Patent ID: 7131018

Claim:
An electronic apparatus having a semiconductor integrated circuit and power supplying means, the apparatus comprising: a main circuit, disposed in the semiconductor integrated circuit, the main circuit having at least a CPU, power being supplied to the main circuit through the power supplying means; a standby controlling circuit disposed in the semiconductor integrated circuit, power being supplied to the standby controlling circuit through the power supplying means when the standby control circuit is in an operation mode and a standby mode; wherein when the standby controlling circuit receives a standby command from the CPU, the standby controlling circuit turns off a switch, within the power supplying means, that provides power to the main circuit; wherein when a wakeup cause takes place, the standby controlling circuit holds information about the wakeup cause in the standby mode and turns on the power supplied to the main circuit by the power supplying means; and wherein the CPU of the main circuit identifies the wakeup cause, by accessing the information held in the standby controlling circuit, and executes a process corresponding to the identified wakeup cause.