Hi,

In designing opamp circuit, is it desirable to bias output common mode different from target Vout_CM to have consistent feedback current to the input pairs, or should ckt be biased so that Vout_cm is almost the same as its target value, what are the considerations here?

thanks,

Steve

Echoing what Raja said, usually the desired common-mode level is a the point of maximum swing, and generally it is a convenient voltage to generate.  (for example, sometimes it is mid-supply).  But, it really doesn't make much difference because the feedback loop will take care of any offsets.