Patent attributes
A power stage circuit generates an output signal according to an input signal and a control signal. A ramp generator circuit generates a ramp signal according to the control signal, the input signal, and the output signal. A calculation circuit generates a calculation signal according to the output signal and a reference signal. The calculation circuit operates in a first mode when the power converter operates in a light loading state, and the calculation circuit operates in a second mode when the power converter operates in a normal state. A control circuit generates the control signal according to the calculation signal and the ramp signal. The control circuit includes a comparator circuit and a control signal generator. The comparator circuit generates a comparison signal according to the calculation signal and the ramp signal. The control signal generator generates the control signal according to the comparison signal.