Patent ID: 7675281

Claim:
In a power converter system having first and second switches connected in a half-bridge arrangement at a common node from which current flows through an inductor to a regulated output terminal, wherein the regulated output terminal is connectable to an output capacitor and a load, wherein the first and second switches are turned on and off in cycles, circuitry comprising: means for initiating a cycle in which the first switch is turned on; means for developing a timer based on the on-time of the first switch during the cycle; means for turning off the first switch and turning on the second switch during the cycle; and means for outputting a control signal to turn off the second switch when either the timer expires or a new cycle is initiated to turn on the first switch, thereby providing synchronous rectification in the power converter system; wherein the means for developing a timer comprises a timing capacitor which charges for the on-time of the first switch during the cycle and discharges to provide the timer; wherein the timing capacitor is charged from the common node.