raja.cedt wrote on May 27th, 2009, 11:08pm:hi,
Can any body please tell me how to decide cmfb loop UGB from amplifier specification?And is there any relation between DMFB UGB and this?
Thanks,
Rajasekhar.
Absolutely.
It depends what freqs you want to correct CM errors.
I've never really found a scenario of when I'd want CM correction BW to be Less than the DM signal BW.
For that reason, and there is usually an extra pole, CM loop stability is often the most challenging part of a diff'l circuit.
GHLM text, 4 or 5th edition has a nice write up on this.
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Wave