Patent ID: 8339116

Claim:
A buck voltage converter, comprising: an upper switching transistor connected between an input voltage node and a phase node, the upper switching transistor turning on and off responsive to a first drive signal; a lower switching transistor connected between the phase node and ground, the lower switching transistor turning on and off responsive to a second drive signal; an inductor connected between the phase node and an output voltage node; control circuitry for generating the first drive signal and the second drive signal responsive to a feedback voltage monitored at the output voltage node and a phase voltage at the phase node; and wherein in a pulse frequency mode of operation the control circuitry turns off the upper switching transistor and turns on the lower switching transistor responsive to a determination that a predetermined period of time has occurred since a detection of a phase voltage switch at the phase node and turns off the lower switching transistor after the lower switching transistor has been turned on for a second predetermined period of time.