1/f noise, offset-voltage charge injection induced error cancelled op-amp sharing technique

摘要

The present invention provides an apparatus and method for reducing and canceling 1/f noise, offset voltage, and charge injection introduced in pipeline ADCs in conventional op-amp sharing techniques. The polarity of the residue signals is changed at each phase. During phase one, the residue signal of the operational amplifier is sampled on the capacitors with inverse polarity. During phase 2 the residue signal of the operational amplifier is sampled on the capacitors with the inverse polarity of phase one.