To reduce power consumption from a battery by maintaining a power- off operation without contradiction even though the operation of a microcomputer 13 is stopped or falls into an insufficient state.

A power supplying means such as a battery and a load is connected by a MOSFET switch which has a few leakage current and a little of forward voltage drop, interruption is controlled, and the connection and interruption control state is controlled while being held by using a latch composed of a CMOS circuit driven by the battery. The MOSFET switch is continuously interrupted and a stable operation can be obtained because the state can be held by resetting the latch even though a signal of a controlling part becomes unstable. Since the latch is a CMOS and the leakage current is extremely small, power consumption from the battery can be reduced when the power is turned off.