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Design >> Analog Design >> Continuous Time CMFB
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Message started by Edward on Feb 13^th, 2004, 5:39am

Title: Continuous Time CMFB
Post by Edward on Feb 13^th, 2004, 5:39am

Hi,

in many text books and papers, it is said that in order to use cmfb, we can feedback the controlled voltage of cmfb to either the current tail or to the load to the fully differential op amp.

so what is the advantages/disadvantages by choosing to feedback to current tail or load?

how do we decide?

thx

Title: Re: Continuous Time CMFB
Post by fehler on Mar 19^th, 2004, 4:32am

I am afraid that the current tail is not a best choice.
For that if so, the CMFB loop will contain two many
high resistance nodes, then it is difficult to make it
stable while wide bandwidth.
I just guess.