Patent ID: 7453709
Filing Date: 2008-11-18
Classification: G06F,H02M

Abstract:
1. A power supply, comprising: an energy transfer element coupled between an input and an output of the power supply; a switch coupled to the input of the energy transfer element; and a controller coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply, wherein the controller is coupled to limit a maximum on time period of the switch to a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions, wherein the second maximum on time period is controlled by extending the oscillation time period of an oscillator of the controller in response to the input voltage level of the power supply.