On Sensitivity of Bias Operation Point In Transistors with Moderate Inversion

Abstract

The paper analyses sensitivity, with respect to the threshold voltage, of bias operation point in the analog circuits using moderate inversion. It is shown that this regime is highly sensitive with respect to the threshold voltage variation. Such high sensitivity imposes unrealistic requirements on the threshold voltage tolerances, so that it is practically impossible to design an amplifier with moderate inversion in the stages without adaptable or tunable threshold voltage. It is also shown that, as a result of this mode of inversion, some important design metrics (cancelling of the third order distortion) are unrealizable.