Abstract: A method of operating a switching power converter having at least one power switch controlled by a drive signal having a switching frequency is disclosed. The method includes monitoring an output power of the switching power converter, determining whether the output power has decreased below a threshold level and, in response to the output power decreasing below the threshold level, changing the switching frequency of the drive signal from a first switching frequency to a second switching frequency when an operating condition of the switching power converter is satisfied. Also disclosed are controllers and switching power converters (including PFC converters).

Abstract: A method of controlling a power converter having at least one switching device for supplying an output voltage and a load current to a load is disclosed. The method includes sensing the output voltage and sensing the load current. The method further includes controlling a duty cycle of the switching device according to the sensed output voltage and a voltage control loop when a rate of change of the load current does not exceed a threshold level. The method also includes adjusting the duty cycle of the switching device set by the voltage control loop when the rate of change of the load current exceeds the threshold level.

Abstract: A switching power converter includes an input for receiving an input voltage, an output for providing an output voltage, a controller, and a power circuit coupled between the input and the output and including at least one switch. The controller is configured to determine a duty cycle for the switch to regulate the output voltage and control the switch with a PWM drive signal having an on-time and an off-time. The PWM drive signal has a constant frequency and a duty cycle equal to the determined duty cycle when the determined duty cycle is greater than or equal to a minimum duty cycle. The PWM drive signal has a variable frequency and a duty cycle equal to the minimum duty cycle when the determined duty cycle is less than the minimum duty cycle.

Abstract: A method of operating a switching power converter having at least one power switch controlled by a drive signal having a switching frequency is disclosed. The method includes monitoring an output power of the switching power converter, determining whether the output power has decreased below a threshold level and, in response to the output power decreasing below the threshold level, changing the switching frequency of the drive signal from a first switching frequency to a second switching frequency when an operating condition of the switching power converter is satisfied. Also disclosed are controllers and switching power converters (including PFC converters).

Abstract: A switching power converter includes an input for receiving an input voltage, an output for providing an output voltage, a controller, and a power circuit coupled between the input and the output and including at least one switch. The controller is configured to determine a duty cycle for the switch to regulate the output voltage and control the switch with a PWM drive signal having an on-time and an off-time. The PWM drive signal has a constant frequency and a duty cycle equal to the determined duty cycle when the determined duty cycle is greater than or equal to a minimum duty cycle. The PWM drive signal has a variable frequency and a duty cycle equal to the minimum duty cycle when the determined duty cycle is less than the minimum duty cycle.

Abstract: A switching power converter has at least one electronic power switch. To minimize switching losses and optimize efficiency, the gate drive voltage level used to drive the electronic power switch is optimized. In an aspect, a digital controller generates optimizes the gate drive voltage using efficiency optimization algorithms, which in an aspect are programmed in the digital controller. In accordance with an aspect of the present disclosure, the switching power supply has at least two electronic power switches coupled in parallel. Optimization algorithms are used to determine the optimum number of switched electronic power switches that are actively being switched at a given time in order to achieve optimized efficiency for condition changes, such as input voltage variation, load and environmental temperature changes. In an aspect, the algorithms are programmed in a digital controller chip.

Abstract: A method of controlling a power converter having at least one switching device for supplying an output voltage and a load current to a load is disclosed. The method includes sensing the output voltage and sensing the load current. The method further includes controlling a duty cycle of the switching device according to the sensed output voltage and a voltage control loop when a rate of change of the load current does not exceed a threshold level. The method also includes adjusting the duty cycle of the switching device set by the voltage control loop when the rate of change of the load current exceeds the threshold level.