Frequency Modulation Controller, Switch Mode Power Supply Including The Same, And Switching Operation Frequency Modulation Method

摘要

The present invention relates to switching operation frequency modulation for reducing an output voltage ripple.;The present invention uses a ripple of an input voltage so as to modulate a switching operation frequency of a switch mode power supply. A sensing voltage corresponding to the input voltage is received, a current ripple that is proportional to a difference between a peak value of the sensing voltage and the sensing voltage is generated, and a modulation control signal that is variable by the current ripple is generated. The present invention modulates a switching frequency by using an oscillator signal that is variable by the modulation control signal, and reduces the output voltage ripple.