yes"
Sally asks joes "Your house number is greater than 50"
Joe answers "No"
Sally thinks that she has got the number
Sue asks joes "Your house number is a cube"
Joe answers "Yes"
Sue asks joes "Your house number is greater than 25"
Joe answers "No"
Sue thinks that she has got the number
Both sally and sue reach the wrong house.
If joe had anwered the sally's first question wrong
and sue second question wrong and if the joe's house number
is square of the sallys and sue number.
1. What is sallys guess
2. What is sues guess
Q6)8 - Marks
Bill, smith, conners, william are the First names.
Conners, joe, jack, ted are the last names not in the correct order.
They play a game of cards with following rules
First winner will get 10$ from each.
Second winner will get 20$ from each.
Third winner will get 30$ from each.
Fourth winner will get 40$ from each.
After four turns each one is a winner.
Bill is the first winner, williams is the last winner.
If smith had more money in the first round and jack had more money in the last round.
Match their first and Last Names.
Q7) 8 - Marks
There are 6 towns A, B, C, D, E, F, G.
Town A and B are in the same longitude.
Towns D, E are in the same latitude.
E,F are industrail towns. Industrial towns cannot be harbours.
C,G are the harbours
The temperature in the harbour is always 10 degrees less than other towns.
The temperature in the longitude is alway higher than that in the latitude by
16 degress. The temperature in the harbour is less than the industrail towns
The temperature in harbour is 20 degrees.
Find the temperatures of all towns.
A tank has two inlets and one out let. one inlet can fill the tank in 8 hours,
another inlet can fill the tank in 6 hours. The outlet can empty the tank in 10 hours.
If all the taps are working together in 1.68 what fraction of the tank will be filled
Q2) 5 - Marks
Tom, Dick and harry are walking to-gether. Tom always tell truth, dick tells truth only sometimes,
harry tell lie always. Dick says "He is harry". Harry the person in the middle is "Tom".
Identify the postion of each person.
Q3) 8 - Marks
A jeweller has two glass cases for displaying the jewels left case and right case.
He has always display 6 of 8 jewels Alchemist, Diamond, garnet, sapphire, ruby, pearl, gold and emerald,
3 in each
1. Alchemist must always be displayed in the Left case
2. Diamond must always be displayed in the right case
3. emerald and sapphire should be displayed together
4. If ruby, then diamondis not displayed together.
5. If garnet then pearl is not displayed together.
1. Which of the following combination is correct in the left case
a) Alchemist, diamond, ruby
b)alchemist, garnet, emerald
2. Which of the following combination is correct in the left case
a)diamond, ruby, pearl
b)alchemist, garnet, pearl
Q4) 5 - Marks
A person wants to travel from A to B a distance of 189 kms.
He can take either the train or coach. He decides to take the coach.
Both the train and coach leave the together. They meet at a point.
The time taken for the person to travel is equal to more distance covered by
him combined for the entire distance. Find the time taken by the Person.
Q5)8 - Marks
Sally and sue want to date joe.
Sally asks joes "Your house number is a square"
Joe answers "Yes"
Sally asks joes "Your house number is greater than 50"
Joe answers "No"
Sally thinks that she has got the number
Sue asks joes "Your house number is a cube"
Joe answers "Yes"
Sue asks joes "Your house number is greater than 25"
Joe answers "No"
Sue thinks that she has got the number
Both sally and sue reach the wrong house.
If joe had anwered the sally's first question wrong
and sue second question wrong and if the joe's house number
is square of the sallys and sue number.
1. What is sallys guess
2. What is sues guess
Q6)8 - Marks
Bill, smith, conners, william are the First names.
Conners, joe, jack, ted are the last names not in the correct order.
They play a game of cards with following rules
First winner will get 10$ from each.
Second winner will get 20$ from each.
Third winner will get 30$ from each.
Fourth winner will get 40$ from each.
After four turns each one is a winner.
Bill is the first winner, williams is the last winner.
If smith had more money in the first round and jack had more money in the last round.
Match their first and Last Names.
Q7) 8 - Marks
There are 6 towns A, B, C, D, E, F, G.
Town A and B are in the same longitude.
Towns D, E are in the same latitude.
E,F are industrail towns. Industrial towns cannot be harbours.
C,G are the harbours
The temperature in the harbour is always 10 degrees less than other towns.
The temperature in the longitude is alway higher than that in the latitude by
16 degress. The temperature in the harbour is less than the industrail towns
The temperature in harbour is 20 degrees.
Find the temperatures of all towns.
Infosys (comatibility)
1. at each odd year 25 % rise and at each even year
20% fall. then after
10 years what will be there ,a rise or a fall
ans:no rise or fall 3
marks
2. there is a road with length 36 miles.from the one
end, one girl and
from the other a boy starts on a bike towards each
other , with the speed
of 6 miles per hour.when the girls starts one pegion
starts with her at
18 miles per hr speed, meets the boy and then comes
back to the girl.
calculate the total distance travelled by the
pegion.(it doesn't take any
rest.) 3
marks
ans:54 miles
3.a rope of 20 m is cut randomly in 2 pieces such that
they are the
perimeters of the sruare.
1]what is the probability that the area of the bigger
square is 9 m2 or
greater than that.
2]what is the proabibilty that the adddtion of the
areas is 20.5 m2 or
gereater than that.
4marks
4.between A and B stations S (NAME) train travels.it
stars at 9 am then
it reaches b after 3 days 9.30 am. now if such S train
starts from B to A
then , how many S trains does it meet till it
reaches station B ?
ans:7 4 marks.
5.H,W and L (names starting with these letters)are
taking part in one
quiz where 30 questions are asked.there were 45
correcxt answers, amongst
them W answers 55 % that of H.the correct answers
given by the W & L
are 1.25 times that given by H. then the correct
answers given by each
are?(the name of the anchor was also starting with the
letter H and hence
added confusion). 6 marks
ans:20,11,14
6.some lenthy proablem....... with statemnts revealing
the conditions.
green red
and ... houses. 5 neighbours , with different
nationality, different pets
and.....
statements. 6 mark
7.there are 1-82 houses in one colony. i wish to find
out the house no. of
my friend who has newly shifted there. i asked him 3
questions. the answer
may be yes/no. u can find the correct house no.
1]is the noumber above 41?
2]is it divisible by 4?
3]is it perfect square?
ans:64 6 marks
8. three girls r there . to find ut their ages i asked
the questions. one
of them always lies, and other 2 speak truth.
some statements........
then what r the ages. 8 mark.
ans:mostly 26 23 22
9. 3 tribes........... condiion for marriages......
8 mark
this is the Infosys paper at REC TRICHY. 96 were
>shortlisted.
>
results have to come.......
in all 9 questions:
>(1hour ) 50 marks
>Some Question are incomplete soory for that.as By
>the
>time i wrote them down ,i forgot some of them.
>
>Questions
1> there are 111 players participating in atennis
match.Each match uses a new ball.
The loser of each match is eliminated from the
competiton.Find the number of balls used inthe
tennis
compettion.
>ans: 110
>
2) a spider makes a web over a 10 square inch window
> frame. each day it make sthe web twice it has made
>the
>previous day.
>the spider completes the web in 30 days. calculate
>the
>amount of time taken if two spiders are spiining the
>web over the same window.
>(Assuming that each spider completes the work in an
>indepedent manner)
>ans: 29 days
3)Timothy has a stock of ties.consisting of 17 blue
>ties,11 yelow ties.34 orange,9violet and 2 black
>ties.
>the room in which the ties are kept is dark.find
>outhe
>minimum number of ties with timothy should take out
>of
>the room
>so that he has atleast two ties of the same color.
>Ans: 6
>
>4)in a company of 24900 employee,45% of the
>employess
>read Daily.
>60% read Courier,and 40% read Inquirer.
>15% read both Daily and courier
>25% read both Daily and Inquirer
>35% read both inquirer and courir
>while 10% read all the three.
>a) find out how many read daily only?
>b) find out howmany read inquirer only ,courir only
>c) how many dont read newspaper at all
note: it's easy to do in %form , write the answer in
percent
>5)at sabina park ,in a match between india and
>westindies
>the three indian bowlers showed a marvelles
>performance.
>bedi ,prassna and vekatraghvan. find out from the
>condition how many wickets did each score
>conditon 1:
>either bedi took allthe five wicket or prassana took
>3
>wickets
>conditon 2:
>either there was a runout or prassna took one more
>wicket than bedi
>conditon 3)
>the sum of bedi and twice that of prassana is one
>more
>than thrice venkatraghvan
>
> ans :
bedi- 2 wickets
prasana- 4 wickets
venkata - 3 wickets
1 runout
>6) there were two friends.kamal and sikandar both
>were
>talking to each other.
>kaml wanted to ask the age of sikandars 3 children.
>they had the following conversation
>sikandar: the product of their ages is 36
>kamal: i dont have caomplete info abouthis
>tell me something more
>sikandar:the sum of thier ages is equal to u r age.
>kaml: i still cant guess it
>sikandar:my son is more than one year old from both
>my
>daughters.
>
>find the age of the three children
>ans:9 2 2
>
>7)there was a burglary in a neighbourhood. Five
>elderly gentleman used to live in the neighbourhood.
>sherlock holme had come to investigate the
>burglary.he
>had the following facts derived from the
>conversation
> from the five men . Mr black,mr Green,Mr brown,Mr
>grey.
>Mr Plumb
>find their age and names of thier homes.
> conditions:
>A)the 56 and 58 dont live inthe oak house
>b) Mr green is older than mr black
>c) Mr
>
>8) identify the apperance of culprit in the robbery.
>acoording to the foloowuing conditon
>acoording to the guard ,the culprit had blue
>eyes,tall
>,wore a vest and hat
>acoording to the cashier ,the culprit had dark
>eyes,short,wore a vest and hat.
>acording to the secretary,the culprit had green
>eyes,was medium short,wore a raincaot and no hat
>acoording to the director ,the culprit had gray
>eys,was tall , didnot wear a vest but had a hat.
> After the detaild enquiry ,it was found that
>witnesses provided exactly one detail correctly.
>while the atleast one witness provided the correct
>detail oft he culprit.
>Give the appearance of the culprit.
ans : blue eyes,short, wore a raincoat without hat
>
>9) Questin on seating arrnagement from barrons
>there are 10 people:- 5 male L M,N,P,Q AND 5 FEMALE
>U,V,W,S,T
>ALL ARE MARRIED. THAT IS THERE ARE 5 COUPLES.
>they are invbited to a partyy where they are to be
>seated in a row having 10 seat.
>the men ae to occupy the odd numbered seats.while
>the
>women the even numbered seats.
>a) the man whom the woman are married to ,should sit
>at right side of her husband.
>b) Q is Vs husband
>c)
>d)
>
>
>five question based on the above 5-6 conditions.
>
>
ans : i'm not sure the last one..
a. d
b.e
c- c
d: ......
>after this there was an esay writin on :15mins
>"IT IN ENTERTAINMENT INDUSTRY"
>OR
>" COST OF QUALITY CONTROL
Infosys paper held on 4th august in N.I.T.Calicut.
1. There are three tins each one having two boxes.
One tin contains red balls in the two boxes. The
second tin contains blue balls in the two boxes.
The third one contains red balls in one box and blue
balls in another box. Three labels are prepared “red
–red”, ”blue-blue” and “red-blue”. The labels are
fixed randomly on the three boxes. What is the
probability that only one label showing wrong
information?
Ans: 0.
2. In one family there are some boys and some girls.
Each boy has as many brothers as his sisters. And
each girl has as many sisters as the half of her
brothers. How many boys and how many girls are there?
Ans; boys 4,girls 3;
3. In a birthday party there are total 11. Each one
shook his hand with another one only once. Then what
is the total number of shake hands?
Ans: 55.
4.One man is traveling with a constant speed. Due to
consumption of energy the distance traveled per hour
is decreasing same amount every hour. He traveled 135
miles in first two hours. And in the next two hours
he traveled 104 miles. What are the distances he
traveled in the first and the last (fourth) hours?
Ans: 571/8, 385/8
5.One problem with some description about a circus.
The answer is
Ans : BALU.
6. There are two types of tea powders. One costs
5Rs/Kg. And another one costs 3Rs/Kg. 40 Kg of the
mixture is sold at 6Rs/Kg. The profit is 100/3
percent. What are the amounts of tea powders
individually?
Ans: 30Kg,10Kg.
7. one problem with venndiagram about some people
listening to radio stations.
The answer is 400.
INFOSYS 2002 ANNA UNIVERSITY 1/8/2002
Analytical paper(Duration:60 min)
1. In a singles tennis tournament,111 players are
participating.
For each game they will use a new ball.If any player
looses his match,he will be rejected from the
game.then,how many balls are required for the entire
game in order to find out the winner.
(3 marks) 110
2.In a rack there are some ties of different colurs as
follows.
17 green, 11 yellow, 9 blue, 2 orange,7 red.
In dark,how many ties should we extract in order to
have two ties of same colour?
(4 marks)(6)
3.In a company there are 29060 employees.
60%read Daily news.
45% read Indian express.
40% read times of india.
25% read both hindu& indian express.
30% read both indian express and times of india.
10%read both hindu and times of india.
5%read all the paers.
then find
a. How many read only hindu?
b.How many read only indian express and times of
india?
c.How many do not read news paers at all?
(4 marks)
4.one spider is spinning an area of window.It takes 30
days to complete the entire frame provided the
condition is it will spin the same area in the next
day as that of the previous day.
If 2 spiders do this work,then how many days will
those take provided the area spinned by one spider is
equal to that of the other.
(29 days)(4 marks)
5.There are 5 persons lying in one cottage area.
mr.brown, Mr.green, Mr.grey, Mr. plumb, Mr.blue
There are some clues were given about their living
areas and ages.
At last we have to find out their respective ages and
living areas.(GRE analytical type)
(8 marks)
6.Mr.Tom has 3 children.The conversation between him
and his friend George was going like this.
Tom: product of their ages is 36.
The son is elder than each of his sisters by more than
one year.
Can u find their ages?
(4,3,3)(4 marks)
7.The seating arrangement in a theatre is given by
means of some clues.
There are 5 men(l,m,n,p,q) and 5 women(s,t,u,v,w).
Conditions:
1. men will sit in the odd numbered seats.
2......(GRE analytical type)
(8 marks)
8.There was a cricket match and the description of the
no. of wickets taken by 3 plaers b,v,p are as follows.
Either B takes 5 wickets and v takes 3 or p takes a
wicket more than v.
Either B takes half of total wickets or One player is
run out.
Using these, find out the no.of wickets taken by each
player.
(6 marks) ans:4,3,2
9.Gre type like if 2 of 4 say lies then find the
correct one provided the clues given by each of them.
(8 marks) ans:Guard
The other paper is on english comprehension.
