US Patent 7132883 Chopper chopper-stabilized instrumentation and operational amplifiers

Chopper chopper-stabilized instrumentation and operational amplifiers having ultra low offset. The instrumentation amplifiers use current-feedback, and include, in addition to a main chopper amplifier chain, a chopper stabilized loop for correcting for the offset of the input amplifiers for the input signal and for receiving the feedback of the output voltage sense signal. Additional loops, which may include offset compensation and autozeroing loops, may be added to compensate for offsets in the chopper stabilized loop for correcting for the offset of the input amplifiers. Similar compensation is disclosed for decreasing the offset in operational amplifiers.