Patent ID: 8484492

Claim:
An electronic device for being connected with an external power source, the electronic device comprising: a system unit; a control unit coupled with the system unit; a power control module coupled with the control unit; and a power supply unit coupled with the system unit, the control unit, and the power control module, wherein when the power supply unit is connected with the external power source, the power supply unit provides a first operating voltage for the power control module, the power control module provides a first control signal for the control unit, and the control unit receives the first control signal and provides a second control signal for the power supply unit according to the first control signal, allowing the power supply unit to sequentially provide a plurality of system working voltages for the control unit and the system unit, after a first predetermined time, the power supply unit provides a second operating voltage for the power control module, and according to the first operating voltage and the second operating voltage, the power control module changes a voltage level of the first control signal, allowing the control unit to change a voltage level of the second control signal; and wherein the power control module further comprises a delay latch circuit, and after the power supply unit is connected with the external power source for a second predetermined time, the delay latch circuit latches the voltage level of the first control signal provided by an inverse logic unit.