Thermistor drive circuit

Abstract

A thermistor drive circuit includes a plurality of driving resistors, at least one current correction resistor, a voltage measurement unit and a controller. The driving resistors are selectively connected to a thermistor for correcting a temperature characteristic of the thermistor whose resistance value changes in accordance with a temperature to be detected. The current correction resistor is selectively connected between a power supply and a ground. The voltage measurement unit measures a terminal voltage of the thermistor. The controller switches connection states of the driving resistors according to the terminal voltage. When switching the connection states of the driving resistors, the controller also switches a connection state of the current correction resistor to suppress a fluctuation of a power supply current before and after the switching of the connection states of the driving resistors.

Dependencies are inferred from the claim text.