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Lateral depletion-mode DMOS FETs
7.7 Lateral depletion-mode DMOS FETs
Changing the DMOS FET’s geometry and processing can help enhance or exploit
other features, such as switching speed. Although more difficult to manufacture, and
the least available member of the FET family, the high-speed, low-voltage, lateral
depletion-mode DMOS FET (LDMOS) features low distortion, a wide dynamic range,
and ultra-high-frequency operation with turn-on speeds of less than 1 nS. This device
can be considered a bridge between high-speed JFETs and gallium-arsenide (GaAs)
FETs. The device’s main advantage is the very low capacitance (less than 10 pF),
which makes it eminently ...