Patent ID: 8437154
Filing Date: 2013-05-07
Classification: H02M

Abstract:
1. A power supply controller, comprising: a switch duty cycle controller coupled to receive a feedback signal and a duty cycle adjust signal, the switch duty cycle controller coupled to generate a drive signal coupled to control switching of a switch coupled to an energy transfer element to regulate energy delivered from an input of a power supply to an output of the power supply; and a gain selector circuit coupled to receive an input voltage signal representative of a filtered direct-current (DC) input voltage of the power supply and to generate the duty cycle adjust signal received by the switch duty cycle controller in response to a magnitude of the filtered DC input voltage, wherein the switch duty cycle controller is coupled to limit a maximum duty cycle of the drive signal, and wherein a duty cycle of the drive signal is varied in response to a plurality of linear functions over a range of values of the input voltage signal.