Patent ID: 7652459

Claim:
A method for adaptively controlling a power stage in an electronic system, comprising: obtaining an input power of the power stage; obtaining the current duty cycle of a synchronous power switch in the power stage; adaptively changing the duty cycle of the synchronous power switch until the minimum input power is obtained including: increasing or decreasing the duty cycle of the synchronous power switch; checking whether the input power decreases as a result of the increase or decrease of the duty cycle of the synchronous power switch; if the input power does not decrease as a result of the increase or decrease of the duty cycle of the synchronous power switch, determining whether the power stage operates in a continuous conduction mode (“CCM”) or a discontinuous conduction mode (“DCM”); and if the power stage operates in CCM mode, adaptively changing the duty cycle of the synchronous power switch again until the minimum input power is obtained after waiting for a predetermined number of switching cycles; and using the duty cycle that corresponds to the minimum input power for the synchronous power switch.