| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor device which allows shift and return of an operation mode within a short period thereby reducing electric power consumption even in the case of a short period operation stop of a circuit block. <P>SOLUTION: The semiconductor device includes a plurality of power supply switches provided in a plurality of parallel channels supplying currents to inner circuits and having a first power switch and a second power switch, a power supply voltage monitoring circuit for detecting that whether a voltage applied to the inner circuit is lower than a predetermined voltage, and a control circuit for supplying a clock to the inner circuit and maintaining the first power switch at a conduction state in a first mode, for stopping clock supply to the inner circuit and maintaining the first and second power switches at a cut-off state in a second mode, and for stopping clock supply to the inner circuit and maintaining the first power switch at the cut-off state while intermittently setting the second power switch at a conduction state based on the detection result of the power supply voltage monitoring circuit in a third mode. <P>COPYRIGHT: (C)2012,JPO&INPIT |
