MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages:

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Multiple Choice

MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages:

The gate of a MOSFET is a very thin insulator, so it can be damaged by static charges or voltage spikes that push the gate-to-source voltage beyond the oxide’s safe limit. A built-in protective device between the gate and source acts as a clamp, keeping Vgs within a safe range. A Zener diode is ideal for this role because it normally does nothing during normal operation, but when the gate voltage tries to rise too high, the Zener breaks down at a defined voltage and conducts, shunting the excess current to the source. This keeps the transistor from breaking down the gate oxide while allowing normal gate drive to proceed. Other devices wouldn’t serve this purpose as cleanly. A Schottky diode would clamp at a very low forward voltage and interfere with normal gate voltages. A metal oxide varistor is designed for larger, external surge protection and isn’t integrated into the gate circuit. A tunnel diode isn’t used for gate protection.

The gate of a MOSFET is a very thin insulator, so it can be damaged by static charges or voltage spikes that push the gate-to-source voltage beyond the oxide’s safe limit. A built-in protective device between the gate and source acts as a clamp, keeping Vgs within a safe range. A Zener diode is ideal for this role because it normally does nothing during normal operation, but when the gate voltage tries to rise too high, the Zener breaks down at a defined voltage and conducts, shunting the excess current to the source. This keeps the transistor from breaking down the gate oxide while allowing normal gate drive to proceed.

Other devices wouldn’t serve this purpose as cleanly. A Schottky diode would clamp at a very low forward voltage and interfere with normal gate voltages. A metal oxide varistor is designed for larger, external surge protection and isn’t integrated into the gate circuit. A tunnel diode isn’t used for gate protection.

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