A semiconductor device with the highly precise current detecting function is provided. Current detection is performed using a semiconductor device in which two semiconductor chips are mounted in one package. The first semiconductor chip is provided with an electric power supply transistor to supply power to a load via a load driving terminal, and a current detection circuit to detect a current flowing through the load driving terminal. In the inspection process of the semiconductor device, the electrical property of the current detection circuit in the first semiconductor chip is inspected, and the information on a correction equation obtained as the inspection result is written in a memory circuit of the second semiconductor chip. The second semiconductor chip corrects the detection result obtained by the current detection circuit based on the information on the correction equation written in the memory circuit concerned.