Appendix B. Feedback Loop
Compensation
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The heart of every linear and switching power supply is a negative feedback loop
which maintains a constant value for the output voltage(s). To accomplish this,
an error amplifier is used, which attempts to minimize the error between the
output voltage and an ideal reference voltage. If the world were well behaved,
a very high-gain inverting amplifier would be used and this job would be simple.
The reality is that loads change, and the input voltage suddenly goes up or
down. The error amplifier must respond to these changes quickly and without
oscillating. This is complicated because the response in the power portion ...