Tung & Associates
Flyback power converter with weighted frequency and quasi-resonance
The present invention provides a flyback power converter and a control circuit and a control method thereof. The flyback power converter includes: a power stage circuit, a voltage sense circuit, a current sense circuit, and a control circuit. When the flyback power converter operates in a quasi-resonant mode, the control circuit determines a time point of turning OFF a power switch in the power stage circuit according to a current sense signal, a pulse width modulation (PWM) frequency of a PWM signal, and a predetermined threshold, wherein the control circuit adaptively adjusts an ON period of the power switch, or adaptively adjusts an operation bandwidth or an amplifier gain of an error amplifier circuit in a feedback control loop according to the PWM frequency to mitigate an output voltage ripple.
RICHTEK TECHNOLOGY CORPORATION
H Y H H
H02M Y02B H02M H02M
additional additional inventional inventional
Tzu-Chen Kuang-Fu Li-Di
Lin Chang Luo