Patent ID: 6970124

Claim:
A comparator system, comprising: first and second differential pairs of transistors that respectively provide first and second output signals in respective response to a first input signal and a reference signal and that have offset voltages which vary in correspondence to applied tail currents; and a feedback network configured to provide: a) a second tail current to said second differential pair sufficient to substantially null said second output signal; and b) a first tail current to said first differential pair that substantially equals said second tail current; said first output signal thereby providing a comparison of said first input signal to said reference signal; wherein said first and second differential pairs of transistors are configured to have substantially-equal, nonzero inherent offset voltages and wherein said feedback network includes: a differential amplifier that provides a bias signal in response to said second output signal; and a current transistor which provides said second tail current to said second differential pair in response to said bias signal.