# NAND2 CMOS help

Discussion in 'Homework Help' started by geft, Dec 26, 2011.

1. ### geft Thread Starter New Member

Dec 8, 2011
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The question asks to find the threshold voltage for the case where two inputs switch simultaneously. What does this mean?

2. ### praondevou AAC Fanatic!

Jul 9, 2011
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Please post the context, maybe the original question with a picture or formula or something.

3. ### geft Thread Starter New Member

Dec 8, 2011
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Consider a CMOS NAND2 gate for the case where the two inputs switch simultaneously.
Assume $k_p = k_n = 100 uA/V^2$. Derive an expression for $V_{th}$.

It then notes that when both transistors are switching simultaneously, NMOSA is in saturation and NMOSB is in linear region.

What does "two inputs switch simultaneously" mean?

Last edited: Dec 26, 2011
4. ### MrChips Moderator

Oct 2, 2009
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You cannot get much clearer than that. It means both inputs are changing at the same time.

5. ### geft Thread Starter New Member

Dec 8, 2011
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Would that affect the circuit differently compared to when the inputs are both static?

Oct 2, 2009
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