Enhancement Mode Mosfets - Peak Atlas DCA75 Pro User Manual

Peak Atlas DCA Pro User Guide June 2019 – Rev 1.7

Enhancement Mode MOSFETs

MOSFET stands for Metal Oxide Semiconductor Field Effect
Transistor. They are available in two main types, N-Channel
and P-Channel. Most modern MOSFETs are of the
Enhancement Mode type, meaning that the bias of the gate-source voltage is
always positive (For N-Channel types). The other (rarer) type of MOSFET is
the Depletion Mode type which is described in a later section.
MOSFETs of all types have an insulated gate which results in negligible gate
current for both positive and negative gate-source voltages (up to the maximum
allowed values of course, typically ±8V to ±20V).
The first screen to be displayed gives
information on the type of MOSFET
detected and the pinout.
Pressing scroll-off will then result in
the gate threshold and other parameters
of the MOSFET to be displayed.
The (on) gate threshold voltage is the
gate-source voltage at which conduction
between the source and drain starts. The
DCA Pro determines that drain-source
conduction has started when it reaches a
current of 5.00mA, this is confirmed on
the display.
An enhancement MOSFET will typically be "off" when the gate-source
voltage is 0V.
The DCA Pro can drive the gate from 0V to 8V for enhancement mode
MOSFETs.
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