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Help me,poles and zero analysis in bipolar LDO IC

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qwertyIC

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In the present,I have confused with the problem.Generally,how many poles and zero in LDO IC with bipolar process? which is the dominant pole? and which part do each of them come from? Are they diffrent from with CMOS LDO?thanks very much! Below picture show the block of LDO
 

isn't it better to attach that pic as jpg file instead of pdf?
 

This is first time for me to write in the forum and I didn't succeed in pasting pic.
I am sorry and I try again.
 

I am also interesting.
57_1166006860.GIF
 

I'd say that the poles can be divided into two groups:

-Poles in the opamp: Miller pole and mirror pole (that should be the non-dominant one)
-poles of the LDO: there are those cause by the opamp, the loading of the pass device on the opamp will create another pole, and output capacitance (C0) will add another pole as well.
 

It may like this (I cannot make sure in 100%):

The dominate pole may be the pole in the filter [1/(2 pi RL Co)], or poles in Iout/Vop.
For the zero, esr RHP zero may be the most low frequency zero.

Added after 2 minutes:


96_1166033669.gif
 

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