Digital Design Interview Questions - 4

1. Design 2 input AND, OR, and EXOR gates using 2 input NAND gate.




2. Design a circuit which doubles the frequency of a given input clock signal.




3. Implement a D-latch using 2x1 multiplexer(s).




4. Give the excitation table of a JK flip-flop.




5. Give the Binary, Hexadecimal, BCD, and Excess-3 code for decimal 14.


14:
Binary: 1110
Hexadecimal: E
BCD: 0001 0100
Excess-3: 10001

6. What is race condition?




7. Give 1's and 2's complement of 19.


19: 10011
1's complement: 01100
2's complement: 01101

8. Design a 3:6 decoder.




9. If A*B=C and C*A=B then, what is the Boolean operator * ?


* is Exclusive-OR.

10. Design a 3 bit Gray Counter.



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