Load transient detection method used in multi-phase converters

A controller of multi-phase converters, wherein the multi-phase converter includes a plurality of switching circuits coupled in parallel between an input voltage and a load, and the controller comprises:

• a comparison unit configured to receive a feedback signal indicative of an output voltage provided to the load, wherein the comparison unit compares the feedback signal with a reference signal to generate a comparison signal;
• an on-time generation unit configured to generate an on-time threshold;
• a load current comparison unit configured to receive a load current sensing signal indicative of a load current, wherein the load current comparison unit compares the load current sensing signal respectively with a plurality of threshold voltages to generate a plurality of current comparison signals;
• a period detection unit coupled to the comparison unit and configured to detect a period of the comparison signal;
• a transient detection unit coupled to the period detection unit, wherein the transient detection unit compares the detected period of the comparison signal with a time threshold to determine whether a transient rise of load current has occurred, and generates a transient detection signal;
• and a control unit coupled to the comparison unit, on-time generation unit, load current comparison unit and transient detection unit, wherein based on the comparison signal, on-time threshold, the plurality of current comparison signals and the transient detection signal, the control unit generates control signals to control the plurality of switching circuits.

A load transient detection method used in multi-phase converters, wherein the multi-phase converter includes a plurality of switching circuits coupled in parallel between an input voltage and a load, and the load transient detection method comprises:

• comparing a feedback signal with a reference signal to generate a comparison signal, wherein the feedback signal is indicative of an output voltage provided to the load;
• detecting a period of the comparison signal;
• generating a plurality of time thresholds;
• selecting one of the plurality of time thresholds in accordance with a number of switching circuits currently under power operation;
• and comparing the selected time threshold with the detected period of the comparison signal to determine whether a load transient has occurred.