Class-D amplifiers use pulse width modulation (PWM) to sample the audio signal.
With the use of a half-bridge or full-bridge design it amplifies the sampled pulse
train wave. The choice of sampling frequency is very critical to have an accurate
representation of the sampled audio signal. The audible audio signal frequency is
from 20 Hz to 20 kHz. Knowing this we have to choose a sample frequency that is at
least twice that of the audio signal due to the Nyquist Theorem. For low distortion a
factor of 5 to 50 times greater is used but due to chosen components the sampling
frequency was chosen to be 200 kHz. One thing to keep in mind is that as the
frequency is increased so are the losses in the MOSFET’s, due to their gate