Gas detecting apparatus and gas detecting method

摘要

A gas detecting apparatus including: a heating resistor exposed to a detected atmosphere, and a control circuit for controlling the heating resistor at two different temperatures, wherein each output voltage from the heating resistor corresponding to the different temperatures is detected when the heating resistor is controlled to the different temperatures, and a state of a gas is obtained based on the detected output voltage. For example, two different offset voltages are set, each potential difference obtained by subtracting each of the offset voltages from corresponding detected output voltages is amplified and the state of the gas is obtained using the amplified potential differences.

主权项

1. A gas detecting apparatus comprising:
an electronic controller; a heating resistor exposed to an atmosphere; a control circuit for controlling the heating resistor to exhibit two different temperatures; and an amplifying unit, wherein an input offset voltage that is input to the amplifying unit is switched to any of two different offset voltages in response to a control signal from the electronic controller, wherein the control circuit detects output voltages from the heating resistor corresponding to the two different temperatures, wherein potential differences, which are obtained by subtracting respective ones of the two different offset voltages from corresponding ones of the detected output voltages, are amplified by the amplifying unit, and wherein the electronic controller detects a state of a gas in the atmosphere based on the amplified potential differences.