Patent ID: 7944247

Claim:
An operating circuit, comprising: a differential amplifier stage, for amplifying a differential input to generate a differential output, the differential amplifier stage having a first input node for receiving a first input signal of the differential input, a second input node for receiving a second input signal of the differential input, a first output node for outputting a first output signal of the differential output, and a second output node for outputting a second output signal of the differential output; an offset current stage, coupled to the first output node and the second output node, for inducing a first offset current at the first output node and a second offset current at the second output node, wherein a current value of the first offset current is different from a current value of the second offset current; and a first clamping device, coupled to the first output node, for selectively clamping the first output signal at the first output node according to the first output signal at the first output node.