L) Mosfets - VOLTCRAFT TT100 Bedienungsanleitung

l) MOSFETs

MOSFET stands for metal oxide semi-
conductor field effect transistor. As bipo-
lar transistors, MOSFETs are also avail-
able in two principal designs, N-channel
and P-channel. Most modern MOSFETs
are self-protected MOSFETs, i.e. the
gate-source voltage is always positive
(for N channel types). The other (rare)
type of MOSFET is the self-conducting
MOSFET, which is described in a later
section.
MOSFETs of all kinds are sometimes referred to as IGFETs,
insulated-gate field-effect transistors. This term describes a fun-
damental feature of these components, an insulated gate, which
leads to a negligible gate current for both positive as well as nega-
tive gate voltages (of course up to the maximum permitted values,
typically ± 20V).
The first screen that is displayed shows
information on the type of MOSFET de-
tected. Pressing the OFF/Page button
changes the display to the MOSFET
pinout. The gate, source and drain are
each identified.
An important characteristic of a MOS-
FET is the gate-source threshold volt-
age, the gate-source voltage at which
the leakage between the source and
drain begins. The gate threshold value
is displayed after the pinout.
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