| 摘要 |
A signal processing device is provided including: an alternating voltage generation section that generates a square shaped alternating voltage from plural direct voltages, and applies the square shaped alternating voltage to a sensor that is either a temperature detection sensor or a humidity detection sensor; a current-voltage conversion section that converts current of an output signal output from the sensor to an analog voltage; a selector section that selects a range of the current convertible by the current-voltage conversion section from one or other of plural current ranges; and a resistance value computation section that computes the resistance value of the sensor, based on the voltage value of the analog voltage converted by the current-voltage conversion section, the range of current convertible by the current-voltage conversion section, and the voltage value of the voltage generated by the alternating voltage generation section.
|
