| 摘要 |
PROBLEM TO BE SOLVED: To allow a DAP (digital audio player) 20 to charge a battery even if no data is supplied to data lines D+ and D- from a USB host 2.SOLUTION: When a detection unit 3 detects that data is outputted from a USB host 2, a USB switch 4 is switched to supply data from the USB host 2 to the DAP 20 through the data lines D+ and D-. The DAP 20 is supplied with data from the data lines D+ and D-, and the DAP 20 charges the battery. When the detection unit 3 detects that no data is outputted from the USB host 2, the USB switch 4 is switched to supply a predetermined voltage from a voltage supply unit 5 to the DAP 20 through the data lines D+ and D-. Even if no data is outputted from the USB host 2, the DAP 20 charges the battery. |
