The specific gate voltage in a JFET that drives the drain current to zero is designated as the ______________ voltage?
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Answer: B. pinch-off
Explanation
The pinch off voltage specifically reduces the conducting channel width to zero current. Applying this gate voltage shuts off the flow of carriers through the device channel. This particular operating condition distinguishes the active region from the complete cutoff state. A junction field effect transistor operates by modulating a semiconductor channel via depletion regions. The gate terminal forms a reverse biased pn junction with the underlying channel material. Increasing reverse bias expands the depletion region and constricts the available pathway for electrons.
Circuit designers rely on this parameter to determine maximum voltage limits for switching applications. Understanding pinch off ensures proper biasing in analog amplifier designs without signal distortion. This characteristic limits power dissipation and prevents thermal runaway in discrete transistor circuits. Saturation refers to the region where drain current remains constant despite voltage changes. The active region describes normal linear operation rather than the complete cessation of current. Cut off is a broader term, whereas pinch off specifically defines the channel closing condition.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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