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Design >> Analog Design >> Pseudo differential amplifiers
https://designers-guide.org/forum/YaBB.pl?num=1152069738

Message started by mohanps on Jul 4^th, 2006, 8:22pm

Title: Pseudo differential amplifiers
Post by mohanps on Jul 4^th, 2006, 8:22pm

Are pseudo differential amplifiers supposed to burn lesser power
compared to fully differential ones with similar requirements
for slew rate, output swing and BW? Are there any good references
discussing actual implementation of pseudo differential amplifiers

Thanks
Mohan

Title: Re: Pseudo differential amplifiers
Post by Sid on Jul 15^th, 2006, 6:15pm

Hi,

A psedo differential amp basically does not have a bottom current source. Is this correct?

If I am correct, then it should not really affect your gain-BW-power trade-off. It will affect only your output swing and CMRR. If you have some kind of fast settling CMFB (common-mode feedback), then I think you can have "reasonable" CMRR and get away without problems in your pseudo differential amplifier.

Hope this helps.
-Sid