(Time: 15 minutes)
Topics:
Profit of quality at cost price
or
IT in entertainment industry.
(1)The price of a certain thing increases every odd
year by 25% And each even year it reduces
by 20%.....so what will happpen to a money after 10
years...... (3 marks)
ans: no loss no profit.
(2) This question is from shankuntala devi (only
sentences has changed)
Two trains are coming from opposite
direction at the speed of 30 miles per hour. and
initially the disence between this two train was 90
miles one pezion which is sitting on the one trainn ..
it is flying to another train ,and as soon as it has
reaches to another one it comes back to previous
train. and this is continyue till the collasion of the
train and flying speed of pezion is 18 miles per hour.
question is that how much distance pezion has
travelled.
Ans. 54 miles
2/two bikemen start at the same time from two
different destination towards each other on a sraight
lin path the distance between them is 36 km.. speed of
each bike is 6 km/hr......one bird starts flying from
one bike simultaneously......how much distance the
bird will travel when the two bikes meet.the speed of
the bird is 18 km/hr
3/ trains from amritsar to mumbai starts at 9:00 am
everyday........and reach mumbai at 9:30 am
after 3 days journey.....the similar is with the down
train.....it also start at 9:00 from mumbai and reach
amritsar at 9:300 after 3 days... the qs is one train
which is starting from amritsar will meet to how much
trains before reaching mumbai.....
Ans. 7 times
4/ there is a rope of 20 meter lenghth .....it is cut
into two pieces ....the two pieces are used to make
two squares using the ropes as perimeters....the qs is
what is the probablity that the area of one of the
square is greater than 9 m square/ what is
probabilty that the sum of the area of two squares is
greater than 20.5
Ans 0.8 or 0.2 (plz check it)
5/ ram's friend live in a house in the locality where
the house number starts from 1 to 82 when he asked his
house number he didnt says directly ........when ram
asked;;;
is it greater than 41?
is it divisible by 4?
is it a perfect square?
he answered all these answers...and ram got
the number.....is it possible ...if
possible then work out this.
Ans. 64
6/there was a question from baron i think.....and it
was not so difficult....a critical
reasoning type qs.......it was very big.....but easy
this is the question on age and answer is smeeta=
30, renu = 28, jyoti = 25
7/the difficult one i think no one have attempted
it......from summers i think.....
for interview they asked
tell about urself....
why do u want to go into software though u r
mechanical student........
why did u join M tech
and they asked 4 puzzles...
where do u find urself after 5 yrs..
the interview held for 30minutes....
. a. In a given RC circuit find the voltage across C
and R?
b. In a given CR circuit find the voltage across R and
C ?;
2.for the given _expression Y=A’B’C+A’BC+AB’C+ABC+ABC’
realize the following
a. 2 input and 3input NAND gate
b. 2 input and 3 input NOR gate
c. AND,OR, INVERTER.
d. INVERTER;
3.what is the importance of scan in digital system.;
4.given A XOR B =C, such that prove the following
a. B XOR C =A
b. A XOR BXOR C=0;
5. construct an input test pattern that can detect the
result E stuck at 1 in the ckt below
NAND (A,B)->E, NAND(C,D)->F
AND(E,F)->A.
6. in a given opamp ckt input offcet is 5mv,volatage
gain =10,000,vsat=+-15v
such that find the output voltage .
7. draw the p side equation of the circuit.(I am not
sulre about it)
8.make a JK FF using a D FF and 4->1 MUX.
9.use 2->1 MUX to implement the following _expression
Y=A+BC’+BC(A+B).
10.for the following ckt what is the relation between
fin and fout.?
the D FF use +ve edge triggered and have a intial
value is 0
CLK->two DFFs with complementing (i.e one DFF have CLK
and other one have
Complement of it),inputs of DFF is same and output of
DFFs is given to NOR
Gate and output of NOR gate is feedback to the two
DFFs.
11. design a asyncronous circuit for the following clk
waveforms.
CLK->thrice the CLK period->half the period of input.
12. what is the setup time and hold time parameters of
the FF, what happens if we are not consider it in
designing the digital ckt.
13. given two DFF A,B ones output is the input of
other and have the common clock.
Fmax if A and B are +ve edge triggered, if A is+ve
edge triggered ,B is -ve edge triggered what is the
Fmax relation to previous Fmax relation…
14. what are the FIFOS .? give some use of FIFOS in
design.
15. i don’t know about it but it is related to PCB
layout..
technical questions are completed.
remaining 10 questions are from optitude.
don’t worry about it.
these can be solve easily…
ALL THE BEST
20% fall. then after
10 years what will be there ,a rise or a fall
ans:no rise or fall 3
marks
2. there is a road with length 36 miles.from the one
end, one girl and
from the other a boy starts on a bike towards each
other , with the speed
of 6 miles per hour.when the girls starts one pegion
starts with her at
18 miles per hr speed, meets the boy and then comes
back to the girl.
calculate the total distance travelled by the
pegion.(it doesn't take any
rest.) 3
marks
ans:54 miles
3.a rope of 20 m is cut randomly in 2 pieces such that
they are the
perimeters of the sruare.
1]what is the probability that the area of the bigger
square is 9 m2 or
greater than that.
2]what is the proabibilty that the adddtion of the
areas is 20.5 m2 or
gereater than that.
4marks
4.between A and B stations S (NAME) train travels.it
stars at 9 am then
it reaches b after 3 days 9.30 am. now if such S train
starts from B to A
then , how many S trains does it meet till it
reaches station B ?
ans:7 4 marks.
5.H,W and L (names starting with these letters)are
taking part in one
quiz where 30 questions are asked.there were 45
correcxt answers, amongst
them W answers 55 % that of H.the correct answers
given by the W & L
are 1.25 times that given by H. then the correct
answers given by each
are?(the name of the anchor was also starting with the
letter H and hence
added confusion). 6 marks
ans:20,11,14
6.some lenthy proablem....... with statemnts revealing
the conditions.
green red
and ... houses. 5 neighbours , with different
nationality, different pets
and.....
statements. 6 mark
7.there are 1-82 houses in one colony. i wish to find
out the house no. of
my friend who has newly shifted there. i asked him 3
questions. the answer
may be yes/no. u can find the correct house no.
1]is the noumber above 41?
2]is it divisible by 4?
3]is it perfect square?
ans:64 6 marks
8. three girls r there . to find ut their ages i asked
the questions. one
of them always lies, and other 2 speak truth.
some statements........
then what r the ages. 8 mark.
ans:mostly 26 23 22
9. 3 tribes........... condiion for marriages......
8 mark
this is the Infosys paper at REC TRICHY. 96 were
>shortlisted.
>
results have to come.......
in all 9 questions:
>(1hour ) 50 marks
>Some Question are incomplete soory for that.as By
>the
>time i wrote them down ,i forgot some of them.
>
>Questions
1> there are 111 players participating in atennis
match.Each match uses a new ball.
The loser of each match is eliminated from the
competiton.Find the number of balls used inthe
tennis
compettion.
>ans: 110
>
2) a spider makes a web over a 10 square inch window
> frame. each day it make sthe web twice it has made
>the
>previous day.
>the spider completes the web in 30 days. calculate
>the
>amount of time taken if two spiders are spiining the
>web over the same window.
>(Assuming that each spider completes the work in an
>indepedent manner)
>ans: 29 days
3)Timothy has a stock of ties.consisting of 17 blue
>ties,11 yelow ties.34 orange,9violet and 2 black
>ties.
>the room in which the ties are kept is dark.find
>outhe
>minimum number of ties with timothy should take out
>of
>the room
>so that he has atleast two ties of the same color.
>Ans: 6
>
>4)in a company of 24900 employee,45% of the
>employess
>read Daily.
>60% read Courier,and 40% read Inquirer.
>15% read both Daily and courier
>25% read both Daily and Inquirer
>35% read both inquirer and courir
>while 10% read all the three.
>a) find out how many read daily only?
>b) find out howmany read inquirer only ,courir only
>c) how many dont read newspaper at all
note: it's easy to do in %form , write the answer in
percent
>5)at sabina park ,in a match between india and
>westindies
>the three indian bowlers showed a marvelles
>performance.
>bedi ,prassna and vekatraghvan. find out from the
>condition how many wickets did each score
>conditon 1:
>either bedi took allthe five wicket or prassana took
>3
>wickets
>conditon 2:
>either there was a runout or prassna took one more
>wicket than bedi
>conditon 3)
>the sum of bedi and twice that of prassana is one
>more
>than thrice venkatraghvan
>
> ans :
bedi- 2 wickets
prasana- 4 wickets
venkata - 3 wickets
1 runout
>6) there were two friends.kamal and sikandar both
>were
>talking to each other.
>kaml wanted to ask the age of sikandars 3 children.
>they had the following conversation
>sikandar: the product of their ages is 36
>kamal: i dont have caomplete info abouthis
>tell me something more
>sikandar:the sum of thier ages is equal to u r age.
>kaml: i still cant guess it
>sikandar:my son is more than one year old from both
>my
>daughters.
>
>find the age of the three children
>ans:9 2 2
>
>7)there was a burglary in a neighbourhood. Five
>elderly gentleman used to live in the neighbourhood.
>sherlock holme had come to investigate the
>burglary.he
>had the following facts derived from the
>conversation
> from the five men . Mr black,mr Green,Mr brown,Mr
>grey.
>Mr Plumb
>find their age and names of thier homes.
> conditions:
>A)the 56 and 58 dont live inthe oak house
>b) Mr green is older than mr black
>c) Mr
>
>8) identify the apperance of culprit in the robbery.
>acoording to the foloowuing conditon
>acoording to the guard ,the culprit had blue
>eyes,tall
>,wore a vest and hat
>acoording to the cashier ,the culprit had dark
>eyes,short,wore a vest and hat.
>acording to the secretary,the culprit had green
>eyes,was medium short,wore a raincaot and no hat
>acoording to the director ,the culprit had gray
>eys,was tall , didnot wear a vest but had a hat.
> After the detaild enquiry ,it was found that
>witnesses provided exactly one detail correctly.
>while the atleast one witness provided the correct
>detail oft he culprit.
>Give the appearance of the culprit.
ans : blue eyes,short, wore a raincoat without hat
>
>9) Questin on seating arrnagement from barrons
>there are 10 people:- 5 male L M,N,P,Q AND 5 FEMALE
>U,V,W,S,T
>ALL ARE MARRIED. THAT IS THERE ARE 5 COUPLES.
>they are invbited to a partyy where they are to be
>seated in a row having 10 seat.
>the men ae to occupy the odd numbered seats.while
>the
>women the even numbered seats.
>a) the man whom the woman are married to ,should sit
>at right side of her husband.
>b) Q is Vs husband
>c)
>d)
>
>
>five question based on the above 5-6 conditions.
>
>
ans : i'm not sure the last one..
a. d
b.e
c- c
d: ......
>after this there was an esay writin on :15mins
>"IT IN ENTERTAINMENT INDUSTRY"
>OR
>" COST OF QUALITY CONTROL
Infosys paper held on 4th august in N.I.T.Calicut.
1. There are three tins each one having two boxes.
One tin contains red balls in the two boxes. The
second tin contains blue balls in the two boxes.
The third one contains red balls in one box and blue
balls in another box. Three labels are prepared “red
–red”, ”blue-blue” and “red-blue”. The labels are
fixed randomly on the three boxes. What is the
probability that only one label showing wrong
information?
Ans: 0.
2. In one family there are some boys and some girls.
Each boy has as many brothers as his sisters. And
each girl has as many sisters as the half of her
brothers. How many boys and how many girls are there?
Ans; boys 4,girls 3;
3. In a birthday party there are total 11. Each one
shook his hand with another one only once. Then what
is the total number of shake hands?
Ans: 55.
4.One man is traveling with a constant speed. Due to
consumption of energy the distance traveled per hour
is decreasing same amount every hour. He traveled 135
miles in first two hours. And in the next two hours
he traveled 104 miles. What are the distances he
traveled in the first and the last (fourth) hours?
Ans: 571/8, 385/8
5.One problem with some description about a circus.
The answer is
Ans : BALU.
6. There are two types of tea powders. One costs
5Rs/Kg. And another one costs 3Rs/Kg. 40 Kg of the
mixture is sold at 6Rs/Kg. The profit is 100/3
percent. What are the amounts of tea powders
individually?
Ans: 30Kg,10Kg.
7. one problem with venndiagram about some people
listening to radio stations.
The answer is 400.
INFOSYS 2002 ANNA UNIVERSITY 1/8/2002
Analytical paper(Duration:60 min)
1. In a singles tennis tournament,111 players are
participating.
For each game they will use a new ball.If any player
looses his match,he will be rejected from the
game.then,how many balls are required for the entire
game in order to find out the winner.
(3 marks) 110
2.In a rack there are some ties of different colurs as
follows.
17 green, 11 yellow, 9 blue, 2 orange,7 red.
In dark,how many ties should we extract in order to
have two ties of same colour?
(4 marks)(6)
3.In a company there are 29060 employees.
60%read Daily news.
45% read Indian express.
40% read times of india.
25% read both hindu& indian express.
30% read both indian express and times of india.
10%read both hindu and times of india.
5%read all the paers.
then find
a. How many read only hindu?
b.How many read only indian express and times of
india?
c.How many do not read news paers at all?
(4 marks)
4.one spider is spinning an area of window.It takes 30
days to complete the entire frame provided the
condition is it will spin the same area in the next
day as that of the previous day.
If 2 spiders do this work,then how many days will
those take provided the area spinned by one spider is
equal to that of the other.
(29 days)(4 marks)
5.There are 5 persons lying in one cottage area.
mr.brown, Mr.green, Mr.grey, Mr. plumb, Mr.blue
There are some clues were given about their living
areas and ages.
At last we have to find out their respective ages and
living areas.(GRE analytical type)
(8 marks)
6.Mr.Tom has 3 children.The conversation between him
and his friend George was going like this.
Tom: product of their ages is 36.
The son is elder than each of his sisters by more than
one year.
Can u find their ages?
(4,3,3)(4 marks)
7.The seating arrangement in a theatre is given by
means of some clues.
There are 5 men(l,m,n,p,q) and 5 women(s,t,u,v,w).
Conditions:
1. men will sit in the odd numbered seats.
2......(GRE analytical type)
(8 marks)
8.There was a cricket match and the description of the
no. of wickets taken by 3 plaers b,v,p are as follows.
Either B takes 5 wickets and v takes 3 or p takes a
wicket more than v.
Either B takes half of total wickets or One player is
run out.
Using these, find out the no.of wickets taken by each
player.
(6 marks) ans:4,3,2
9.Gre type like if 2 of 4 say lies then find the
correct one provided the clues given by each of them.
(8 marks) ans:Guard
The other paper is on english comprehension.
(Time: 15 minutes)
Topics:
Profit of quality at cost price
or
IT in entertainment industry.
