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Design >> High-Power Design >> some questions about Type 3 Compensation for dc-dc
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Message started by waseda-rfic on Oct 17^th, 2010, 5:51am

Title: some questions about Type 3 Compensation for dc-dc
Post by waseda-rfic on Oct 17^th, 2010, 5:51am

the Type 3 Conventional Operational Amplifier Compensation introduce 3 poles and 2 two zreos. it uses 2 pole to Compensate two zeros in dc-dc and uses 2 zeros to Compensate poles in dc-dc .
I want to ask two questions:
1. when design the Compensation circuit , the operational amplifier has its own poles and zeros besides the 3 poles and 2 two zreos, how to do with the poles and zeros of the operational amplifier.
2. there are two pole-at-zero when the dc-dc is Compensated. the pole-at-zeros have bad effect on transient response of the loop. whether the two pole-at-zero have bad effect on transient response of the loop.?

Title: Re: some questions about Type 3 Compensation for dc-dc
Post by raja.cedt on Oct 21^st, 2010, 2:54am

hi,
whatever be the poles and zero location of your op-amp if they are well beyond UGB then fine.

Thanks.

Title: Re: some questions about Type 3 Compensation for dc-dc
Post by waseda-rfic on Nov 1^st, 2010, 6:35pm

raja.cedt wrote on Oct 21^st, 2010, 2:54am:

hi,
whatever be the poles and zero location of your op-amp if they are well beyond UGB then fine.

Thanks.

Thanks! but the main pole of the OPA is usually several hundred Hz, so it is hard to beyond the poles and zero location I need in the dc-dc

Title: Re: some questions about Type 3 Compensation for dc-dc
Post by Alexandar on Dec 7^th, 2010, 11:54pm

from a quick google-search this pops up:
http://designtools.analog.com/dt/stability/stability.html