Preparing for a VLSI interview:

Here are my tips on students appearing for interviews for VLSI design jobs.
I am not going to bore you by putting obvious HR type tips here. These
are specific to a VLSI job interview, and will surely help.

I do have a very comprehensive set of technical questions which is available Here.
My experience says, that if you are capable to understand and answer even 50%
of these questions, chances are you wont fail a VLSI interview as a fresh
graduate(PG or UG) I also sort of guarantee that some of the questions
will appear as is, in your interview.
But then just knowing answers wont help, you must be able to solve them
yourself, and must gain enough confidence, that you can solve these kind of
questions rather that specifically these questions.

This section is however dedicated to preparation of interview apart from
preparing questions.

If you are new to UK or have never been to a UK interview, I guess it will
be a good information that, the UK interviews are very cool. But that doesn't mean
that they are easy. Cool means, that you will find interviewers taking more than
you, sort of trying to market the job to you, making the interview process light and
I know at times in India ppl have found in an interview that the interviewer, instead
of testing your knowledge, tells you how much knowledgeable he/she is. Here
it wont be like that(hopefully :)

0). Making an application:
When applying for a job, read thoroughly, the job as described. Then make a
cover letter, possibly briefly explaining why you are fit for this job. For example
indicating that your project/thesis matches with the job description, or your
interest(s) match with the job description.
Do not just attach your CV and send without a cover letter. It may indicate your lack of sincerity
towards the job/company. Take is as an opportunity to sell yourself, but do
not make it lengthy so that the reader gets bored of reading. a 1/4 page to 1/2 page cover
letter is generally cool.
If required, tailor your CV a bit to match the job description. but ONLY a bit.
If you need to do more than 'bit', the job probably isn't for you.

You may want to have a look of a list of companies in UK offering a job in VLSI.
It may help you in selecting a company or a job you wish to apply for. Do apply for
jobs which requires 1-2 years of experience, even though you are a fresh graduate,
briefly explainging why you think you may be able to handle it.
Unfortunately, a very few of them need fresher(s). I Dont understand how are they
going to get experienced after 3-4 years from now if they do not take freshers on
board now, nevertheless, the plus here is: It is relatively eaiser for a fresh graduate
to crack interview as compared to a experienced person, after having received a
face-to-face interview call.

1). Your CV.
Your CV should be clear and not too elaborated. For a recent student a 2 page
CV is supposed to be enough. Clearly give your contact details and your
UK work permit status.
Most important technical info on your CV will be your Project/MSc Thesis.
Highlight or use 'bold' font for your skill key words, such as VHDL, verilog, Synthesis,
CMOS design, Unix/Perl/C, Matlab, DSP, DFT etc

Design your CV so that if your CV has been short listed, and you have been
called, then you can sort of proof to them that you are the person which
matches the CV. That means no exaggeration of what you have done,
No lies, and as much accurate as possible.
Its not much, that is expected from a fresher, so keep it simple.
DO NOT use any word in the CV which you cannot explain or which
you do not have knowledge about.
Generally speaking when a CV is selected, then the only thing which is
expected in a face-to-face interview is that the person should match the CV.

2). Master one field/domain.
Choose any one field/domain, and master yourself to that. Say for example
someone can master 'Digital Design', others may choose CMOS circuit design.
You may want to hint your strong points in your CV say for example in
'interests' section of your CV. Try to find as many questions as possible in
the chosen field, and try to solve them yourself.
Understand your chosen field thoroughly.
My first interview was at STMicroelctronics, and I mastered Digital Electronics.
I was asked to do a state machine design, which I successfully did.
I answered correctly(well thatís what I believe) about 60% of the questions asked, and I got the job.

