SEMICONDUCTOR DEVICE

A semiconductor device capable of charging that is less likely to cause deterioration of a power storage device is provided. The amount of a charging current is adjusted in accordance with the ambient temperature. Charging under low-temperature environments is performed with a reduced charging current. When the ambient temperature is too low or too high, the charging is stopped. Measurement of the ambient temperature is performed with a memory element using an oxide semiconductor. The use of a memory element using an oxide semiconductor enables measurement of the ambient temperature and retention of the temperature information to be performed at the same time.