Patent ID: 7523326

Claim:
A cellular phone, comprising: a power supply circuit which supplies each unit of a circuit with power obtained from a battery; a counter unit which counts the elapsing time of a suspension state; a mode switching unit which switches the cellular phone from a normal operating state to the suspension state in which power is supplied to only a part of the circuit from the power supply circuit and nullifies the operation of a monitor timer for detecting the abnormal operation of a CPU if power is switched off during operation, and release the suspension state and switches the state to a power-off state in which the power supply to internal circuits is stopped if the counter counts that the suspension state has continued for a prescribed time or more; and a battery voltage detection unit which detects whether battery voltage exceeds a prescribed value, wherein if the battery voltage detected by said battery voltage detection unit when power is switched off is less than the prescribed value, said mode switching unit switches the cellular phone to the power-off state in which power is not supplied to the internal circuits.