A semiconductor integrated circuit, supplied with a power source voltage generated by a power supplier and having a level determined in accordance with an analog signal, includes: an output unit outputting, as the analog signal, an output voltage signal indicating the power source voltage; an input unit including an input interface identical in specifications to an output interface of the output unit, and receiving an input signal indicating a voltage and input from an outside of the semiconductor integrated circuit; and a voltage control circuit generating the output voltage signal, based on the input signal and operating voltage information indicating a voltage required for an operation of the semiconductor integrated circuit.