EC 255 VLSI DESIGN

QUESTION BANK

UNIT IV

1 Mark

1. Use pass transistors to implement Vout = A.B.C.D

2. What is gate restoring logic

3. Data selector is the other name for ------------------------------

4. Draw the circuit for 2 phase clocking

5. mention the advantages and disadvantages of Domino logic

6. What are non overlapping clocks?

7. What is gate logic?

8. What is switch logic

9. Draw the basic structure of CMOS Domino logic

10. What is inverter logic

11. Draw the structure of dynamic register element using nmos pass transistor

12. Draw the structure of dynamic register element using cmos transmission gate

13. Other name of NORA logic

14. Write the logical expression for a 4 way mux

15. Write the functional expression of 1 bit parity cell.

2 Marks

1. What is charge sharing?

2. Draw the circuit for simple 2 phase clock generator

3. Structure of 4 bit dynamic shift register with CMOS logic.

4. switch logic implementation of 4 way MUX

5. Draw the structure of 2 input NOR gate in BiCMOS logic

6. Draw the output waveform of two phase clocking

7. Draw the switch logic implementation of 4 way mux

8. Draw the structure of clocked cmos inverter

9. Mention the disadvantages of dynamic logic circuits

10. Differentiate pass transistor and transmission gates

6 or 7 Marks

1. Write the working of dynamic shift register element

2. What are the steps required for proper design of larger systems in VLSI

3. Describe the working of Pseudo nmos NAND gate

4. With a neat diagram explain the working of NP DOMINO logic

5. With a neat diagram explain the working of C2 MOS logic

6. With relevant waveforms and circuit explain the working of any 2 phase clock

generator

7. Write short notes on charge storage

8. With neat examples explain pass transistor and transmission gate

9. Implement OR and AND operations in switch logic representation and explain the

same

10. Write short notes on switch logic and gate restoration logic circuits

10 Marks

1. Briefly explain the working, advantages and disadvantages of dynamic logic.

2. Briefly explain the working, advantages and disadvantages of domino logic.

3. With a neat diagram explain the working of

a) NP DOMINO logic

b) C2 MOS logic

4. Design a one bit parity generator and explain its working. Draw the equivalent stick

diagram using nmos

5. Explain the working of 4 way data multiplexer in its switch logic implementation.

6. Design a one bit parity generator and explain its working. Draw the equivalent stick

diagram using cmos

7. With relevant waveforms and circuits explain the working of all 2 phase clock

generator

8. Draw the circuit and explain the working of nmos 4 bit dynamic shift register

9. Draw the circuit and explain the working of cmos 4 bit dynamic shift register

10. Explain the working any three logic structures with relevant diagrams and mention

their advantages over other logic structures