| abstract |
[PROBLEMS] To reduce current consumption in a self-refresh mode under room temperature conditions. SOLUTION: A bias voltage B having a positive temperature dependency is supplied to a current source (3) for determining an operation current of a refresh timer (912) for issuing a refresh request (PHY). An IST is provided to make the drive current of the current source (3) have a positive temperature characteristic. Thus, when the temperature rises, the refresh cycle of the refresh timer shortens the issuance interval, and when the temperature falls, the refresh request issuance interval is lengthened, thereby reducing the current consumption of the refresh at room temperature. |