摘要 |
A frequency-jitter-controller for a power-converter is provided, and which includes a first and a second capacitance units, a first and a second charge-discharge control units, a comparing unit and a control unit. Both capacitance units are charged to a crossing-voltage during a charging phase and discharged to a reference voltage and a clamp voltage respectively during a discharging-phase in response to operations of both charge-discharge control units. The comparing unit outputs a pulse signal, compares voltages of both capacitance units during the charging phase, and compares the voltage of the first capacitance unit and the reference voltage during the discharging phase. The control unit generates a frequency jitter control signal according to the pulse signal to adjust a rising rate of the voltage on the second capacitance unit, so as to change a frequency of the pulse signal, and thus reduce EMI generated by switching switch-elements in the power-converter. |