Patent ID: 8797013

Claim:
An adaptive slope-compensation method applied to a switch-mode power supply, the switch-mode power supply having a power switch and an inductor coupled to an input power, the power switch controlling the inductor to store energy or release energy to generate an output voltage, the adaptive slope-compensation method comprising: detecting an inductor current passing through the inductor, thereby generating an inductor-current detecting voltage; detecting a duty cycle of the power switch; detecting a maximum and a minimum of the inductor-current detecting voltage and determining a voltage variation of the inductor-current detecting voltage according to the maximum and the minimum of the inductor-current detecting voltage when the power switch is turned on; generating a slope-compensation signal according to the voltage variation and the duty cycle; and adjusting a timing to turn on or turn off the power switch according to the slope-compensation signal; wherein detecting the maximum of the inductor-current detecting voltage comprises: continuously comparing the inductor-current detecting voltage with a first recorded voltage when the power switch is turned on; setting voltage level of the first recorded voltage to be equal to voltage level of the inductor-current detecting voltage when the inductor-current detecting voltage is higher than the first recorded voltage; and outputting the maximum of the inductor-current detecting voltage according to the first recorded voltage.