As the reverse-bias potential increases, the width of the depletion region increases,
which in turn reduces the transition capacitance. The characteristics of a typical commercially
available varicap diode appear in Fig. 16.7 . Note the initial sharp decline in C T with
increase in reverse bias. The normal range of V R for VVC diodes is limited to about 20 V.
In terms of the applied reverse bias, the transition capacitance is given approximately by