ipsc
Member level 4
winsonpku said:could you explain the second issue in details?
I can't understand low Vdsat can reduce the offest of opamp
Suppose there is a diffrence of 'dI' in diff-pair currents due to mismatch. This will be seen at the input as an I/P OFFSET='dI/gm'. Here 'gm' is 'gm' of diffpair. So to have low offset 'gm' should be more i.e. for a given 'Id', 'vdsat' should be low.
(Ref: Baker, Lee, Boyce).
Hope I am able to make my point clear.
Regards