The touch detecting circuit is a capacitive detecting circuit correctable with a sensor capacitance, and includes an integration capacitance. In the touch detecting circuit, a sensor capacitance connected with the touch detecting circuit is charged and discharged; electric charges to input and output for charging and discharging the sensor capacitance are cumulatively added to the integration capacitance. The electric charges to he added to the integration capacitance are inverted in polarity according to directions of charge transfer accompanying the charge and discharge. Not only when charging the sensor capacitance, but also when discharging the sensor capacitance, the absolute values of electric charges to be moved are integrated and therefore, the amount of signals is doubled.