| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit device wherein unstable operation of a MOS transistor circuit and increase of consumption current can be prevented, by reducing the power source voltage as low as possible in a range in which an internal circuit is normally operated, and restraining the increase of the gate current. SOLUTION: The power source voltage of a power source voltage generating circuit 11 is controlled in such a manner that the power source voltage is reduced in a range in which the internal circuit 14 is normally operated, by using a first control signal outputted from a power source voltage estimating circuit 12. The power source voltage of the power source voltage generating circuit 11 is also controlled in such a manner that the power source voltage generated in the power source voltage generating circuit 11 is not increased higher than or equal to a prescribed voltage, by using a second control signal outputted from a prescribed voltage detecting circuit 13. Since control is also performed by using the prescribed voltage detecting circuit 13, in addition to the control of power source voltage by using the power source voltage estimating circuit 12, excessive increase of the power source voltage of the power source voltage generating circuit 11 is restrained, and unstable circuit operation and remarkable increase of a consumption current are prevented. |
