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Type-1: Design a ...

Most Common Interview Questions: Type-1: Design a ...

This is the most common question one will face in his/her interview, probably the first question which starts testing your knowledge. (I mean this comes after introduction and "Tell us about yourself"). This is a lethal weapon used by the interviewer to test one's abilities: both weak and strong points. The concepts required for solving the problem are generally related to the type of job you are being tested for.

The most popular strategy used by the interview in this question is gradual increase in the complexity of the question. It goes like this ... Interviewer states the specifications of the design. You can present as simple/straight forward/redundant answer as possible. The next question could be redesign using only NOR gates or NAND gates. Followed by "what are minimum number of NAND gates required for this particular design" and it goes on.

Sometimes it starts with designing a small block. Then you will be asked to embed this module in a bigger picture and analyze the scenario. Where most likely you will face questions like "can the design (you made) be optimized for better performance of the entire module?" or "what drawbacks you see in your design when embedded in the bigger module". Basically tests how good you are with designs with a hierarchy.

Another way is step by step removal of assumptions that make the design complex as we go further.

Tips
  • Read the job description, think of possible questions or target areas, and prepare for the same.
  • ASIC interviews (especially freshers) expect a question dealing timing analysis, synthesis related issues, etc.
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