Absolute voltage amplification using dynamic feedback control

A new principle of voltage amplification that is insensitive to drift and aging effects of the feedback resistors is presented. The effect of mismatch of these resistors is reduced to a second-order effect which results in a total gain error of less than 5/spl times/10/sup -6/ without the need for any calibration. Moreover, the long-term stability of the whole amplifier is guaranteed by the design when used as a chopper amplifier.