# Logic design engineer Interview Questions

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Logic Design Engineer interview questions shared by candidates### You have a 4bit binary number. You wish to multiply it with decimal 24 using only combinational logic, with minimal adders.

2 Answers↳

one could store 2^4=16 lines of already made solutions in mem and get them in O(1) Less

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24 decimal could be represented by: 16 + 8. Power of 2 multiplication could be done by shifting left. Therfore, we have: 24*X = 16*X + 8*X = X & "0000" + X & "000". In this solution we used one adder. Less

### Could you name different kinds of flip-flops?

2 Answers↳

D flip-flops, T flip-flops, JK flip-flops.

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SR flip flop,D-flip flop,JK flip flop,T flip flop,master slave flip flop

### Question about verilog function and task, the functionality and difference

1 Answers↳

Since I am not familiar with verilog function and task

### the elements of leakage current and how u reduce each element

1 Answers↳

with current technologies for better performance there is decreased in threshold voltage which increase leakage current flowing through various parts of transistor like subthreshold current through channel and these are increasing worth low power applications as transistor size shrinks Less

### Lots of questions were asked & was made to solve many problems based on 3 subjects above. They were more interested in your knowledge than whatever u have written in cv.

1 Answers↳

good

### Do we need PC to index second level table of branch predictor (i.e. pattern history table)? Why? What if bits of PC more than bits to index to pattern history table?

1 Answers↳

Yes. Different branches may have same history but different prediction. Fold PC, i.e. xor higher bits of PC with lower bits of PC. Less