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VLSI Interview Questions with Answers - 1

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. Give the Cross-sectional diagram of the CMOS.


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Digital Design Interview Questions - All in 1

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Gate-Level Modeling

>> Introduction
>> Gate Primitives
>> Delays
>> Examples


In Verilog HDL a module can be defined using various levels of abstraction. There are four levels of abstraction in verilog. They are:
Behavioral or algorithmic level: This is the highest level of abstraction. A module can be implemented in terms of the design algorithm. The designer no need to have any knowledge of hardware implementation.Data flow level: In this level the module is designed by specifying the data flow. Designer must how data flows between various registers of the design.Gate level: The module is implemented in terms of logic gates and interconnections between these gates. Designer should know the gate-level diagram of the design.Switch level: This is the lowest level of abstraction. The design is implemented using switches/transistors. Designer requires the knowledge of switch-level implementation details.
Gate-level modeling is virtually the lowest-level of abstraction, because t…