Patent ID: 7936087

Claim:
A switching controller for power converters, comprising: an input circuit, coupled to an input terminal, for receiving an input signal, and configured for receiving a switching signal for generating a phase-shift signal; a control circuit, coupled to the input circuit, the control circuit generates the switching signal and the power converters are switched according to the switching signal, wherein the control circuit comprises a flip-flop and an AND gate for receiving the phase-shift signal and generating the switching signal at an output terminal of the AND gate; a resistor, coupled to the input circuit for determining a delay time, wherein the switching signal is generated in response to the input signal, wherein the delay time is the time from a low-to-high transition of the input signal to when the phase-shift signal is allowed to be output, and a pulse width of the switching signal is determined by a pulse width of the input signal; and an integration circuit, for generating an integration signal in response to the pulse width of the input signal, wherein the switching signal is disabled once a voltage level of the integration signal is lower than a predetermined threshold voltage supplied to a comparator in the switching controller, wherein an output terminal of the comparator is further coupled to an input terminal of the flip-flop for controlling the switching signal.