Explain the various MOSFET Capacitances & their
significance?
Answer / arpit raj
There are different MOSFET capacitance they are as follows:
1) Cgs : it is the capacitance due to the overlap of the
source and the channel regions by the polsilicon gate and is
independent of applied voltage.
2) Cgd : it consists of 2 parts, first is the capacitance
associated with the overlap of the polysilicon gate and the
silicon below. second is the capacitance associated with the
depletion region immediately under the gate. Cgd is
nonlinear function of voltage.
3) Cds : it is the capacitance associated with the
body-drift diode. it varies inversely with the square root
of drain-source bias.
Significance:
input capacitance : Ciss = Cgs + Cgd, Cds shorted
output capacitance : Coss = Cgd
reverse transfer capacitance : Crss = Cds + Cgd
Cgd provides feedback loop between the output and the input
of the circuit, also called Miller capacitance.
other capacitance are responsible for charging and
discharging , or for switcing purposes
Is This Answer Correct ? | 37 Yes | 15 No |
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