摘要 |
A comparator comprises a differential amplifier type including input MOSFETs receiving differential input of a reference voltage and an input voltage, load MOSFETs for the input MOSFETs, and a constant current source to supply the sources of the input MOSFETs. The comparator comprises a Zener diode that is connected between the gate and source of the input MOSFETs and exhibits a breakdown voltage lower than the withstand voltage of the gate oxide film of the input MOSFET. Another comparator further comprises a feedback MOSFET that performs negative feedback of an output voltage of a main body comparator to the gates of the load MOSFETs to restrict the amplitude of the output voltage. Still another comparator further comprises a semiconductor rectifying element that exhibits a reverse-blocking characteristic higher than the power supply voltage and is interposed between the constant current source and the source of each of the input MOSFETs. |