(1)The price of a certain thing increases every odd
year by 25% And each even year it reduces
by 20%.....so what will happpen to a money after 10
years...... (3 marks)
ans: no loss no profit.
(2) This question is from shankuntala devi (only
sentences has changed)
Two trains are coming from opposite
direction at the speed of 30 miles per hour. and
initially the disence between this two train was 90
miles one pezion which is sitting on the one trainn ..
it is flying to another train ,and as soon as it has
reaches to another one it comes back to previous
train. and this is continyue till the collasion of the
train and flying speed of pezion is 18 miles per hour.
question is that how much distance pezion has
travelled.
Ans. 54 miles
2/two bikemen start at the same time from two
different destination towards each other on a sraight
lin path the distance between them is 36 km.. speed of
each bike is 6 km/hr......one bird starts flying from
one bike simultaneously......how much distance the
bird will travel when the two bikes meet.the speed of
the bird is 18 km/hr
3/ trains from amritsar to mumbai starts at 9:00 am
everyday........and reach mumbai at 9:30 am
after 3 days journey.....the similar is with the down
train.....it also start at 9:00 from mumbai and reach
amritsar at 9:300 after 3 days... the qs is one train
which is starting from amritsar will meet to how much
trains before reaching mumbai.....
Ans. 7 times
4/ there is a rope of 20 meter lenghth .....it is cut
into two pieces ....the two pieces are used to make
two squares using the ropes as perimeters....the qs is
what is the probablity that the area of one of the
square is greater than 9 m square/ what is
probabilty that the sum of the area of two squares is
greater than 20.5
Ans 0.8 or 0.2 (plz check it)
5/ ram's friend live in a house in the locality where
the house number starts from 1 to 82 when he asked his
house number he didnt says directly ........when ram
asked;;;
is it greater than 41?
is it divisible by 4?
is it a perfect square?
he answered all these answers...and ram got
the number.....is it possible ...if
possible then work out this.
Ans. 64
6/there was a question from baron i think.....and it
was not so difficult....a critical
reasoning type qs.......it was very big.....but easy
this is the question on age and answer is smeeta=
30, renu = 28, jyoti = 25
7/the difficult one i think no one have attempted
it......from summers i think.....
for interview they asked
tell about urself....
why do u want to go into software though u r
mechanical student........
why did u join M tech
and they asked 4 puzzles...
where do u find urself after 5 yrs..
the interview held for 30minutes....
. a. In a given RC circuit find the voltage across C
and R?
b. In a given CR circuit find the voltage across R and
C ?;
2.for the given _expression Y=A’B’C+A’BC+AB’C+ABC+ABC’
realize the following
a. 2 input and 3input NAND gate
b. 2 input and 3 input NOR gate
c. AND,OR, INVERTER.
d. INVERTER;
3.what is the importance of scan in digital system.;
4.given A XOR B =C, such that prove the following
a. B XOR C =A
b. A XOR BXOR C=0;
5. construct an input test pattern that can detect the
result E stuck at 1 in the ckt below
NAND (A,B)->E, NAND(C,D)->F
AND(E,F)->A.
6. in a given opamp ckt input offcet is 5mv,volatage
gain =10,000,vsat=+-15v
such that find the output voltage .
7. draw the p side equation of the circuit.(I am not
sulre about it)
8.make a JK FF using a D FF and 4->1 MUX.
9.use 2->1 MUX to implement the following _expression
Y=A+BC’+BC(A+B).
10.for the following ckt what is the relation between
fin and fout.?
the D FF use +ve edge triggered and have a intial
value is 0
CLK->two DFFs with complementing (i.e one DFF have CLK
and other one have
Complement of it),inputs of DFF is same and output of
DFFs is given to NOR
Gate and output of NOR gate is feedback to the two
DFFs.
11. design a asyncronous circuit for the following clk
waveforms.
CLK->thrice the CLK period->half the period of input.
12. what is the setup time and hold time parameters of
the FF, what happens if we are not consider it in
designing the digital ckt.
13. given two DFF A,B ones output is the input of
other and have the common clock.
Fmax if A and B are +ve edge triggered, if A is+ve
edge triggered ,B is -ve edge triggered what is the
Fmax relation to previous Fmax relation…
14. what are the FIFOS .? give some use of FIFOS in
design.
15. i don’t know about it but it is related to PCB
layout..
technical questions are completed.
remaining 10 questions are from optitude.
don’t worry about it.
these can be solve easily…
ALL THE BEST
EE 1401 ECONOMIC DISPATCH CONTROL
1. What is the purpose of economic dispatch?
The purpose of economic dispatch (or) optimal dispatch is to minimize the fuel costs for the power system.
2. What is meant by unit commitment?
Unit commitment means optimum allocation of generators at each generating station at various station load levels.
3. Name the methods of finding economic dispatch.
The two methods to find economic dispatch are:
(i) Load scheduling
(ii) Unit commitment
4. What is meant by total generator operating cost?
The total generator operating cost includes the cost of fuel, cost of transmission loss, labor and maintenance costs.
5. What are the factors affecting the cost of generation? (or) List the various constraints in the modern power systems.
The cost of generation depends on operating constraints or system constraints. They are:
• Equality constraint.
• Inequality constraint
o Generator constraints
o Voltage constraints
o Running space capacity constraints.
o Transformers tap settings.
o Transmission line constraints.
6. When do discontinuities occur in the fuel cost curve and the incremental cost curve?
The discontinuities occur when the output power has to be extended by using additional boilers, steam condensers, etc. The discontinuities also appear if the cost represents the operation of an entire power station.
7. What are the advantages of using participation factor?
The advantages of using participation factor are:
(a) Computer implementation of economic dispatch is straight forward.
(b) Execution time for economic dispatch is short.
(c) It will always give consistent answers when units reach limits.
(d) It gives linear incremental cost functions or has non-convex cost curves.
8. What is the difference between load frequency controller and economic dispatch controller?
The load frequency controller is a fast acting controller and the economic dispatch controller is a slow acting control. LFC adjusts the speed changer setting every minute in accordance with a command signal generated by the central economic dispatch computer.
9. What is merit order scheduling?
This method ensures that the incremental cost of all the generators is constant over the full range (or) over successive discrete portions within the range. This method of scheduling is known as merit order scheduling.
10. What is Lagrangian multiplier?
The necessary condition for the existence of a minimum cost operating condition is that the incremental cost rates of all the units be equal to some undetermined value(λ) called Lagrangian multiplier.
11. What is all the point to be noted for a economic load dispatch including transmission losses?
1) The incremental cost of production of a plant is always positive; the incremental transmission losses can be both positive and negative.
2) The individual generators will operate at different incremental cost of production.
3) The generation with highest positive incremental transmission loss will operate at lowest incremental cost of production.
12. What are the assumptions for deriving loss coefficients?
1. The ratio X/R for all transmission line is same.
2. The phase angle of all the load currents is the same.
13. How is incremental operating cost related to economic dispatch?
Total system load has to be divided among all units that all the units operate at equal incremental cost.
14. What are the criteria that should be satisfied for economic loading of generating station?
Equal incremental cost criteria.
15. Write the relationship between fuel energy input and input fuel cost.
Input fuel cost Fi (Pi)=K.Fi(Pi) Rs/hr
Where, K = Cost of the fuel in Rs/MKcal.
Fi (Pi) = Fuel energy input in MKcal/hr.
16. Write the quadratic expression of fuel cost.
Fi (Pi)= = αi (Pi) + βi (Pi) + γi Rs/hr
Where αi, βi, γi are constants.
(Pi)=Power generation
17. What is system incremental cost?
The incremental fuel cost of all the generating units must be the same. The common value of incremental fuel cost λ is called the system incremental cost.
18. Define incremental efficiency?
It is defined as the reciprocal of incremental fuel rate or incremental production cost.
26. How can the economic controller be added as the tertiary loop of LFC control?
The economic dispatch control equipment comprises of a function generator to find desired generation from λ, comparator to detect the error by comparing the desired gen eration with actual MW generation, low gain integral controller provided at energy control centre to send the correcting signal for readjustment of speed changer position. This low gain of the integral controller ensures slower action of the secondary control. Thus economic controller can be added to LFC loop
27. Compare with unit commitment and economic load dispatch.
Unit Commitment Economic Load dispatch
Optimum allocation of number of units to be operated (to determine this units of a plant that should operate for a given load is the problem of unit commitment Optimum allocation of generation to each system. (St each generating station at various station load levels)
There are number of subsets of the complete set of ’n’ units that would satisfy the expected demand. The problem assumes that there are ‘n; units already connected to the system.
Purpose of unit commitment is to find the optimal subset among the subsets which provide the minimum operating cost. Purpose of economic dispatch problem is to find the optimum operating policy for these ‘n’ units
The purpose of economic dispatch (or) optimal dispatch is to minimize the fuel costs for the power system.
2. What is meant by unit commitment?
Unit commitment means optimum allocation of generators at each generating station at various station load levels.
3. Name the methods of finding economic dispatch.
The two methods to find economic dispatch are:
(i) Load scheduling
(ii) Unit commitment
4. What is meant by total generator operating cost?
The total generator operating cost includes the cost of fuel, cost of transmission loss, labor and maintenance costs.
5. What are the factors affecting the cost of generation? (or) List the various constraints in the modern power systems.
The cost of generation depends on operating constraints or system constraints. They are:
• Equality constraint.
• Inequality constraint
o Generator constraints
o Voltage constraints
o Running space capacity constraints.
o Transformers tap settings.
o Transmission line constraints.
6. When do discontinuities occur in the fuel cost curve and the incremental cost curve?
The discontinuities occur when the output power has to be extended by using additional boilers, steam condensers, etc. The discontinuities also appear if the cost represents the operation of an entire power station.
7. What are the advantages of using participation factor?
The advantages of using participation factor are:
(a) Computer implementation of economic dispatch is straight forward.
(b) Execution time for economic dispatch is short.
(c) It will always give consistent answers when units reach limits.
(d) It gives linear incremental cost functions or has non-convex cost curves.
8. What is the difference between load frequency controller and economic dispatch controller?
The load frequency controller is a fast acting controller and the economic dispatch controller is a slow acting control. LFC adjusts the speed changer setting every minute in accordance with a command signal generated by the central economic dispatch computer.
9. What is merit order scheduling?
This method ensures that the incremental cost of all the generators is constant over the full range (or) over successive discrete portions within the range. This method of scheduling is known as merit order scheduling.
10. What is Lagrangian multiplier?
The necessary condition for the existence of a minimum cost operating condition is that the incremental cost rates of all the units be equal to some undetermined value(λ) called Lagrangian multiplier.
11. What is all the point to be noted for a economic load dispatch including transmission losses?
1) The incremental cost of production of a plant is always positive; the incremental transmission losses can be both positive and negative.
2) The individual generators will operate at different incremental cost of production.
3) The generation with highest positive incremental transmission loss will operate at lowest incremental cost of production.
12. What are the assumptions for deriving loss coefficients?
1. The ratio X/R for all transmission line is same.
2. The phase angle of all the load currents is the same.
13. How is incremental operating cost related to economic dispatch?
Total system load has to be divided among all units that all the units operate at equal incremental cost.
14. What are the criteria that should be satisfied for economic loading of generating station?
Equal incremental cost criteria.
15. Write the relationship between fuel energy input and input fuel cost.
Input fuel cost Fi (Pi)=K.Fi(Pi) Rs/hr
Where, K = Cost of the fuel in Rs/MKcal.
Fi (Pi) = Fuel energy input in MKcal/hr.
16. Write the quadratic expression of fuel cost.
Fi (Pi)= = αi (Pi) + βi (Pi) + γi Rs/hr
Where αi, βi, γi are constants.
(Pi)=Power generation
17. What is system incremental cost?
The incremental fuel cost of all the generating units must be the same. The common value of incremental fuel cost λ is called the system incremental cost.
18. Define incremental efficiency?
It is defined as the reciprocal of incremental fuel rate or incremental production cost.
26. How can the economic controller be added as the tertiary loop of LFC control?
The economic dispatch control equipment comprises of a function generator to find desired generation from λ, comparator to detect the error by comparing the desired gen eration with actual MW generation, low gain integral controller provided at energy control centre to send the correcting signal for readjustment of speed changer position. This low gain of the integral controller ensures slower action of the secondary control. Thus economic controller can be added to LFC loop
27. Compare with unit commitment and economic load dispatch.
Unit Commitment Economic Load dispatch
Optimum allocation of number of units to be operated (to determine this units of a plant that should operate for a given load is the problem of unit commitment Optimum allocation of generation to each system. (St each generating station at various station load levels)
There are number of subsets of the complete set of ’n’ units that would satisfy the expected demand. The problem assumes that there are ‘n; units already connected to the system.
Purpose of unit commitment is to find the optimal subset among the subsets which provide the minimum operating cost. Purpose of economic dispatch problem is to find the optimum operating policy for these ‘n’ units
EE 1401 POWER SYSTEM OPERATION AND CONROL(2 marks)
UNIT- IV UNIT COMMITMENT – ECONOMIC DISPATCH CONTROL
1. What is the need for unit commitment?
Need for unit commitments are:
Enough units will be committed to supply the system load.
To reduce the loss or fuel cost.
By running the most economic unit, the load can be supplied by that unit operating closer to its best efficiency.
2. What a re the difficulties to find unit commitment solution?
Time consuming process
If the number of units is more, the number of combinations is more in a complex bus system.
If ‘n’ be the number of units, then the number of combinations will be (2n - 1)
3. List he constraints that are accounted in unit commitment problem.
• Spinning reserve
• Thermal Constraints
o Minimum downtime
o Minimum uptime
o Crew constraint
• Other constraints
o Hydro constraint
o Must run constraint
o Fuel constraint
4. What is the constraint for blue force technique? Is it possible to get an optimum solution with this technique and explain how?
i. Spinning reserve
ii. Thermal Constraints
1. Minimum downtime
2. Minimum uptime
3. Crew constraint
iii. Other constraints
1. Hydro constraint
2. Must run constraint
3. Fuel constraint
5. What is meant by priority list method?
Priority list method is the simplest unit commitment solution method which consists of creating a priority list of units. The priority list can be obtained by noting the full-load average production cost of each unit.
6. What are the assumptions for priority list method using full load average production cost?
• No load costs are zero.
• Unit input-output characteristics are linear between zero output and full load.
• Start-up costs are a fixed amount.
• Ignore minimum up time and minimum down time.
7. What are the merits and demerits of priority list method?
Merits:
No need to go for ‘N’ combinations
Take only one constraint.
Ignore minimum up time and minimum down time.
Complication reduced.
Demerits:
Start-up costs are fixed amount.
No load costs are not considered.
8. What are the advantages of using forward dynamic programming method?
Reduction in the dimensionality of the problem. i.e., number of combinations to be tried is reduced in number.
