Multi-phase switching converter with overlap mode and control method thereof

A multi-phase switching converter, comprising:

• a plurality of switching circuits, wherein the output terminals of the plurality of switching circuits are coupled together to provide an output voltage to a load;
• and
• a controller configured to generate a plurality of control signals to turn on the plurality of switching circuits successively;
• wherein
• when a load current increase is detected, the controller operates in an overlap mode and after a current switching circuit of the plurality of switching circuits turns on, at least two switching circuits are turned on simultaneously, and wherein after the controller exits out of the overlap mode, the controller resumes to successively turning on the plurality of switching circuits;
• and
• wherein the controller compares the output voltage with a plurality of threshold voltages to generate a plurality of load indication signals, and wherein based on the plurality of load indication signals, the controller detects whether the load current is increased and determines the number of the switching circuits to simultaneously turn on in the overlap mode.

A control method used in a multi-phase switching converter, wherein the multi-phase switching converter comprises a plurality of switching circuits, the output terminals of the plurality of switching circuits are coupled together to provide an output voltage to a load, the control method comprises:

• turning on the plurality of switching circuits successively;
• comparing the output voltage with a plurality of threshold voltages to generate a plurality of load indication signals;
• detecting whether a load current is increased based on the plurality of load indication signals;
• operating in an overlap mode and turning on at least two of the switching circuits simultaneously when a load current increase is detected, wherein the number of the switching circuits to be simultaneously turned on is determined based on the plurality of load indication signals;
• and
• resuming the turning on of the plurality of switching circuits successively after exiting out of the overlap mode.