Patent ID: 8334672

Claim:
A charging circuit for identifying a power source connected to a portable electronic device, comprising: a connector configured for directly connecting to the power source, the connector having a voltage bus contact, a ground contact, a positive data contact and a negative data contact; an identifying circuit connected to the positive data contact or the negative data contact to identify the power source as a computer or an adapter and generating a configuration signal; and a central processing unit directly connected to the identifying circuit, the central processing unit receiving the configuration signal and operating in a corresponding charging mode according to the configuration signal; wherein the identify circuit is a MOSFET, a gate of the MOSFET connects to the positive data contact or the negative data contact of the connector, a source of the MOSFET connects ground, a drain of the MOSFET connects to the central processing unit, when the power supply is identified as the computer, the MOSFET is alternatively switched on and off; when the power supply is identified as the adapter, the MOSFET is always switched on or off.