Electronic device and electronic-device control method
A diode is provided in a first supply route for the electric power from an AC adaptor, rectifies the current from the AC adaptor and, at the output side thereof, is connected to a second supply route for the electric power from an AC adaptor. A detecting unit is connected to the input side of the diode in the first supply route and, based on the voltage that is input from the first supply route, detects whether the AC adaptor is connected. A resistance control unit reduces the combined resistance between the ground and the input side of the diode when the temperature of the device, including the diode, is equal to or more than a predetermined temperature.
1. An electronic device comprising:
a rectifying device that is provided in a first supply route for an electric power from a first external power source, rectifies a current from the first external power source and, at an output side thereof, is connected to a second supply route for an electric power from a second external power source;
a detecting unit that is connected to an input side of the rectifying device in the first supply route and, based on a voltage that is input from the first supply route, detects whether the first external power source is connected; and
a resistance control unit that reduces a combined resistance between a ground and the input side of the rectifying device when a temperature of a device, including the rectifying device, is equal to or more than a predetermined temperature.
2. The electronic device according to claim 1 , wherein the resistance control unit reduces a combined resistance by adding a second resistor in parallel to a first resistor that is provided between the ground and the input side of the rectifying device.
3. The electronic device according to claim 1 , wherein the resistance control unit compares a predetermined voltage and a divided voltage that passes through a thermistor whose resistance value becomes equal to or less than a predetermined value at equal to or more than the predetermined temperature, detects that the temperature of the device is equal to or more than the predetermined temperature when the divided voltage exceeds the predetermined voltage, and reduces the combined resistance when it is detected that the temperature of the device is equal to or more than the predetermined temperature.
4. An electronic-device control method comprising:
reducing a combined resistance between a ground and an input side of a rectifying device when a temperature of a device, including the rectifying device, is equal to or more than a predetermined temperature, the rectifying device being provided in a first supply route for an electric power from a first external power source, rectifying a current from the first external power source and, at an output side thereof, being connected to a second supply route for an electric power from a second external power source; and
detecting whether the first external power source is connected based on a voltage on the input side of the rectifying device in the first supply route.