Abstract: A power supply including a regulation circuit that maintains an approximately constant load current with line voltage. An example circuit includes a switch including first, second and third terminals. The first terminal is coupled or decoupled to the second terminal in response to a control signal received at the third terminal. Voltage sense circuitry is included and is coupled to sense a voltage drop across the switch. The voltage drop is representative of a current in the switch during an on time of the switch. The voltage sense circuitry has a variable current limit threshold that increases between a first level and a second level during the on time of the switch. The control signal is responsive to the variable current limit threshold to regulate a power supply with an output characteristic having an approximately constant output voltage below an output current threshold and an approximately constant output current below an output voltage threshold.

Abstract: Various techniques directed to providing temporary peak power from a switching regulator are disclosed. In one aspect, a switching regulator includes a switch that is to be coupled between a power supply input and an energy transfer element of the power supply. A controller is coupled to be responsive to a feedback signal to be received from an output of the power supply. The controller is coupled to switch the switch in response to the feedback signal to regulate the output of the power supply. An oscillator is coupled to provide an oscillating signal to the controller to determine a maximum switching frequency of the switch. The oscillating signal is coupled to oscillate at a first frequency under a first moderate load condition at the power supply output. The oscillating signal is coupled to oscillate at a second frequency under a second peak load condition at the power supply output.