| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device with less power consumption.SOLUTION: In a semiconductor device including a CPU, the frequency of access to a cache memory is monitored. In the case where the access frequency is uniform, supply of a power supply voltage to the CPU is stopped. In the case where the access frequency is not uniform, stop of supplying the power supply voltage is performed on cache memories with a time interval, and eventually, supply of the power supply voltage to the CPU is stopped. Further, write back processing is efficiently performed in accordance with determination of a dirty bit, so that power saving of the semiconductor device can be further achieved. |
