THE MINIMIZATION METHOD OF THE THERMAL DRIFT INFLUENCE ON ANALOG INTEGRATED CIRCUITS

Abstract

The existing offset cancellation methods are based on digital-to-converters (DAC) and the calibration paths. During thermal drift the parameters of transistors in calibration pa¬t¬h change, which increase the offset of the system. The proposed offset cancellation meth¬od includes current DAC which is directly connected to the output of the system. The absence of the calibration path makes the circuit more stable during temperature drifts without voltage-current-voltage conversion. The offset variation of the circuit during thermal drift is reduced 19 times (1.42 mV). The circuit occupies 43.2 % less area as in the current DAC, only transistors have been used instead of the resistor-transistor structure of voltage DAC. Power consumption increases 7 % as the branch of the current DAC is always on.