Home » ECE VIVA Questions » 20 TOP VLSI LAB VIVA Questions and Answers 20 TOP VLSI LAB VIVA Questions and Answers Posted on August 19, 2018June 28, 2017 by engineer1 Comment VLSI viva Questions and Answers :- 1. Why does the present VLSI circuits use MOSFETs instead of BJTs? 2. What are the various regions of operation of MOSFET? How are those regions used? 3. What is threshold voltage? 4. What does it mean “the channel is pinched off”? 5. Explain the three regions of operation of a MOSFET. 6. What is channel-length modulation? 7. Explain depletion region. 8. What is body effect? 9. Give various factors on which threshold voltage depends. 10. In a system with insufficient hold time, will slowing down the clock frequency help? VLSI VIVA Questions and Answers : 11) Mention what are three regions of operation of MOSFET and how are they used? 12) Explain what is the depletion region? 13) Explain why is the number of gate inputs to CMOS gates usually limited to four? 14) Explain what is multiplexer? 15) Explain what is SCR (Silicon Controlled Rectifier)? 16) Explain what is Slack? 17) Explain what is the use of defpararm? 18) Explain how logical gates are controlled by Boolean logic? 19) Mention what are the different gates where Boolean logic are applicable? 20) Explain how binary number can give a signal or convert into a digital signal?