If a strict priority is imposed, the number of combinations for a 4 unit case are:
Priority 1 unit
Priority 1 unit + Priority 2 unit
Priority 1 unit + Priority 2 unit + Priority 3 unit
Priority 1 unit + Priority 2 unit + Priority 3 unit + Priority 4 unit
9. What are the assumptions involved in dynamic programming method?
• Total number of units available, their individual cost characteristic and the load cycle on the station are assumed priori (previously).
• A state consists of an array of units with specified units operating and the rest off-line.
• The Start-up cost of a unit is independent of the time it has been off-line (i.e., fixed amount)
• There are no costs for shutting down a unit.
• There is a strict priority order and in each interval a specified minimum amount of capacity must be operating
1. What is the need for unit commitment?
Need for unit commitments are:
Enough units will be committed to supply the system load.
To reduce the loss or fuel cost.
By running the most economic unit, the load can be supplied by that unit operating closer to its best efficiency.
2. What a re the difficulties to find unit commitment solution?
Time consuming process
If the number of units is more, the number of combinations is more in a complex bus system.
If ‘n’ be the number of units, then the number of combinations will be (2n - 1)
3. List he constraints that are accounted in unit commitment problem.
• Spinning reserve
• Thermal Constraints
o Minimum downtime
o Minimum uptime
o Crew constraint
• Other constraints
o Hydro constraint
o Must run constraint
o Fuel constraint
4. What is the constraint for blue force technique? Is it possible to get an optimum solution with this technique and explain how?
i. Spinning reserve
ii. Thermal Constraints
1. Minimum downtime
2. Minimum uptime
3. Crew constraint
iii. Other constraints
1. Hydro constraint
2. Must run constraint
3. Fuel constraint
5. What is meant by priority list method?
Priority list method is the simplest unit commitment solution method which consists of creating a priority list of units. The priority list can be obtained by noting the full-load average production cost of each unit.
6. What are the assumptions for priority list method using full load average production cost?
• No load costs are zero.
• Unit input-output characteristics are linear between zero output and full load.
• Start-up costs are a fixed amount.
• Ignore minimum up time and minimum down time.
7. What are the merits and demerits of priority list method?
Merits:
No need to go for ‘N’ combinations
Take only one constraint.
Ignore minimum up time and minimum down time.
Complication reduced.
Demerits:
Start-up costs are fixed amount.
No load costs are not considered.
8. What are the advantages of using forward dynamic programming method?
Reduction in the dimensionality of the problem. i.e., number of combinations to be tried is reduced in number.
If a strict priority is imposed, the number of combinations for a 4 unit case are:
Priority 1 unit
Priority 1 unit + Priority 2 unit
Priority 1 unit + Priority 2 unit + Priority 3 unit
Priority 1 unit + Priority 2 unit + Priority 3 unit + Priority 4 unit
9. What are the assumptions involved in dynamic programming method?
• Total number of units available, their individual cost characteristic and the load cycle on the station are assumed priori (previously).
• A state consists of an array of units with specified units operating and the rest off-line.
• The Start-up cost of a unit is independent of the time it has been off-line (i.e., fixed amount)
• There are no costs for shutting down a unit.
• There is a strict priority order and in each interval a specified minimum amount of capacity must be operating
EE 1401 POWER SYSTEM OPERATION AND CONTROL(2 marks)
UNIT- III RECATIVE POWER AND VOLTAGE CONTROL
1. What is the relationship between voltage and reactive power?
Q1, Q2 –Sending end and receiving reactive power respectively
V1, V2- Sending end and receiving Voltages respectively
X –Total transfer reactance between sending end and receiving end side.
2. What are the Methods of Voltage Control?
i. Excitation control with AVR in generating stations
ii. Tap changing transformers using in sending and receiving end of the transmission line.
iii. Shunt reactors – Low loads
iv. Shunt capacitors – high loads or low p.f load
v. Series capacitors –long EHV transmission line
vi. Synchronous condenser or compensator
vii. Static VAR compensator (SVC)
3. What is exciter?
The fields winding of synchronous machines (alternator) are always supplied with d.c from d.c generators called exciter.
4. What are the various functions of excitation system?
Exciter is the main component in the AVR loop .It delivers the d.c power to the generator field. It must have adequate power capacity and sufficient speed response.
5. What are the types of excitation system?
1. D.C Excitation system
2. A.C Excitation system
3. Static Excitation system.
6. What are effects of AVR loop?
1. AVR must regulate the terminal voltage V within required static accuracy limit
2. It must have sufficient speed response
3. It must be stable.
7. What is the necessity of stability compensation in AVR loop?
Stability compensation improves the dynamic response characteristics without affecting the static loop gain.
8. What are the power system components are generate and absorb the reactive power?
Synchronous machine under over excited condition, Shunt capacitor and cable are generating reactive power.
Shunt reactor, overhead lines, transformer and Load are absorbing the reactive power.
9. Compare shunt and series capacitors.
S.No Shunt capacitors Series capacitors
1 Shunt capacitors supply capacitive reactive power to the system at the point where they are connected. Series capacitors are connected in series with the line and are used to reduce inductive reactance between supply point and load
2 It is mainly used for power factor correction at the load terminal of low voltage It is mainly used to compensate the effect of series reactance.
3 If the loadVAR requirement is small, shunt capacitors are of high use. If the load VAR requirement is small, series capacitors are of small use
4 If the total line reactance is high, shunt capacitors are not effective. If the total reactance is high series capacitors are very effective and stability is improved
10. What is a synchronous compensator?
A Synchronous condenser is a synchronous machine running without a prime mover or a mechanical load under over excited condition. It has wide variation excitation control. It can be made to either generate or absorb reactive power.
11. Where synchronous condensers installed?
The synchronous compensator is connected to the tertiary winding of the main transformer for voltage and reactive power control at both transmission and sub transmission level. A neutral point is provided by the earthling transformer.
12. What are the advantages and disadvantages of synchronous compensator?
Advantages:
1. Flexibility of operation for all conditions
2. As the losses are considerable compared with static capacitors and the power factor is not zero.
Disadvantages:
1. The cost of installation is high
2. Losses of synchronous condensers are much high compared to those of capacitors.
13. How is voltage control obtained by using tap changing transformers?
Voltage is controlled with the help of line drop compensator, voltage sensitive regulating relay, time delay relay, etc
By changing the turns ratio of transformer the voltage ratio and the secondary voltage is changed and the voltage control is obtained. So, voltage control of transmission and distribution system is obtained by tap changing.
14. What is Static VAR Compensator (SVC)? Where it is used?
SVCs are Shunt connected static generators and/or absorber whose outputs are varied so as to control specific parameters of the electric power system.
The term static is used to indicate the SVC, have no moving, or rotating main components. Thus an SVC consists of static VAR generator or absorber devices and suitable devices.
SVC s are located in receiving substations and distribution systems for smooth and steeples variation of compensation of reactive power injected into the line, by shunt capacitors and shunt reactors.
15. What are the different types of SVC?
The following are the basic types of reactive power control elements which make up all or part of any static VAR system.
i. Saturated reactor(SR)
ii. Thyristor controlled reactor(TCR)
iii. Thyristor controlled Transformer(TCT)
iv. Thyristor Switched Reactor(TSR)
v. Thyristor Switched capacitor(TSC)
vi. Self or line commutated converter(SCC/LCC)
16. Write the some applications of SVC.
i. Control of temporary (power frequency) over voltages
ii. Prevention of voltage collapse
iii. Enhancement of transient stability
iv. Enhancement of damping of system oscillations
1. What is the relationship between voltage and reactive power?
Q1, Q2 –Sending end and receiving reactive power respectively
V1, V2- Sending end and receiving Voltages respectively
X –Total transfer reactance between sending end and receiving end side.
2. What are the Methods of Voltage Control?
i. Excitation control with AVR in generating stations
ii. Tap changing transformers using in sending and receiving end of the transmission line.
iii. Shunt reactors – Low loads
iv. Shunt capacitors – high loads or low p.f load
v. Series capacitors –long EHV transmission line
vi. Synchronous condenser or compensator
vii. Static VAR compensator (SVC)
3. What is exciter?
The fields winding of synchronous machines (alternator) are always supplied with d.c from d.c generators called exciter.
4. What are the various functions of excitation system?
Exciter is the main component in the AVR loop .It delivers the d.c power to the generator field. It must have adequate power capacity and sufficient speed response.
5. What are the types of excitation system?
1. D.C Excitation system
2. A.C Excitation system
3. Static Excitation system.
6. What are effects of AVR loop?
1. AVR must regulate the terminal voltage V within required static accuracy limit
2. It must have sufficient speed response
3. It must be stable.
7. What is the necessity of stability compensation in AVR loop?
Stability compensation improves the dynamic response characteristics without affecting the static loop gain.
8. What are the power system components are generate and absorb the reactive power?
Synchronous machine under over excited condition, Shunt capacitor and cable are generating reactive power.
Shunt reactor, overhead lines, transformer and Load are absorbing the reactive power.
9. Compare shunt and series capacitors.
S.No Shunt capacitors Series capacitors
1 Shunt capacitors supply capacitive reactive power to the system at the point where they are connected. Series capacitors are connected in series with the line and are used to reduce inductive reactance between supply point and load
2 It is mainly used for power factor correction at the load terminal of low voltage It is mainly used to compensate the effect of series reactance.
3 If the loadVAR requirement is small, shunt capacitors are of high use. If the load VAR requirement is small, series capacitors are of small use
4 If the total line reactance is high, shunt capacitors are not effective. If the total reactance is high series capacitors are very effective and stability is improved
10. What is a synchronous compensator?
A Synchronous condenser is a synchronous machine running without a prime mover or a mechanical load under over excited condition. It has wide variation excitation control. It can be made to either generate or absorb reactive power.
11. Where synchronous condensers installed?
The synchronous compensator is connected to the tertiary winding of the main transformer for voltage and reactive power control at both transmission and sub transmission level. A neutral point is provided by the earthling transformer.
12. What are the advantages and disadvantages of synchronous compensator?
Advantages:
1. Flexibility of operation for all conditions
2. As the losses are considerable compared with static capacitors and the power factor is not zero.
Disadvantages:
1. The cost of installation is high
2. Losses of synchronous condensers are much high compared to those of capacitors.
13. How is voltage control obtained by using tap changing transformers?
Voltage is controlled with the help of line drop compensator, voltage sensitive regulating relay, time delay relay, etc
By changing the turns ratio of transformer the voltage ratio and the secondary voltage is changed and the voltage control is obtained. So, voltage control of transmission and distribution system is obtained by tap changing.
14. What is Static VAR Compensator (SVC)? Where it is used?
SVCs are Shunt connected static generators and/or absorber whose outputs are varied so as to control specific parameters of the electric power system.
The term static is used to indicate the SVC, have no moving, or rotating main components. Thus an SVC consists of static VAR generator or absorber devices and suitable devices.
SVC s are located in receiving substations and distribution systems for smooth and steeples variation of compensation of reactive power injected into the line, by shunt capacitors and shunt reactors.
15. What are the different types of SVC?
The following are the basic types of reactive power control elements which make up all or part of any static VAR system.
i. Saturated reactor(SR)
ii. Thyristor controlled reactor(TCR)
iii. Thyristor controlled Transformer(TCT)
iv. Thyristor Switched Reactor(TSR)
v. Thyristor Switched capacitor(TSC)
vi. Self or line commutated converter(SCC/LCC)
16. Write the some applications of SVC.
i. Control of temporary (power frequency) over voltages
ii. Prevention of voltage collapse
iii. Enhancement of transient stability
iv. Enhancement of damping of system oscillations
Friday, September 25, 2009
45V, 750mA LED Driver for Boost, Buck or Buck-Boost High Current LED Applications
MILPITAS, CA - September 16, 2009 - Linear Technology announces the LT3519, a 45V, high side current sense DC/DC converter designed to drive high current LEDs. The LT3519's 3V to 40V input voltage range makes it ideal for applications such as automotive and industrial lighting. The combination of an internal 45V, 750mA switch, Schottky diode and internal compensation provides a highly compact LED driver solution.The LT3519 can drive up to ten 100mA white LEDs from a 12V input, making it ideal for a variety of applications such as automotive and industrial lighting. It can deliver efficiencies up to 90% in boost mode from a compact MSOP-16E package. The LT3519 utilizes True Color PWM™ dimming to deliver constant LED color with ranges of more than 3,000:1. For less demanding dimming requirements, the CTRL pin can be used to offer 10:1 analog dimming. The device's fixed frequency, constant current, constant voltage regulation provides stable operation over a wide range of supply and output voltages, while ensuring uniform brightness of LEDs. There are three switching frequency options available: the LT3519, which switches at 400kHz; the LT3519-1, which switches at 1MHz; and theLT3519-2, offering a 2.2MHz switching frequency, enabling designers to optimize efficiency while minimizing external component size.The LT3519 senses output current at the high side of the LED, enabling buck, buck-boost or boost configurations. Combining a traditional voltage feedback and unique floating current sense feedback, these converters can operate as constant voltage or constant current source, offering maximum design flexibility. Other features include open LED protection, soft-start and thermal protection.
The LT3519EMS, LT3519EMS-1 and LT3519EMS-2 are available in an MSOP-16 package and are priced starting at $2.50 each, in 1,000-piece quantities. Extended temperature versions, or "I" grades, namely the LT3519IMS,LT3519IMS-1 and LT3519IMS-2, are tested and guaranteed to operate from a -40ºC to 125ºC operating junction temperature. They are priced at $2.94 each in 1,000-piece quantities. All versions are available from stock. For more information, visit www.linear.com.
Summary of Features: LT3519
Up to 3000:1 True Color PWM™ Dimming
3V to 40V Input Voltage Range
Floating LED Current Sense from 0V to 45V
45V, 750mA Internal Switch
Internal Schottky Diode
Constant Current & Constant Voltage Regulation
Boost, SEPIC, Buck-Boost Mode or Buck Mode Topology
Open LED Protection & Open LED Status Pin
Programmable Undervoltage Lockout with Hysteresis
Fixed Frequency: 400kHz (LT3519), 1MHz
(LT3519-1) or 2.2MHz (LT3519-2)
Internal Compensation
CTRL Pin Provides Analog Dimming
Low Shutdown Current: <1µA
16-Lead MSOP Package
About Linear Technology
Linear Technology Corporation, a manufacturer of high performance linear integrated circuits, was founded in 1981, became a public company in 1986 and joined the S&P 500 index of major public companies in 2000. Linear Technology products include high performance amplifiers, comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery chargers, data converters, communications interface circuits, RF signal conditioning circuits, µModule® products, and many other analog functions. Applications for Linear Technology's high performance circuits include telecommunications, cellular telephones, networking products such as optical switches, notebook and desktop computers, computer peripherals, video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer products such as digital cameras and MP3 players, complex medical devices, automotive electronics, factory automation, process control, and military and space systems.
