Synchronous rectification chip pin multiplexing technology

A synchronous rectifier chip, used in a secondary side of a switching power supply comprising a protocol chip, the synchronous rectifier chip comprising:

• a control pin configured to control turning on and turning off of a rectifier power tube according to an input signal;
• and
• a receiving pin connected to the protocol chip and configured to receive a power supply demand signal characterizing a load device connected to the switching power supply from the protocol chip, and adjust a working mode of the synchronous rectifier chip based on the received power supply demand signal.

A protocol chip, used in a secondary side of a switching power supply comprising a synchronous rectifier chip, the protocol chip comprising:

• a detection pin configured to detect a power supply demand of a load device connected to the protocol chip;
• and
• an output pin configured to transmit a power supply demand signal representing the power supply demand detected by the detection pin to the synchronous rectifier chip, to cause the synchronous rectifier chip to adjust a working mode of the synchronous rectifier chip based on the power supply demand signal.