Detection circuit applied to a connecting port

A detection circuit applied to a connecting port, comprising:

• a connector, comprising a first detection terminal and a second detection terminal, wherein the second detection terminal is electrically connected to a first reference potential;
• and
• a processing circuit, electrically connected to the first detection terminal and is configured to receive a power supply signal, wherein the connector is configured to be connected to the connecting port, the first detection terminal is electrically connected with the second detection terminal through the connecting port, and the first detection terminal is configured to be connected to a detection resistor of the connecting port, so that the processing circuit detects a detection potential on the first detection terminal, and a magnitude of the detection potential varies with a resistance of the detection resistor.