The LT3519EMS, LT3519EMS-1 and LT3519EMS-2 are available in an MSOP-16 package and are priced starting at $2.50 each, in 1,000-piece quantities. Extended temperature versions, or "I" grades, namely the LT3519IMS,LT3519IMS-1 and LT3519IMS-2, are tested and guaranteed to operate from a -40ºC to 125ºC operating junction temperature. They are priced at $2.94 each in 1,000-piece quantities. All versions are available from stock. For more information, visit www.linear.com.
Summary of Features: LT3519
Up to 3000:1 True Color PWM™ Dimming
3V to 40V Input Voltage Range
Floating LED Current Sense from 0V to 45V
45V, 750mA Internal Switch
Internal Schottky Diode
Constant Current & Constant Voltage Regulation
Boost, SEPIC, Buck-Boost Mode or Buck Mode Topology
Open LED Protection & Open LED Status Pin
Programmable Undervoltage Lockout with Hysteresis
Fixed Frequency: 400kHz (LT3519), 1MHz
(LT3519-1) or 2.2MHz (LT3519-2)
Internal Compensation
CTRL Pin Provides Analog Dimming
Low Shutdown Current: <1µA
16-Lead MSOP Package
About Linear Technology
Linear Technology Corporation, a manufacturer of high performance linear integrated circuits, was founded in 1981, became a public company in 1986 and joined the S&P 500 index of major public companies in 2000. Linear Technology products include high performance amplifiers, comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery chargers, data converters, communications interface circuits, RF signal conditioning circuits, µModule® products, and many other analog functions. Applications for Linear Technology's high performance circuits include telecommunications, cellular telephones, networking products such as optical switches, notebook and desktop computers, computer peripherals, video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer products such as digital cameras and MP3 players, complex medical devices, automotive electronics, factory automation, process control, and military and space systems.
Earn through Google
What is Pay Per Click Internet Advertising?
When operating a website for profit, using pay per click advertising or PPC, is a must to get Internet traffic to the website. No traffic translates into no profits. Google PPC advertising is similar to other PPC advertising search engines like Yahoo and MSN, but Google is the giant. If a web master is going to use PPC advertising, Google has more programs than any other search engine to get Internet traffic to a website.
What is Pay Per Click Internet Advertising – Sponsored Listings?
PPC advertising are ads that are placed with a search engine company like Google. The website owner only pays for ads when they’re clicked by an Internet user. PPC ads are also known as sponsored ads. Once the Internet user clicks on a sponsored ad, the web owner is charged a click fee and the Internet users are linked and directed to the website or to a specific web page.
Pay per Click Ads – Sponsored Listings vs. Natural Listings
Natural searches are what the Internet search engine computers (a.k.a. spiders) pick up from websites and list for free. Sponsored searches are searches that are listed and the advertisers are charged a fee every time an Internet user clicks on the ad. The Internet search engine companies call them cost-per-click or CPC. The sponsored ads are generally listed on the top, on the side and on the bottom of the search page. They will also be listed with the words “sponsored links.”
Advantages of Sponsored Listings vs. Natural Listings
* With a sponsored listing there’s much more control over page ranking.
* With a sponsored listing there’s control over how the ads read, word for word. With a natural search it’s not known what words will be picked up by the spider and listed.
* Sponsored listings allow the ads to be directed to any page of the website that the web master chooses.
* Sponsored listings allow the web master to choose keywords of their choice and choose as many keywords as they desire.
* With a sponsored listing the keywords don’t have to be in the listed ad.
* Sponsored listings allows the web master to track lots of information that’s invaluable to the profitability of their business.
The biggest disadvantage, of course, is that sponsored listing costs money and in some cases can get expensive. The web master does however have complete control over how much they spend.
What’s the Cost for Pay Per Click Internet Advertising?
Since PPC advertising only charges when an Internet user clicks on the ad, the web master can choose how much they are willing to spend per click. The actual cost is based on the keywords used. As a general rule, the more popular the keyword phrase is to Internet searches, the more the cost per click (CPC). The web master bids against other web masters and the one with the higher bids gets better ad placement and page rankings.
When operating a website for profit, using pay per click advertising or PPC, is a must to get Internet traffic to the website. No traffic translates into no profits. Google PPC advertising is similar to other PPC advertising search engines like Yahoo and MSN, but Google is the giant. If a web master is going to use PPC advertising, Google has more programs than any other search engine to get Internet traffic to a website.
What is Pay Per Click Internet Advertising – Sponsored Listings?
PPC advertising are ads that are placed with a search engine company like Google. The website owner only pays for ads when they’re clicked by an Internet user. PPC ads are also known as sponsored ads. Once the Internet user clicks on a sponsored ad, the web owner is charged a click fee and the Internet users are linked and directed to the website or to a specific web page.
Pay per Click Ads – Sponsored Listings vs. Natural Listings
Natural searches are what the Internet search engine computers (a.k.a. spiders) pick up from websites and list for free. Sponsored searches are searches that are listed and the advertisers are charged a fee every time an Internet user clicks on the ad. The Internet search engine companies call them cost-per-click or CPC. The sponsored ads are generally listed on the top, on the side and on the bottom of the search page. They will also be listed with the words “sponsored links.”
Advantages of Sponsored Listings vs. Natural Listings
* With a sponsored listing there’s much more control over page ranking.
* With a sponsored listing there’s control over how the ads read, word for word. With a natural search it’s not known what words will be picked up by the spider and listed.
* Sponsored listings allow the ads to be directed to any page of the website that the web master chooses.
* Sponsored listings allow the web master to choose keywords of their choice and choose as many keywords as they desire.
* With a sponsored listing the keywords don’t have to be in the listed ad.
* Sponsored listings allows the web master to track lots of information that’s invaluable to the profitability of their business.
The biggest disadvantage, of course, is that sponsored listing costs money and in some cases can get expensive. The web master does however have complete control over how much they spend.
What’s the Cost for Pay Per Click Internet Advertising?
Since PPC advertising only charges when an Internet user clicks on the ad, the web master can choose how much they are willing to spend per click. The actual cost is based on the keywords used. As a general rule, the more popular the keyword phrase is to Internet searches, the more the cost per click (CPC). The web master bids against other web masters and the one with the higher bids gets better ad placement and page rankings.
ARM Announces 2GHz Capable Cortex-A9 Dual Core Processor Implementation
CAMBRIDGE, England--(BUSINESS WIRE)--ARM (LSE:ARM) (Nasdaq:ARMH) announced today the development of two Cortex™-A9 MPCore™ hard macro implementations for the TSMC 40nm-G process, enabling silicon manufacturers to have a rapid and low-risk route to silicon for high-performance, low-power Cortex-A9 processor-based devices. The speed-optimized hard macro implementation will enable devices to operate at frequencies greater than 2GHz.
The dual core hard macro implementations are the result of ARM’s significant investment in advanced physical IP development in unison with processor and fabric IP technology, and leading-edge implementation flows from the EDA industry. Advanced physical IP techniques have enabled critical circuits within the design to be replaced with highly tuned logic cells and memories, increasing performance while lowering overall power consumption.
Speed Optimized
The Cortex-A9 speed-optimized hard macro implementation will provide system designers with an industry standard ARM® processor incorporating aggressive low-power techniques to further extend ARM’s performance leadership into high-margin consumer and enterprise devices within the power envelope necessary for compact, high-density and thermally constrained environments. This hard macro implementation operates in excess of 2GHz when selected from typical silicon and represents an ideal solution for high-margin performance-oriented applications.
Power Optimized
In many thermally constrained applications such as set-top boxes, DTVs, printers and other feature-rich consumer and high-density enterprise applications, energy efficiency is of paramount importance. The Cortex-A9 power-optimized hard macro implementation delivers its peak performance of 4000 DMIPS while consuming less than 250mW per CPU when selected from typical silicon.
The hard macro implementations include ARM AMBA®-compliant high performance system components to maximize data traffic speed and minimize power consumption and silicon area. Each Cortex-A9 hard macro implementation also includes the CoreSight™ Program Trace Macrocell (PTM) which provides full visibility into the processor’s instruction flow, enabling the software community to develop code for optimal performance.
“The Cortex-A9 MPCore processor has already been widely accepted as the processor of choice for high-performance embedded applications across a broad spectrum of demanding consumer and enterprise devices,” said Eric Schorn, VP marketing, Processor Division, ARM. “ARM’s parallel development of advanced, optimized physical IP components demonstrates a new level of collaborative differentiation while enabling our Partners to expand their penetration into high margin domains traditionally occupied by proprietary architectures.”
“ARM’s long-standing investment in low-power leadership and ability to develop such high-performance devices enables licensees to lower the cost and risk of entering the high-margin markets currently addressed with competing proprietary solutions,” said Will Strauss, principal analyst at Forward Concepts. “With single-thread performance capable of supporting very intensive workloads, the unprecedented level of power efficiency will enable licensees to introduce compelling new products.”
“ARM and TSMC have enjoyed a long standing relationship of collaboration to ensure the development and delivery of best-in-class products optimized for our manufacturing process,” said ST Juang, senior director, Design Infrastructure Marketing Division, TSMC. “This provides OEMs developing feature-rich consumer and enterprise devices access to TSMC’s manufacturing excellence and the power of ARM processor IP.”
Both ARM dual core Cortex-A9 hard macros will share a common seven-power domain, dual-NEON™ technology configuration supporting SMP (symmetrical multiprocessing) operating systems with up to 8MB of Level2 cache memory and will be delivered with all scripts, vectors and libraries required to integrate the macro directly within any SoC device.
To enable the development of high-efficiency, low risk SoCs using other Cortex-A9 processor configurations, ARM also provides the silicon-proven SoC-level ARM Physical IP platform used to build these hard macros, and a range of AMBA-compliant system development components and tools.
In addition, the ARM Active Assist consulting service, developed in conjunction with the hard macros, enables ARM Partners to efficiently integrate the hardened macro into their SoC design to realize maximum system performance with lowest risk and fastest time-to-market.
Availability
The Cortex-A9 hard macros and the corresponding optimized physical IP used to develop the speed-optimized and power-optimized implementations are available for license today with delivery in the fourth quarter of 2009. ARM’s 40G physical IP platform is also available today at designstart.arm.com.
About ARM
ARM designs the technology that lies at the heart of advanced digital products, from wireless, networking and consumer entertainment solutions to imaging, automotive, security and storage devices. ARM’s comprehensive product offering includes 32-bit RISC microprocessors, graphics processors, video engines, enabling software, cell libraries, embedded memories, high-speed connectivity products, peripherals and development tools. Combined with comprehensive design services, training, support and maintenance, and the company’s broad Partner community, they provide a total system solution that offers a fast, reliable path to market for leading electronics companies.
The dual core hard macro implementations are the result of ARM’s significant investment in advanced physical IP development in unison with processor and fabric IP technology, and leading-edge implementation flows from the EDA industry. Advanced physical IP techniques have enabled critical circuits within the design to be replaced with highly tuned logic cells and memories, increasing performance while lowering overall power consumption.
Speed Optimized
The Cortex-A9 speed-optimized hard macro implementation will provide system designers with an industry standard ARM® processor incorporating aggressive low-power techniques to further extend ARM’s performance leadership into high-margin consumer and enterprise devices within the power envelope necessary for compact, high-density and thermally constrained environments. This hard macro implementation operates in excess of 2GHz when selected from typical silicon and represents an ideal solution for high-margin performance-oriented applications.
Power Optimized
In many thermally constrained applications such as set-top boxes, DTVs, printers and other feature-rich consumer and high-density enterprise applications, energy efficiency is of paramount importance. The Cortex-A9 power-optimized hard macro implementation delivers its peak performance of 4000 DMIPS while consuming less than 250mW per CPU when selected from typical silicon.
The hard macro implementations include ARM AMBA®-compliant high performance system components to maximize data traffic speed and minimize power consumption and silicon area. Each Cortex-A9 hard macro implementation also includes the CoreSight™ Program Trace Macrocell (PTM) which provides full visibility into the processor’s instruction flow, enabling the software community to develop code for optimal performance.
“The Cortex-A9 MPCore processor has already been widely accepted as the processor of choice for high-performance embedded applications across a broad spectrum of demanding consumer and enterprise devices,” said Eric Schorn, VP marketing, Processor Division, ARM. “ARM’s parallel development of advanced, optimized physical IP components demonstrates a new level of collaborative differentiation while enabling our Partners to expand their penetration into high margin domains traditionally occupied by proprietary architectures.”
“ARM’s long-standing investment in low-power leadership and ability to develop such high-performance devices enables licensees to lower the cost and risk of entering the high-margin markets currently addressed with competing proprietary solutions,” said Will Strauss, principal analyst at Forward Concepts. “With single-thread performance capable of supporting very intensive workloads, the unprecedented level of power efficiency will enable licensees to introduce compelling new products.”
“ARM and TSMC have enjoyed a long standing relationship of collaboration to ensure the development and delivery of best-in-class products optimized for our manufacturing process,” said ST Juang, senior director, Design Infrastructure Marketing Division, TSMC. “This provides OEMs developing feature-rich consumer and enterprise devices access to TSMC’s manufacturing excellence and the power of ARM processor IP.”
Both ARM dual core Cortex-A9 hard macros will share a common seven-power domain, dual-NEON™ technology configuration supporting SMP (symmetrical multiprocessing) operating systems with up to 8MB of Level2 cache memory and will be delivered with all scripts, vectors and libraries required to integrate the macro directly within any SoC device.
To enable the development of high-efficiency, low risk SoCs using other Cortex-A9 processor configurations, ARM also provides the silicon-proven SoC-level ARM Physical IP platform used to build these hard macros, and a range of AMBA-compliant system development components and tools.
In addition, the ARM Active Assist consulting service, developed in conjunction with the hard macros, enables ARM Partners to efficiently integrate the hardened macro into their SoC design to realize maximum system performance with lowest risk and fastest time-to-market.
Availability
The Cortex-A9 hard macros and the corresponding optimized physical IP used to develop the speed-optimized and power-optimized implementations are available for license today with delivery in the fourth quarter of 2009. ARM’s 40G physical IP platform is also available today at designstart.arm.com.
About ARM
ARM designs the technology that lies at the heart of advanced digital products, from wireless, networking and consumer entertainment solutions to imaging, automotive, security and storage devices. ARM’s comprehensive product offering includes 32-bit RISC microprocessors, graphics processors, video engines, enabling software, cell libraries, embedded memories, high-speed connectivity products, peripherals and development tools. Combined with comprehensive design services, training, support and maintenance, and the company’s broad Partner community, they provide a total system solution that offers a fast, reliable path to market for leading electronics companies.
