Comparator with offset canceling function and D/A conversion apparatus with offset canceling function

摘要

A comparator with an offset canceling function and a D/A conversion apparatus capable of canceling an input/output offset with high accuracy using this comparator. To eliminate unbalance between right and left currents of the differential circuit making up the comparator, the phase of a single end output signal of the differential circuit is inverted and the inverted signal is fed back to one substrate of the differential pair MOS transistors as a substrate bias. Threshold voltages of the MOS transistors are changed and the current capacities of the transistors are adjusted in this way.