100

1k

10k

100k

1M

10M

0

5

10

15

20

25

30

35

40

FREQUENCY (Hz)

-ADJ

-5.0

LM22678

www.ti.com

SNVS585K – SEPTEMBER 2008 – REVISED MARCH 2013

Alternatively, this pole should be placed between 1.5kHz and 15kHz and is given by the equation shown below:

(9)

The Q factor depends on the parasitic resistance of the power stage components and is not typically in the

control of the designer. Of course, loop compensation is only one consideration when selecting power stage

components; see Application Information for more details.

Figure 14. Compensator Gain

In general, hand calculations or simulations can only aid in selecting good power stage components. Good

design practice dictates that load and line transient testing should be done to verify the stability of the application.

Also, Bode plot measurements should be made to determine stability margins. Application note AN-1889

SNVA364shows how to perform a loop transfer function measurement with only an oscilloscope and function

generator.

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