Accelerated Designs Inc. has embedded Premier Farnell’s DesignLink into Ultra Librarian software
HUNTSVILLE, Ala.--(BUSINESS WIRE)--Accelerated Designs Inc. (ADI), a PCB Library Software and Services firm headquartered in Huntsville, AL, has completed a project to link their Ultra Librarian (UL) tool to the Premier Farnell DesignLink system. The DesignLink system is an electronic interface to the Premier Farnell electronics parts databases of Newark, Farnell, and Premier Electronics spanning Europe, the Americas and Asia Pacific. The UL product is an EDA/CAD-Independent PCB Library tool that can quickly create Parts and then Export to virtually all EDA and CAD Systems including those from Altium, Cadence, Mentor and Zuken. It contains an extensive PCB Library (Schematic Symbols and PCB Footprints) of 1.5 million Parts that can be Exported to various PCB Design flows using a free downloadable UL Reader.
"We are excited to be able to provide our customers with data directly from Premier Farnell," stated Frank Frank, President of ADI. "Now they can have Premier Farnell Part data in their schematic symbols and PCB Footprints. This will allow the customer to Export a BOM with the proper part numbers to place an order. It will help our customers create more accurate EDA CAD libraries that are rich in descriptive content. We believe customers will save time in searching and creating the critical data required to start the entire CAD design process. This relationship moves ADI and Premier Farnell closer to being able to provide our mutual customers with completed "ready to use" CAD libraries for entire manufactures series of components."
“Premier Farnell is very pleased to have Accelerated Designs Inc. embed DesignLink into its unique Ultra Librarian tool. This tool marks the first application, aside from schematic capture, to access our worldwide stores of hundreds of thousands of stocked electronic devices and make them available for association with Accelerated Designs Inc.’s library of ubiquitous schematic symbols and footprints. We think Ultra Librarian will help our customers wishing to separate the job of parts management from specific CAD tool environments,” said Randall Restle, Director of Global Technical Marketing for Premier Farnell.
ADI will be working with Premier Farnell to make the 1.5M Part library available to all Premier Farnell customers that register and download the Free UL Reader. The Library will initially consist of Semiconductors and Connector Parts from such companies as National Semiconductor, Microchip, Linear Technology, Altera, Maxim, Xilinx and others. It is estimated that the Library of parts could save weeks of time on a project vs. building them from scratch.
About Accelerated Designs
Accelerated Designs, Inc. is a privately held company located it Huntsville, Alabama. It provides integrated circuit vendors, electronic manufacturers and electronic engineers with a one-stop source of data for all computer-aided design (CAD), simulation, 3D models and other engineering data in a form that allows them to customize the data to meet their own company requirements and the requirements of their customers. Its industrial-sized library tool, Ultra Librarian, and an existing library of 1.5 million electronic design automation CAD parts can be ported to any CAD tool. Additional company information is available at www.accelerated-designs.com.
"We are excited to be able to provide our customers with data directly from Premier Farnell," stated Frank Frank, President of ADI. "Now they can have Premier Farnell Part data in their schematic symbols and PCB Footprints. This will allow the customer to Export a BOM with the proper part numbers to place an order. It will help our customers create more accurate EDA CAD libraries that are rich in descriptive content. We believe customers will save time in searching and creating the critical data required to start the entire CAD design process. This relationship moves ADI and Premier Farnell closer to being able to provide our mutual customers with completed "ready to use" CAD libraries for entire manufactures series of components."
“Premier Farnell is very pleased to have Accelerated Designs Inc. embed DesignLink into its unique Ultra Librarian tool. This tool marks the first application, aside from schematic capture, to access our worldwide stores of hundreds of thousands of stocked electronic devices and make them available for association with Accelerated Designs Inc.’s library of ubiquitous schematic symbols and footprints. We think Ultra Librarian will help our customers wishing to separate the job of parts management from specific CAD tool environments,” said Randall Restle, Director of Global Technical Marketing for Premier Farnell.
ADI will be working with Premier Farnell to make the 1.5M Part library available to all Premier Farnell customers that register and download the Free UL Reader. The Library will initially consist of Semiconductors and Connector Parts from such companies as National Semiconductor, Microchip, Linear Technology, Altera, Maxim, Xilinx and others. It is estimated that the Library of parts could save weeks of time on a project vs. building them from scratch.
About Accelerated Designs
Accelerated Designs, Inc. is a privately held company located it Huntsville, Alabama. It provides integrated circuit vendors, electronic manufacturers and electronic engineers with a one-stop source of data for all computer-aided design (CAD), simulation, 3D models and other engineering data in a form that allows them to customize the data to meet their own company requirements and the requirements of their customers. Its industrial-sized library tool, Ultra Librarian, and an existing library of 1.5 million electronic design automation CAD parts can be ported to any CAD tool. Additional company information is available at www.accelerated-designs.com.
Wednesday, September 23, 2009
X-FAB Announces New Process Design Kits for Cadence Virtuoso IC 6.1 Custom Design Platform
TheKit Now Available for All X-FAB Technology Platforms; Increases Productivity for Analog/Mixed-Signal Designs
ERFURT, Germany--(BUSINESS WIRE)--X-FAB Silicon Foundries, the world's leading foundry for the production of analog/mixed-signal integrated circuits, today announced the availability of comprehensive process design kits (PDK), branded as TheKit, based on the Cadence® Design Systems Virtuoso® IC 6.1 custom design platform and SKILL programming language. TheKit, with best-in-class SKILL PDK, is available for all of X-FAB’s process technologies from 1.0 um down to 0.18 um, and offers a smooth and easy migration from existing projects developed with Virtuoso IC 5.1 to Virtuoso IC 6.1. Its automatic project setup including libraries and default tool settings ensures a seamless design flow that saves setup time. Using TheKit, X-FAB’s customers can benefit from productivity gains, faster time to market and lower risk.
X-FAB developed TheKit for the latest release of the Cadence Virtuoso custom design platform, IC 6.1, to help its customers reduce design time, and to ensure manufacturing-robust designs. With the help of the SKILL language, TheKit supports advanced interactive and automated technologies, such as Cadence Virtuoso Analog Design Environment XL/GXL, for a fast and accurate verification and yield optimization. X-FAB uses the Virtuoso AMS Designer as a simulation hub to link advanced analog and digital simulation engines into a seamless mixed-signal verification environment. For a full automated routing of custom ICs at any level of the design hierarchy, X-FAB supports Virtuoso routing technologies. To ensure a successful production tape-out and to make use of a solution that offers competitive single-processor and distributed processor performance during physical verification, X-FAB relies on the Cadence Physical Verification System.
Thomas P. Beckley, Corporate Vice President - Custom IC Engineering at Cadence Design Systems said: “With X-FAB supporting the latest Virtuoso custom design platform, their customers will benefit from the next level of design automation for analog/mixed-signal design. Besides time-to-market, high quality of silicon is everyone’s concern. By using SKILL as part of the PDK, they enable our GXL technologies including our DFM tools so our mutual customers can optimize their yield.”
X-FAB offers several digital libraries in the Cadence environment optimized for low power, low noise, high density and timing to allow customers to select the most appropriate devices for their specific applications. A large portfolio of analog libraries (e.g., DAC, ADC, OpAmps, Bandgaps, Oscillators), embedded non-volatile memory (NVM) IP such as eFlash, EEPROM and NV latches is available for X-FAB’s technology platforms. Two important design aspects are electrostatic discharge (ESD) robustness and Safe Operating Area (SOA) check. To address the first aspect, X-FAB provides a special tool called ESD-Design-Checker to identify possible ESD weaknesses on schematic level and to estimate the ESD robustness that can be expected for the design. For SOA checks, X-FAB provides additional SPICE models to check whether all primitive devices are operating within permitted ranges.
Dr. Jens Kosch, chief technology officer at X-FAB, said: “Time-to-market is the most critical success factor for our customers. A seamless design flow supporting the latest design methodologies, combined with our state-of-the-art process design kit, perfectly aligns with our customers’ requirements.”
X-FAB also leverages the new Incremental Technology Database (ITDB), based on Open Access, which is a technology library enabling CAD group/users to add or modify technology parameters without violating the original foundry design rules. It simplifies the data management and requires less disk space, especially for processes that have many derivatives. The main foundry technology library is referenced and individual constraints can be overridden if they do not violate the basic minimum rules in the ITDB.
Both X-FAB and Cadence are participating in the SAME Forum & Conference in Sophia-Antipolis, France, Sept. 22-23, 2009. Please visit X-FAB at Booth #14 to discuss its latest process design kits.
About X-FAB
X-FAB is the leading analog/mixed-signal foundry group manufacturing silicon wafers for analog-digital integrated circuits (mixed-signal ICs). X-FAB maintains wafer production facilities in Erfurt and Dresden (Germany), Plymouth (UK), Lubbock, Texas (US) and Kuching, Sarawak (Malaysia), and employs approximately 2,600 people worldwide. Wafers are manufactured based on advanced modular CMOS and BiCMOS processes with technologies ranging from 1.0 to 0.18 micrometers, for applications primarily in the automotive, communications, consumer and industrial sectors. For more information, please visit www.xfab.com.
ERFURT, Germany--(BUSINESS WIRE)--X-FAB Silicon Foundries, the world's leading foundry for the production of analog/mixed-signal integrated circuits, today announced the availability of comprehensive process design kits (PDK), branded as TheKit, based on the Cadence® Design Systems Virtuoso® IC 6.1 custom design platform and SKILL programming language. TheKit, with best-in-class SKILL PDK, is available for all of X-FAB’s process technologies from 1.0 um down to 0.18 um, and offers a smooth and easy migration from existing projects developed with Virtuoso IC 5.1 to Virtuoso IC 6.1. Its automatic project setup including libraries and default tool settings ensures a seamless design flow that saves setup time. Using TheKit, X-FAB’s customers can benefit from productivity gains, faster time to market and lower risk.
X-FAB developed TheKit for the latest release of the Cadence Virtuoso custom design platform, IC 6.1, to help its customers reduce design time, and to ensure manufacturing-robust designs. With the help of the SKILL language, TheKit supports advanced interactive and automated technologies, such as Cadence Virtuoso Analog Design Environment XL/GXL, for a fast and accurate verification and yield optimization. X-FAB uses the Virtuoso AMS Designer as a simulation hub to link advanced analog and digital simulation engines into a seamless mixed-signal verification environment. For a full automated routing of custom ICs at any level of the design hierarchy, X-FAB supports Virtuoso routing technologies. To ensure a successful production tape-out and to make use of a solution that offers competitive single-processor and distributed processor performance during physical verification, X-FAB relies on the Cadence Physical Verification System.
Thomas P. Beckley, Corporate Vice President - Custom IC Engineering at Cadence Design Systems said: “With X-FAB supporting the latest Virtuoso custom design platform, their customers will benefit from the next level of design automation for analog/mixed-signal design. Besides time-to-market, high quality of silicon is everyone’s concern. By using SKILL as part of the PDK, they enable our GXL technologies including our DFM tools so our mutual customers can optimize their yield.”
X-FAB offers several digital libraries in the Cadence environment optimized for low power, low noise, high density and timing to allow customers to select the most appropriate devices for their specific applications. A large portfolio of analog libraries (e.g., DAC, ADC, OpAmps, Bandgaps, Oscillators), embedded non-volatile memory (NVM) IP such as eFlash, EEPROM and NV latches is available for X-FAB’s technology platforms. Two important design aspects are electrostatic discharge (ESD) robustness and Safe Operating Area (SOA) check. To address the first aspect, X-FAB provides a special tool called ESD-Design-Checker to identify possible ESD weaknesses on schematic level and to estimate the ESD robustness that can be expected for the design. For SOA checks, X-FAB provides additional SPICE models to check whether all primitive devices are operating within permitted ranges.
Dr. Jens Kosch, chief technology officer at X-FAB, said: “Time-to-market is the most critical success factor for our customers. A seamless design flow supporting the latest design methodologies, combined with our state-of-the-art process design kit, perfectly aligns with our customers’ requirements.”
X-FAB also leverages the new Incremental Technology Database (ITDB), based on Open Access, which is a technology library enabling CAD group/users to add or modify technology parameters without violating the original foundry design rules. It simplifies the data management and requires less disk space, especially for processes that have many derivatives. The main foundry technology library is referenced and individual constraints can be overridden if they do not violate the basic minimum rules in the ITDB.
Both X-FAB and Cadence are participating in the SAME Forum & Conference in Sophia-Antipolis, France, Sept. 22-23, 2009. Please visit X-FAB at Booth #14 to discuss its latest process design kits.
About X-FAB
X-FAB is the leading analog/mixed-signal foundry group manufacturing silicon wafers for analog-digital integrated circuits (mixed-signal ICs). X-FAB maintains wafer production facilities in Erfurt and Dresden (Germany), Plymouth (UK), Lubbock, Texas (US) and Kuching, Sarawak (Malaysia), and employs approximately 2,600 people worldwide. Wafers are manufactured based on advanced modular CMOS and BiCMOS processes with technologies ranging from 1.0 to 0.18 micrometers, for applications primarily in the automotive, communications, consumer and industrial sectors. For more information, please visit www.xfab.com.
SPIRIT’s Wideband Voice Engine Powers snom’s Enterprise-Grade VoIP Phones
MOSCOW & BERLIN--(BUSINESS WIRE)--SPIRIT DSP, the world's leading provider of carrier-grade voice and video software engines, announced today that snom technology AG, a leading developer and manufacturer of advanced Voice over IP phones, has licensed SPIRIT’s TeamSpirit® Voice Engine Embedded to ensure HD Audio (snom klarVOICE) in its advanced touch screen desktop IP-phone snom 870, successfully launched this July in the USA, and in subsequent products.
Brand new snom 870 was designed for information-rich business activities and targeted at enterprise, as well as small and mid-sized businesses markets. ARM-based snom 870 is a fourth generation SIP phone with modern elegant design and extended multimedia capabilities. This “smart” end-user terminal features a number of carrier-supported business-crucial IP-services and applications, like HD Audio quality IP-telephony, Unified Communications and Customer Relationship Management.
Recognized in the industry as the home of one of the most optimized and power-efficient audio and video processing solutions, SPIRIT brings HD Audio and Video to numerous innovative Internet-based services, endpoint terminals and chips by world leading carriers, OEMs, software and semiconductor vendors, including Adobe, ARM, AT&T, BT, China Telecom, Freescale, France Telecom, Huawei, iRiver, Korea Telecom, NTT, Oracle, Radvision, Samsung, Skype, RMI, STMicroelectronics, Tensilica, Texas Instruments, Toshiba, ZTE etc. SPIRIT Engines’ compliance with international quality standards and carriers’ requirements to communication terminals helped snom to pass multiple audio tests for narrowband and wideband speech at the Head Acoustics GmbH.
