Patent ID: 8391027
Filing Date: 2013-03-05
Classification: H02M,Y02B,Y10T

Abstract:
1. A switching power supply controller comprising: a first output configured to control a switch current through both a switch and an inductor in order to regulate an output voltage to a desired value wherein the switching power supply controller is configured to form a switching drive signal in order to enable and disable the switch responsively to the switching drive signal and wherein disabling the switch creates oscillations of a switch voltage across the switch, the oscillations forming a plurality of peak values and a plurality of valley values of the switch voltage; a first input configured to receive a sense signal that is representative of a value of the output voltage; a detector configured to detect the plurality of valley values and form a plurality of valley detection signals responsively to the plurality of valley values wherein a first valley detection signal is representative of detecting a first valley value of the plurality of valley values and a second valley detection signal is representative of detecting a second valley value of the plurality of valley values that is different from the first valley value; and a first circuit configured to use a first value of the sense signal and the first valley detection signal to selectively enable the switch during the first valley value that occurs during a first switching cycle of the switching drive signal, the first circuit configured to selectively enable the switch during the first valley value responsively to a second value of the sense signal and the first valley detection signal during a second switching cycle of the switching drive signal which is different from the first switching cycle, the second value of the sense signal being within a first range around the first value of the sense signal.