MOSFET

What is the sign of the threshold voltage (relative to the source) of an enhancement-mode p-channel MOSFET?

  1. APositive
  2. BNegative
  3. CAlways 0 V
Show answer and explanation

Answer: B. Negative

A p-channel MOSFET turns on when a gate voltage lower (more negative) than the source forms a hole inversion layer at the surface of the n-type substrate. The threshold voltage of an enhancement-mode pMOS is therefore negative.

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