“Wideband VoIP represents the next step in the evolution of IP telephony, enabling the delivery of phone conversations with crystal clear audio quality,” said Dr. Michael Knieling, Executive Vice President of Marketing and Sales of snom. “The combination of SPIRIT’s cutting-edge technology with snom’s 870 design offers a powerful cooperation resulting in meeting the high standard that snom customers have come to expect. With the proven SPIRIT’s voice processing inside we can confidently provide our enterprise customers with the crystal clear HD Audio conversations even over the congested networks.”
“We are pleased to partner with snom, a world famous developer of SIP phones, which combine advanced IP telephony features and elegant design with an affordable cost”, said Alex Kravchenko, General Manager at SPIRIT. "snom’s new IP-phone successfully blends high quality HD Audio delivered by the comprehensive set of advanced voice processing technologies, packed into the SPIRIT’s Engine, with a great variety of innovative IP-based business services and applications. "Smart" SPIRIT’s software, that complements and amplifies network-specific QoS, turns snom 870 into a “smart" high-end user terminal, delivering wideband voice over congested networks."
About snom
snom technology AG develops and manufactures Voice-over-IP (VoIP) telephones and related equipment based on the IETF open standard, SIP (Session Initiation Protocol). Recognized for its high quality, customizable and cost-effective business solutions, snom is also differentiated by the company’s history in the VoIP industry, and its dedication to high security standards. All of snom’s software exists in the firmware on the phones – making it easier for users to download updates and new features. snom customers benefit from the interoperability and flexibility that the snom telephones offer, including plug and play integration and universal compatibility with any SIP-based telephony platform. Founded in 1996 and headquartered in Berlin, Germany, snom technology AG also has a offices in Milan, Italy, Paris, France and in Boston, USA. The company distributes its fourth generation SIP phones through its network of authorized reseller partners in Europe, South America, Asia-Pac, Africa and Australia. For more information on snom, please visit www.snom.com
About SPIRIT
SPIRIT DSP (www.spiritDSP.com) is the world's leading provider of carrier-grade voice, video and audio communication software engines since 1996. SPIRIT communication software is used in over 80 countries and powers more than 100 million voice channels. SPIRIT counts among its customers and deployments Adobe, ARM, AT&T, Blizzard, BT, China Mobile, China Telecom, Cisco, Compal, Ericsson, France Telecom, HP, HTC, Huawei, Korea Telecom, Kyocera, LG-Nortel, LG-Dacom, Microsoft, NEC, NTT, Oracle, Polycom, Radvision, Reigncom (iRiver), Samsung, Siemens, Skype, Texas Instruments, Toshiba, ZTE, and 200+ other telcos, OEMs, semiconductors and software vendors. SPIRIT smart-phone OEM customers’ shipments jointly exceed 60% share of the global market.
Brand new snom 870 was designed for information-rich business activities and targeted at enterprise, as well as small and mid-sized businesses markets. ARM-based snom 870 is a fourth generation SIP phone with modern elegant design and extended multimedia capabilities. This “smart” end-user terminal features a number of carrier-supported business-crucial IP-services and applications, like HD Audio quality IP-telephony, Unified Communications and Customer Relationship Management.
Recognized in the industry as the home of one of the most optimized and power-efficient audio and video processing solutions, SPIRIT brings HD Audio and Video to numerous innovative Internet-based services, endpoint terminals and chips by world leading carriers, OEMs, software and semiconductor vendors, including Adobe, ARM, AT&T, BT, China Telecom, Freescale, France Telecom, Huawei, iRiver, Korea Telecom, NTT, Oracle, Radvision, Samsung, Skype, RMI, STMicroelectronics, Tensilica, Texas Instruments, Toshiba, ZTE etc. SPIRIT Engines’ compliance with international quality standards and carriers’ requirements to communication terminals helped snom to pass multiple audio tests for narrowband and wideband speech at the Head Acoustics GmbH.
“Wideband VoIP represents the next step in the evolution of IP telephony, enabling the delivery of phone conversations with crystal clear audio quality,” said Dr. Michael Knieling, Executive Vice President of Marketing and Sales of snom. “The combination of SPIRIT’s cutting-edge technology with snom’s 870 design offers a powerful cooperation resulting in meeting the high standard that snom customers have come to expect. With the proven SPIRIT’s voice processing inside we can confidently provide our enterprise customers with the crystal clear HD Audio conversations even over the congested networks.”
“We are pleased to partner with snom, a world famous developer of SIP phones, which combine advanced IP telephony features and elegant design with an affordable cost”, said Alex Kravchenko, General Manager at SPIRIT. "snom’s new IP-phone successfully blends high quality HD Audio delivered by the comprehensive set of advanced voice processing technologies, packed into the SPIRIT’s Engine, with a great variety of innovative IP-based business services and applications. "Smart" SPIRIT’s software, that complements and amplifies network-specific QoS, turns snom 870 into a “smart" high-end user terminal, delivering wideband voice over congested networks."
About snom
snom technology AG develops and manufactures Voice-over-IP (VoIP) telephones and related equipment based on the IETF open standard, SIP (Session Initiation Protocol). Recognized for its high quality, customizable and cost-effective business solutions, snom is also differentiated by the company’s history in the VoIP industry, and its dedication to high security standards. All of snom’s software exists in the firmware on the phones – making it easier for users to download updates and new features. snom customers benefit from the interoperability and flexibility that the snom telephones offer, including plug and play integration and universal compatibility with any SIP-based telephony platform. Founded in 1996 and headquartered in Berlin, Germany, snom technology AG also has a offices in Milan, Italy, Paris, France and in Boston, USA. The company distributes its fourth generation SIP phones through its network of authorized reseller partners in Europe, South America, Asia-Pac, Africa and Australia. For more information on snom, please visit www.snom.com
About SPIRIT
SPIRIT DSP (www.spiritDSP.com) is the world's leading provider of carrier-grade voice, video and audio communication software engines since 1996. SPIRIT communication software is used in over 80 countries and powers more than 100 million voice channels. SPIRIT counts among its customers and deployments Adobe, ARM, AT&T, Blizzard, BT, China Mobile, China Telecom, Cisco, Compal, Ericsson, France Telecom, HP, HTC, Huawei, Korea Telecom, Kyocera, LG-Nortel, LG-Dacom, Microsoft, NEC, NTT, Oracle, Polycom, Radvision, Reigncom (iRiver), Samsung, Siemens, Skype, Texas Instruments, Toshiba, ZTE, and 200+ other telcos, OEMs, semiconductors and software vendors. SPIRIT smart-phone OEM customers’ shipments jointly exceed 60% share of the global market.
ON Semiconductor Announces Expansion of PureEdgeTM Family of Single- and Dual-Frequency Crystal Oscillator Modules with LVDS Interface
Single- and Dual-Frequency Oscillator Modules Deliver High Precision Performance for LVDS and LVPECL 2.5 V and 3.3 V Clock Generation Applications
PHOENIX--(BUSINESS WIRE)--ON Semiconductor (Nasdaq: ONNN), a leading global supplier of high performance, energy efficient, silicon solutions, has expanded its PureEdge™ family of high accuracy crystal oscillator (XO) clock modules. The new high precision devices provide total frequency stability of ±50 parts per million (ppm) and will meet clock generation requirements in next generation low-voltage differential signaling (LVDS) and low-voltage positive emitter coupled logic (LVPECL) designs.
The NBXzzzzzz series of single- and dual-frequency modules provide ultra low jitter and ultra low phase noise LVDS and LVPECL differential outputs respectively. Applications include frequency control and high accuracy clock trees in high speed LAN and WAN networking equipment, telecom base stations, storage systems and high-end computing platforms.
All of the new modules use a low frequency, high Q fundamental mode crystal and analog Phase Lock Loop (PLL) multiplier to provide the high accuracy single- or dual-output frequency. Typical RMS phase jitter is rated at just 0.5 picoseconds (ps) when output Single Side Band (SSB) is integrated between 12 kilohertz (kHz) and 20 megahertz (MHz). Output frequency options for single-frequency modules are 161.13 MHz; 175.00 MHz; 187.50 MHz; 340.00 MHz; 425.00 MHz; 622.08 MHz. Dual-frequency modules offer user selectable output frequency of 106.25 MHz/212.50 MHz; 125 MHz/250 MHz; 155.52 MHz/311.04 MHz; 156.25 MHz/312.50 MHz; 200.00 MHz/400.00 MHz. As a result, designers can choose modules that are optimized for a variety of specific protocols including Ethernet, Gigabit Ethernet, 1x and 2x Fibre Channel, SATA, SONET/SDH and PCIe.
Device
Output Frequency
(MHz)
Total Frequency Stability
(+/-PPM)
Power
Supply (V)
Interface
Technology
Application
NBXSPA008LNHTAG 161.1328 50 2.5 / 3.3 LVDS
Networking, 10GE, 10G LAN
NBXDPA012LNHTAG 106.25 / 212.50 50 2.5 / 3.3 LVDS
1x, 2x Fibre Channel
NBXDPA015LNHTAG 200.00 / 400.00 50 2.5 / 3.3 LVDS Servers, Networking, Host Bus Adapter
NBXDPA017LNHTAG 156.25 / 312.50 50 2.5 / 3.3 LVDS Ethernet, Networking
NBXDPA018LNHTAG 155.52 / 311.04 50 2.5 / 3.3 LVDS SONET, SDH, Telecom
NBXDPA019LNHTAG 125.00 / 250.00 50 2.5 / 3.3 LVDS PCIe, PCI, High-End Computing, Networking
NBXSPA022LNHTAG 187.50 50 2.5 / 3.3 LVDS 12 Gb/s Ethernet Clock
NBXSBA024LNHTAG 622.08 50 2.5 / 3.3 LVPECL SONET OC-192, Telecom
NBXSBA025LNHTAG 425.00 50 2.5 / 3.3 LVPECL
4x Fibre Channel
NBXSBA030LNHTAG 175.00 50 2.5 / 3.3 LVPECL Networking, ASIC
NBXSBA031LNHTAG
340.00
50 2.5 / 3.3 LVPECL Networking, PON, Mixer
“Delivering high precision across a variety of operating conditions, ON Semiconductor’s latest PureEdge clock modules provide the accuracy and reliability demanded by new and emerging LVDS and LVPECL clock tree designs,” said Ryan Cameron, director, custom industrial and timing products business unit at ON Semiconductor. “What’s more, these silicon based devices are simpler to manufacture and offer more flexibility with better performance and lead time than conventional quartz-based alternatives, helping OEMs to reduce costs without sacrificing performance.”
All of the new modules operate from a 2.5 volts (V) and 3.3 V input voltage and are supplied in a hermetically sealed 5.0 mm x 7.0 mm x 1.90 mm ceramic CLCC-6 SMD package.
Pricing and Availability
Budgetary pricing for these modules is $4.50 for quantities of 100 units. For more information, please contact Senad Lomigora at Senad.Lomigora@onsemi.com.
For additional technical information, visit http://www.onsemi.com.
About ON Semiconductor
With its global logistics network and broad product portfolio, ON Semiconductor (Nasdaq: ONNN) is a preferred supplier of high performance, energy efficient, silicon solutions that enable designers to quickly and cost-effectively improve system efficiency for electronics in the computing, communications, consumer, automotive, industrial, medical and military/aerospace markets. The company’s portfolio includes power management, signal, logic, discrete and custom devices. The company operates a network of manufacturing facilities, sales offices, and design centers in key markets throughout North America, Europe, and the Asia Pacific regions. For more information,
PHOENIX--(BUSINESS WIRE)--ON Semiconductor (Nasdaq: ONNN), a leading global supplier of high performance, energy efficient, silicon solutions, has expanded its PureEdge™ family of high accuracy crystal oscillator (XO) clock modules. The new high precision devices provide total frequency stability of ±50 parts per million (ppm) and will meet clock generation requirements in next generation low-voltage differential signaling (LVDS) and low-voltage positive emitter coupled logic (LVPECL) designs.
The NBXzzzzzz series of single- and dual-frequency modules provide ultra low jitter and ultra low phase noise LVDS and LVPECL differential outputs respectively. Applications include frequency control and high accuracy clock trees in high speed LAN and WAN networking equipment, telecom base stations, storage systems and high-end computing platforms.
All of the new modules use a low frequency, high Q fundamental mode crystal and analog Phase Lock Loop (PLL) multiplier to provide the high accuracy single- or dual-output frequency. Typical RMS phase jitter is rated at just 0.5 picoseconds (ps) when output Single Side Band (SSB) is integrated between 12 kilohertz (kHz) and 20 megahertz (MHz). Output frequency options for single-frequency modules are 161.13 MHz; 175.00 MHz; 187.50 MHz; 340.00 MHz; 425.00 MHz; 622.08 MHz. Dual-frequency modules offer user selectable output frequency of 106.25 MHz/212.50 MHz; 125 MHz/250 MHz; 155.52 MHz/311.04 MHz; 156.25 MHz/312.50 MHz; 200.00 MHz/400.00 MHz. As a result, designers can choose modules that are optimized for a variety of specific protocols including Ethernet, Gigabit Ethernet, 1x and 2x Fibre Channel, SATA, SONET/SDH and PCIe.
Device
Output Frequency
(MHz)
Total Frequency Stability
(+/-PPM)
Power
Supply (V)
Interface
Technology
Application
NBXSPA008LNHTAG 161.1328 50 2.5 / 3.3 LVDS
Networking, 10GE, 10G LAN
NBXDPA012LNHTAG 106.25 / 212.50 50 2.5 / 3.3 LVDS
1x, 2x Fibre Channel
NBXDPA015LNHTAG 200.00 / 400.00 50 2.5 / 3.3 LVDS Servers, Networking, Host Bus Adapter
NBXDPA017LNHTAG 156.25 / 312.50 50 2.5 / 3.3 LVDS Ethernet, Networking
NBXDPA018LNHTAG 155.52 / 311.04 50 2.5 / 3.3 LVDS SONET, SDH, Telecom
NBXDPA019LNHTAG 125.00 / 250.00 50 2.5 / 3.3 LVDS PCIe, PCI, High-End Computing, Networking
NBXSPA022LNHTAG 187.50 50 2.5 / 3.3 LVDS 12 Gb/s Ethernet Clock
NBXSBA024LNHTAG 622.08 50 2.5 / 3.3 LVPECL SONET OC-192, Telecom
NBXSBA025LNHTAG 425.00 50 2.5 / 3.3 LVPECL
4x Fibre Channel
NBXSBA030LNHTAG 175.00 50 2.5 / 3.3 LVPECL Networking, ASIC
NBXSBA031LNHTAG
340.00
50 2.5 / 3.3 LVPECL Networking, PON, Mixer
“Delivering high precision across a variety of operating conditions, ON Semiconductor’s latest PureEdge clock modules provide the accuracy and reliability demanded by new and emerging LVDS and LVPECL clock tree designs,” said Ryan Cameron, director, custom industrial and timing products business unit at ON Semiconductor. “What’s more, these silicon based devices are simpler to manufacture and offer more flexibility with better performance and lead time than conventional quartz-based alternatives, helping OEMs to reduce costs without sacrificing performance.”
