
Pin Diodes 303
1
"/~'///////////~
IV +
p+
"/////~r//~,
Figure 15-8
PIN
diode structure.
period for recombination.
Because of this delay phenomenon, there is always a small
but finite number of carriers in the I region that are uncombined. As a result, the
resistivity of the I region is very low.
Radio-frequency ac signals can pass through the
PIN
device and, in fact,
under some circumstances see it as merely a parallel plate capacitor. We can use
PIN
diodes as electronic switches for RF signals and as an RF delay line or phase
shifter, or as an amplitude modulator.
15-6.1
PIN
Diode Switch Circuits
PIN
diodes can be used ...