Patent ID: 8450990

Claim:
A method of controlling a regulator having an input voltage and an output voltage, comprising: setting a reference voltage to a first voltage level; turning on a first driver; determining a duration ratio having a first time period over the first time period and a second time period; the first time period and the second time period indicating a duration when the first driver and a second driver is on, respectively; generating a second voltage level based on the duration ratio and a ripple voltage that is a difference between a high threshold voltage and a low threshold voltage; turning off the first driver and turning on the second driver based on a relationship between the second voltage level and a voltage level of the output voltage; turning off the second driver when a current flowing through a node of the output voltage reaches a pre-determined level; and generating a change in the first time period based on the duration ratio and a voltage difference between a peak of the output voltage and the high threshold voltage.