All of the new modules operate from a 2.5 volts (V) and 3.3 V input voltage and are supplied in a hermetically sealed 5.0 mm x 7.0 mm x 1.90 mm ceramic CLCC-6 SMD package.
Pricing and Availability
Budgetary pricing for these modules is $4.50 for quantities of 100 units. For more information, please contact Senad Lomigora at Senad.Lomigora@onsemi.com.
For additional technical information, visit http://www.onsemi.com.
About ON Semiconductor
With its global logistics network and broad product portfolio, ON Semiconductor (Nasdaq: ONNN) is a preferred supplier of high performance, energy efficient, silicon solutions that enable designers to quickly and cost-effectively improve system efficiency for electronics in the computing, communications, consumer, automotive, industrial, medical and military/aerospace markets. The company’s portfolio includes power management, signal, logic, discrete and custom devices. The company operates a network of manufacturing facilities, sales offices, and design centers in key markets throughout North America, Europe, and the Asia Pacific regions. For more information,
Pedestal Mounted Air Defense System
Able to fire up to eight Stinger missiles – each traveling
at Mach 2.2 – the Turkish Armed Forces Pedestal
Mounted Air Defense System (PMADS) delivers
supersonic short-range air defense capabilities for
troops in exposed positions.
Its tactical importance on the battlefield is, however,
only matched by its strategic importance to Turkey’s
national defense industry. After years of manufacturing
defense systems under license, the PMADS program is
the first to be placed with a Turkish company taking the
lead as prime contractor.
As that prime contractor, Aselsan Electronic Industry Inc.
has created an advanced vehicle mounted stinger
platform that delivers significant advantages over the
previous ManPortable Air Defense System (MANPADS)
used by the Turkish Army. In doing so, the company
turned to Radstone Technology to provide the Fire
Control System that lies at the heart of the program.
Faced with the need to deliver uncompromising quality
and reliability as cost-effectively as possible, Radstone
has combined its advanced systems-level expertise with
innovative techniques it has been developing to reduce
costs, weight and production lead times by 30 percent.
“Radstone’s people are very professional,” explains
Mustafa Kaval, Aselsan’s Project Manager for the PMADS
program. “They are technically excellent and have been
very supportive, giving good answers to any questions.
Not only was this our largest-ever weapons systems
integration program, it was our first using COTS. We
needed technology and we needed support that we could
rely on – and Radstone have delivered both.”
Strategic Procurement Policy
The responsibility for coordinating Turkey's large scale
and foreign defense industry and procurement process
lies with the country’s Under Secretariat for Defense
Industries (SSM), an autonomous agency created in 1985
within the Defense Ministry.
In 1997, while announcing that Turkey's annual defense
spending was set to rise steadily to reach a total of $31
billion during the next ten years and as much as $150
billion through to 2025, SSM explained that the spending
would be accompanied by an increasingly stringent
policy of local production to meet the country's defense
procurement needs.
“We have used the last ten to twelve years to establish
our productive defense infrastructure in Turkey. We are
now ready to tackle design and integration capabilities –
goals which the Turkish armed forces fully support,” said
Veysel Yayan, Deputy Under Secretary at SSM at the
time.
The first program to benefit from this strategy
was PMADS. For some years Turkey had
procured a MANPADS version of the
Stinger missile as part of an international
consortium with the Netherlands,
Germany, and Greece. Within that program,
Aselsan produced an electronic guidance
section of the Stinger missile.
Aselsan – A Leading Electronics
Company
Aselsan was founded in 1975 by the Turkish Armed
Forces Foundation to produce tactical military radios and
defense electronic systems for the Turkish Army. Today
Aselsan is the country’s leading multi-product electronics
company, designing, developing and manufacturing
modern electronic systems for military and professional
customers.
Headquartered in Ankara, the company operates through
three main divisions. They are
Communications, covering military and professional
communications systems
• Guidance and Electro-Optics, which manufactures
hybrid microelectronic circuits, night vision
equipment, thermal cameras, laser ranger/designators
and inertial navigation systems
• Microwave and System Technologies, which is
primarily focused on radar, electronic warfare and
command-control systems.
In 1992 SSM commissioned Aselsan to undertake a
feasibility study on the design and production of a
pedestal mounted platform for Stinger missiles which
could be used on two different vehicle platforms.
The ZIPKIN would be based on a fourwheel
Land Rover Defender, while
the ATILGAN would be based on an
armored/tracked M113A2 personnel
carrier.
Aselsan was already very familiar
with the program having started
conceptual studies in 1989 to help
define requirements and how best to
meet them. Kaval, who works in
the Microwave and System
Technologies Division, explains
the drivers for the program. “The
key objectives were to overcome
the limitations of MANPADS,
primarily the fact that the manoperated
system can only fire one missile at
a time and its accuracy is dependent on the skill of
the operator. Our brief was to create an easy to deploy
and fast moving platform that could fire multiple missiles
and be integrated into a single command control system.”
Radstone Provides Development
Platform
PMADS comprises a number of advanced subsystems,
from thermal imaging to a laser rangefinder and the Fire
Control System. “The Fire Control System is actually the
heart of the entire platform,” explains Kaval. “At that time
our systems design experience had been focused
primarily on applications running on PCs. This was to be
our first rugged project and we wanted a vendor that
could not only provide a complete solution for the FCS,
but one that could support us through the development.”
After an exhaustive study, Aselsan concluded that
Radstone was the only company with the board level and
system level expertise required to partner them through
the development program. As the world’s leading
independent supplier of rugged, high-performance COTS
embedded computer products, subsystems and support
software for defense and aerospace applications,
Radstone’s portfolio extends from systems chassis to
boards and completely integrated systems.
But it wasn’t just the technology that attracted Aselsan.
“Radstone offered a very competitively priced solution,
but for me what was even more important was the
support that they showed. They were willing to work
directly with us, without an agent, and even in those
early stages they proved that they could work well with
our engineers.”
The contract was
placed with Radstone
in 1996 to supply a fully
integrated system for the FCS.
It proved to be a sound decision,
especially as Aselsan had only two
and a half years in which to complete
the entire design and development phase, culminating in
a firing range field test.
“It was a very challenging timescale,” recalls Kaval,
“because we not only had to design and integrate all the
subsystems, we also needed to select the best vendors
and complete negotiations with them for each of the
subsystems as well as integrating them into the overall
PMADS system.”
To ease development times, Radstone provided Aselsan
with commercial versions of the boards that would
comprise the final rugged system. Asked how important
those boards were, Kaval is unhesitating. “They were
very, very important. Without that commercial platform
we would not have been able to start our software
development. As soon as we received the platform we
were able to start work on writing our software which
enabled us to shorten the development process by about
six months, so it was critical.”
The completion of the development phase was a series of
demanding firing range tests with the system firing –
while stationary and on the move – targets comprising
metal plates set up on distant hillsides and in-flight
drones. Aselsan and senior observers from the Turkish
Army and SSM were delighted to witness 100 percent
success in all nine test firings.
With this success came the formal completion of the
development phase and negotiations began between
Aselsan and SSM on the exact number of systems
required and other details. “We signed the production
contract in November 2001,” recalls Kaval, “and
Radstone was the first supplier we started to talk to about
the production system.”
Significant Advances in Production
System
With over 40 years serving the military marketplace,
Radstone understands better than most the challenges
posed by the use of COTS components in military
systems destined not only to operate in hostile
environments, but in programs with lifespan stretching up
to 25 years.
The company’s response has been to develop its concept
of Whole Program Life COTS™ which aims to reduce
overall cost of ownership and provide industry-leading
safeguards against obsolescence. It does so by addressing
the issue at all stages of the program lifecycle, from
designed-in compatibility across generations of products
through to a highly resourced team of design engineers
and support staff dedicated solely to supporting programs
throughout their extended lives.
Part of this approach is a strict policy of maintaining the
‘form, fit, and function’ of boards across generations of
silicon to provide ‘plug and play’ processor upgrades.
While the development system used its PowerPC2A
Single Board Computer (SBC), for the production system
Radstone was able to recommend an immediate upgrade
to the latest generation PowerPC4A.
“I very much agree with Radstone’s policy of maintaining
form, fit and function,” observes Kaval. “Radstone are
leaders in guarding against obsolescence and while we
did not need the performance gains the new processor
offered, it is a very useful means of combating
component obsolescence.”
Radstone’s innovation didn’t stop with a processor
upgrade, however, as the company’s designers worked
with their counterparts in Aselsan to introduce to the
system a range of techniques that Radstone had been
working on.
New Chassis Construction
Among the first improvements was the use of a new
chassis construction method. Previously, Radstone used a
dip brazing process to solder the aluminum walls of a
chassis together to create a very strong enclosure.
However, this method requires the various parts to be
assembled on a jig and moved to a brazing oven where
the temperature needed approaches the melting point of
aluminum. The unavoidable distortion that frequently
results from this method therefore required a postbonding
machining operation.
Transferring lessons learned from another program it had
worked on, Radstone has developed a new way of
bonding the chassis using high performance bonding
agents first developed and used in the aviation industry.
The new technique delivers a chassis with the same
mechanical, environmental and EMC performance as the
dip-brazing method, but in a far more controlled
production process without the need for post-brazing
machining.
Customized Power – off-the-shelf
The power supply for any integrated system typically
represents some 30 percent of total system cost. Radstone
offers a range of power supplies meeting MIL-STD-704E.
However, the vehicle generator environment of the
PMADS meant that Aselsan required a power supply that
met MIL-STD-1275B, where the low voltage operating
level is lower and the spikes and transients are much
more severe – +/-250volt 100micro sec spikes and
100volt 50msec transients.
To meet this requirement Radstone took advantage of a
new approach to power supplies it was developing. The
objective was to break away from the traditional ‘fixed
configuration’ model and derive a cost effective way of
offering flexibility in terms of both Power Supply Unit
(PSU) input specification and output voltage rail
configuration.
To achieve this, Radstone has developed an innovative
approach to power supplies by specifying and then
sourcing a range of power modules which it can ‘mix
and match’ to create a bespoke design that meets a
customer’s precise needs. This means, for example, that if
a customer does not need a particular voltage rail then
they do not have to pay for it merely because it is part of
the ‘standard item’. And in Aselsan’s case, this modular
approach enabled Radstone to design and build a power
supply that met the customer’s particular requirement for
bespoke voltage rail power sequencing and also for the
facility to upgrade in the future to 3.3 volts – something
that would have been impossible in a pre-built
configuration. And because each module is a proven
item, each new power supply configuration carries
inherently less risk than a new design.
Custom 19-layer Backplane and Front
Panel Flex-Circuits
For the development of the prototype system, Radstone
provided an ATR chassis with VMEbus tracking and
wirewrap spills on user-defined pins. These pins can be
wired to a series of connectors and then cabled to the
chassis’ front panel connectors.
In designing the production system, however, Radstone
implemented other innovative techniques, drawing on its
experience and expertise in designing PCBs that use
some of the world’s most advanced construction
materials and practices, combined with an imaginative
approach to wiring to the front panel.
Essentially the two developments are:
• the integration of all I/O wiring into the tracking of the
backplane itself as opposed to wire-wrap
• ‘translating’ the complex cable harnesses from the
backplane to the front panel into easy-to-assemble
flexible interconnects known as flex-circuits.
To achieve tracking in the backplane itself, Radstone
added seven additional electrical tracking layers to a
standard PCB backplane which comprises 12 layers.
Conventional approaches carrying these signals as a
mesh of complex cables, each configured to reflect the
nature of the signal – in terms of, for example, a twisted
pair compared to a screen twisted pair – and which cater
for specific interfaces which might have controlled
impedances.
Typically, the time taken to manually wire a chassis took
six weeks – Radstone’s new approach slashed that time
down to two days.
Using advanced CAD tools, Radstone’s engineers
recreated the wiring as circuits which were translated
within the seven tracking layers of the backplane. The
characteristics of the different cable types were reflected
in the design. For example, twisted pair cable was
simulated by parallel traces, and screening by guard
traces, connected to digital ground above and below the
signals.
For the connection from the backplane to the front panel
Radstone again offered an innovative solution through the
use of flexible circuits which could be easily attached to
either end of the PCB.
“But while the use of flex-circuits has saved a lot of
time,” observes Kaval, “the most important thing for me is
that it reduces the risk of wrongly routed circuits or short
circuits. Translating most of the wiring into the tracking
dramatically reduces any scope for human error, as well
as streamlining the assembly process.”
Future developments have again been designed-in, with
the tracking for a 1553 interface already included which
will enable PMADS to interface to digital launchers when
required.
Completing this part of the system is the chassis’ front
panel, for which a bespoke configuration of connectors
was designed to meet Aselsan’s particular needs which
included the use of gaskets in case the chassis is subject
to ‘hose down’ in the field.
Radstone’s attention to detail went as far as ensuring that
there was sufficient space around connectors to enable
easy connections by gloved hands.
Thermal Analysis and System Testing
Radstone’s approach to thermal management starts with
component selection and placing. Critically, the company
designs its own boards which represent the leading edge
of PCB technology with micro-vias, laser imaging and
new laminate materials harnessed to improve thermal
conductivity and provide enhanced stiffness to reduce the
harmful effects of vibration. But while Aselsan’s system
benefits from being air-cooled via an avionics-class fan
drawing air over the surface of the boards and out of the
chassis, leaving nothing to chance Radstone undertook a
full thermal analysis using Flomerics’ FLOTHERM.
As board level configurations were defined, Radstone
performed a full system level thermal analysis to validate
that, in theory at least, using standard Level 4 boards (-40
deg C to +75 deg C) would meet the required operating
temperature range for the equipment. This theoretical analysis was later backed up by measurements made on individual production
units, including putting the entire production system successfully through full
type approval testing, including full Environmental Stress Screen (ESS) and
temperature cycling and random vibration testing.
As with all Radstone systems, testing does not end with successful
qualification. For each of its products the company writes a set of test
paradigms that deliver built-in-test (BIT) firmware to assure confidence in the
operation of equipment at power up, and also a BCS (Background Condition
Screening) toolset that goes beyond the field capabilities of BIT to provide
continuous test routines during actual deployment – with no loss of
performance.
The Importance of Teamwork
Kaval’s experience of working with Radstone has been so positive that he has
recommended the company to other parts of Aselsan, and importantly, the
success of PMADS has seen a prototype of a naval variant – the BORA – enter
field trials.
While Kaval is the first to acknowledge the technical innovation and
leadership Radstone has demonstrated, asked for what he feels has been
Radstone’s most significant contribution his response is ‘teamwork’.
“Radstone’s technology is impressive, but so too are their people. Our
engineers have built up very good working relationships with their engineers
and there have been several visits by each group of engineers to the other.
They are,” Kaval says simply, “compatible.”
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