Patent ID: 7271597
Filing Date: 2007-09-18
Classification: H04B

Abstract:
1. An electronic device comprising: a first signal path that supplies an input signal; a first power supply path that supplies a voltage; a connector that transmits to an external device the input signal on which the voltage has been superposed, said connector being supplied with the input signal by way of the first input path and supplied with the voltage by way of the power supply path; a first power supply switch inserted into the first power supply path; an amplitude detector that detects at the connector an amplitude of the input signal on which the voltage has been superposed; and a control section that determines on the basis of a detection output from the amplitude detector, at least a connection condition of the external device to the connector is any one of a first condition and a second condition, said first condition in which the external device is not connected to the connector, and said second condition in which the external device is connected to the connector, and, on the basis of the connection condition, controls the first power supply switch to perform any one of turning on and off the first power supply switch.