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VLSI Interview Questions - 6

1. Why is NAND gate preferred over NOR gate for fabrication?
Answer

2. Which transistor has higher gain: BJT or MOSFET and why?
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3. Why PMOS and NMOS are sized equally in a transmission gates?
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4. What is SCR?
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5. In CMOS digital design, why is the size of PMOS is generally higher than that of the NMOS?
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6. What is slack?
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7. What is latch up?
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8. Why is the size of inverters in buffer design gradually increased? Why not give the output of a circuit to one large inverter?
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9. What is Charge Sharing? Explain the Charge Sharing problem while sampling data from a Bus?
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10. What happens to delay if load capacitance is increased?
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