AdvancedA-002-004-002
What is a depletion-mode FET?
A
Answer
Circuit design and power supplies
Type
A
An FET that has a channel with no gate voltage applied a current flows with zero gate voltage
B
An FET without a channel to hinder current through the gate
C
An FET that has a channel that blocks current when the gate voltage is zero
D
An FET without a channel no current flows with zero gate voltage
Answer Notes
A depletion-mode Field Effect Transistor (FET) is a "normally on" device. This means a physical channel for charge carriers already exists between the source and the drain, allowing current to flow freely even when the gate voltage is at zero.
To stop or reduce the current flow in this type of transistor, a specific gate voltage must be applied to "deplete" the channel of charge carriers, effectively pinching off the current.
This behavior is the exact opposite of an enhancement-mode FET, which is normally off. Distractors describing devices without a channel or those that block current at zero voltage are actually describing enhancement-mode devices.
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What is an enhancement-mode FET?
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