Static error in the temperature constant measurement configurations due to DC amplifier offset voltage

The DC amplifier offset voltage introduces dynamic and static errors in measurements based on heated sensors at constant temperature configuration. It is shown, in the case of a radiometer, the variation of static errors in function of offset voltage for configurations of feedback based on analogic voltage control and on pulse width modulation - PWM. These errors increase with offset voltage and are similar in PWM configuration, decreasing with pulse amplitude.