An IC which includes a first circuit and a plurality of first paired terminals each including a first power supply terminal and a first GND terminal which are connected to the first circuit, and a second circuit and a plurality of second paired terminals each including a second power supply terminal and a second GND terminal which are connected to the second circuit. The first and second paired terminals are isolated inside. A printed board with the IC mounted has an inductor which is provided in a route that guides a wiring line from the first GND terminal to the second GND terminal and the GND of the printed board. The printed board has a portion where each of the first GND terminals is arranged inside the terminal array of the IC. The inductor suppresses a high-frequency potential variation generated by the operation of the first circuit.