Abstract: Provided is a receiving circuit that operates in a power supply system different from a transmitting circuit outputting a transmission signal and receives the transmission signal through an AC coupling device where a primary coil through which the transmission signal flows and a secondary coil having a center tap to which a specified voltage is supplied from an external terminal are magnetically coupled, which includes a pulse width amplifier circuit that holds pulse signals appearing at both ends of the secondary coil for a specified period of time and outputs them as hold signals, respectively, and a differential amplifier that compares a voltage of the hold signal and a voltage of the hold signal and outputs a comparison result.

Abstract: The receiver, which enables rejection of image signals with higher accuracy over wider frequency band, can be provided as a low IF receiver by inputting a calibration signal of frequency fi (1?i?N) before reception of signals and determining the frequency response fa(z) to fd(z) of a calibrating filter in a filter mismatch calibrating circuit (FIL_CAL) 195 to make zero amplitude and phase mismatches between the I component and Q component of the quadrature demodulation signal at the frequency fIFi.