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VLSI Interview Questions - 4

1. Why is the number of gate inputs to CMOS gates (e.g. NAND or NOR gates)usually limited to four?
Answer

2. What are static and dynamic power dissipation w.r.t to CMOS gate?
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3. Draw Vds-Ids curve for a MOSFET. Now, show how this curve changes (a) with increasing Vgs (b) considering Channel Length Modulation.
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4. Which is fastest among the following technologies: CMOS, BiCMOS, TTL, ECL?
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5. What is a transmission gate, and what is its typical use in VLSI?
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6. Draw the cross section of nMOS or pMOS.
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7. What should be done to the size of a pMOS transistor inorder to increase its threshold voltage?
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8. Explain the various MOSFET Capacitances and their significance.
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9. On what factors does the resistance of metal depend on?
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10. Draw the layout a CMOS NAND gate.
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