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gain boost folded cascade opamp vs folded cascade opamp

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sissi

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gain boost

what is spec changed? e.g. Gain boost folded cascade opamp gain increases (1+A), A is the additional op amp.how about SR ,UGB, PM?

Added after 16 minutes:

urgent

Added after 26 minutes:

somebody can offer me some literature about the gain boost folded cascade opamp?
 

gain boosting opamp

Hi
Folded cascode has one dominant pole. (single pole)
So gain boosted folded cascade is single pole agian if you design booster correctly. (see bult's paper)
so, SR, UGB and PM stays almost constant.
regards
 

cascode zero gain boosting

hi,who decides PM?I want to know.
 

cascading opamps

Hi
single pole amp has 90 PM.
but pole-zero doublet can destroy PM and UGB.
regards
 

folded cascade

hi
but some paper said nondominant decides and influentes the PM.
"Design Procedures for a Fully Differential Folded-Cascode CMOSOperational Amplifier" SUDHIR M. MALLYA, MEMRER,IEEE,AND
JOSEPH H. NEVIN, MEMBER,IEEE

Added after 59 minutes:

"Design Procedures for a Fully Differential Folded-Cascode CMOSOperational Amplifier" SUDHIR M. MALLYA, MEMRER,IEEE,AND
JOSEPH H. NEVIN, MEMBER,IEEE
 
available op amp in iran

Hi
yes it is true.
All of my opinions are true if you have a large capacitive load.
yes Cl1 can effect PM but if Cl is large enough there is no problem.
as you can see in table IV.
regards
 

gain boosting

hi
i see.thank you
 

cascade op amp

The gain-boosting opamp have a doublet located in the GBW of the auxilary opamp,which may affect the settling time badly.you can learn more about it in K. Bult and G. Geelen. 's article.
 

gain boosted cascode

You need to be careful while designing the auxiliary amplifier
as this when put into the system introduces a pole zero doublet
which may not necessarily visible in the frequency plot and hence
do not degrade the phase margin but you need to simulate the circuit in
time domain to see the actual stability.

A paper by Klass Bult on Gain Boosting is available at

This discusses on the effect of pole zero doublet and gives an intuitive
relation between the UGF of aux amplifier and UGF of main amplifier to
ensure stablility.
A good paper on pole zero doublets and their effects on settling is available at


rgds
Fred.
 

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