To reduce power consumption by reducing power consumption when a load circuit is in a stand-by mode in a power voltage dropping circuit making power source voltage supplied from outside drop.

At the time of the stand-by mode, a reference voltage generation circuit 31 is made inactive to prevent a power source current from flowing and also in an operation amplifier 53, the feedback control operation of dropping voltage VOUT is stopped to prevent a power source current necessary for feedback control operation from flowing. In addition, a pMOS transistor 18 is turned off and dropping voltage VOUT is obtained by a voltage dividing circuit consisting of resistors 23, 20 and 21 to secure data holding operation in the loading circuit 12.