If the output capacitor is of high ESR (0.1

Ω or higher), it may

be necessary to use C

A rule of thumb is that if

1/(2

πC

used. Choose C

(R

where R

Improving Transient Response Time

The above compensator design provides a loop gain with

high phase margin for a large stability margin. The transient

response time of this loop is limited by the lower

mid-frequency gain necessary to achieve a high phase mar-

gin. If it is desired to increase the transient response time,

C

will yield increasingly shorter transient response times, how-

ever the loop phase margin will become progressively lower

as C

transient response time, it is recommended to keep the

phase margin above 40˚.

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