A semiconductor integrated circuit device includes a first semiconductor circuit, a second semiconductor circuit, a first control circuit and a second control circuit. The first and second semiconductor circuits are formed on a semiconductor substrate and operate using a voltage provided by an external power supply circuit as a power supply voltage. The first control circuit is formed on the semiconductor substrate and holds control information used to control the voltage generated by the external power supply circuit in accordance with operating performance of the first and second semiconductor circuits. The second control circuit controls a property of the first semiconductor circuit in accordance with the control information held by the first control circuit.