3. Answering Questions:
Analyse the question in your mind, and understand what is being asked. If the question is
not clear, your answer will be wrong. You may ask the question again politely, if you think it may
help you to understand the question.
Try to think of a solution, and feel free to say "Please can I have a couple of minutes to think"?
Also you may request for hints if you think it may help. Generally speaking, the interviewer will
give hints, and will try to push your brain to work, up until the point when your brain clicks. Your
direction of thinking and approach is the key, even if you fail to answer.
And if you haven't got a clue, do not be ashamed in saying "sorry". But do not attempt to
answer if you know that you do not know the answer.
An Example:
Interviewer Asks: Can you tell me what is the max frequency a digital circuit may work?
In case you are unable to answer, he may offer hints like:
Do you know what is setup time or propagation delay? etc.
Then he may actually draw a circuit, and mark propagation delays, setup times etc.. to
again make you think towards the answer.
So even if you do not know the answer, try to think on the spot using hints and direction given.
Again, your approach and direction is very important.
Remeber, they are interviewing to select you and not to reject you.

4. General information about the company:
You MUST have a look at the companies website and have a good understanding of their
products. Try to think how your interests may coincide with the business of the company.

5. Your final year project or masters thesis:
Probably the most improtant thing in your CV would be your project work or masters thesis.
Prepare it very thoroughly. I can almost guarantee that you will be asked about it. You must
prepare in advance, try to think of questions which may be asked, and be prepared to make
use of a drawing board to explain what you have done.
I know examples of interviews where the whole interview went around the project/thesis.

If you are able to engage them for about 1/2 + hour or so on your project, there is hardly
any time left for them to quiz you on other things. So it is an opportunity to tell the interviwers
what to ask, make full use of it.

You must be prepared to postitively criticize your own work.
For example:
I did my masters project as 'Motion estimation block for MPEG-4 Encoder'.
I successfully positively criticized my work by admitting that the algorithm used wasn't the
best that could have been implemented, but given the time frame, and the importance of
producing a 'working' project, I had to compromise on going too much on algorithm
evaluation and development.
If you are a student reading this page just for information, and you
havn't done your project/thesis yet, then please remember it is the MOST imp part of your
degree which can help you in getting a job, so please do it giving your heart and soul. If it
is a group project, then make sure that you know as much as you can, apart from your

6). Flexibility:
Show flexibility in your choices, and in your eagerness to take up challenges in a varity
of work. You may say that your interests lies in a pool of domains, which are closely related.

While showing a bit of flexibility is a good idea, do not be over flexible, such as switching
your interests from Digital to Analog on the name of flexibility.

 Most frequently asked questions in a VLSI interview to fresher(s):
1). What is setup/hold times. their significance in calculating frequency at which a circuit may work at
2). State Machines: Draw a state machine to detect say a pattern of "01110" in a serial stream. Detect
both, overlapping and non-overlapping
3). Gray counters? where they are used?
4). Frequency domain crossing.
5). One hot vs state encoded state machines? Advantages of one over the other.
6). Make a T-FF using a D-FF
7). Sync counters and A-Sync Counters
8). What are LFSR(s).
9). Difference between VHDL 'variable' and 'Signal'. Where they are specifically used.
10). Sensitivity lists in VHDL/Verilog and its importance
11). Un-intentional Latch inference in VHDL/Verilog Synthesis, its causes and cure.
12). What technology is the industry working at currently.
13). Low Power Design Techniques for Digital design.
14). Difference between a latch and an FF
15). Latch-up, causes and cure
16). Difference between verilog blocking and non-blocking assignments.
17). Noise margin
18). A deisgn has a small timing violation, suggest what may be done?
19). Why CMOS, why not TTL or any other logic family?
20). Why is technology shrinking? What are the benefits and challanges?

7. If you are a PG student: you MUST understand very clearly what is meant by the following terms
RTL, Simulaiton, Symthesis, Back-Annotation, netlist, Technology Library, Static Timing Analysis, PnR,
Physcial Design, Clock Tree, Layout, DRC/LVS, cross talk, code coverage, formal verification and
its importance, clock gating, duty cycle, dynamic power,static power, leakage current, hardware accelerators,
cycle based simulation, and event based simulation, difference between the two and their advantages
over the other, Placement driven synthesis, timing closure, clock skew, signal integrity, clock jitter.

8. Rest are HR type questions: which any web site will tell you , and I will sure not put them

Last but may be most important: Your confidence matters a LOT, and confidence can only
be attained by hard work and deep understanding.

koi shak ya sawal?
avimit at yahoo dat com