The Maplin Electronic Circuits Handbook, 2nd Edition

248

PROJECTS

MOSFET power amplifier

Power MOSFETs

are a

relatively

new

addition

to the

range

of

semiconductor devices available. Such devices offer

a

number

of

significant advantages when compared with conventional bipolar trans-

sistors including excellent high frequency response

and

inherent

immunity from thermal runaway. Power MOSFETs

are

thus

a

natural

choice

for any

high performance output stage.

Figure 11.12 shows

the

symbols

of

N-channel

and

P-channel MOSFET

devices. Such devices

can be

used

in

complementary output configura-

tions like those shown

in

Figure 4.38.

A

typical output characteristic

for

a power MOSFET

is

shown

in

Figure

11.13 ...