Controller for a switched mode power converter

摘要

A switched mode power converter controller outputs a switch control signal for a switch, receives sensed voltage and primary current input signals, and includes a constant current mode controller to process voltage input signals and generate output control signals for controlling converter peak current and/or switching frequency operational; a constant voltage mode controller processes the voltage input signal and generates output control signals for converter peak current and/or switching frequency operational parameters; a primary peak current adjuster processes primary current input and output control signals from the current and voltage mode controllers to configure the switch control signal to turn off the switch; a switching frequency adjuster processes output control signals from the current and voltage controllers to configure the switch control signal to turn on the switch. The constant current controller is enabled if the constant voltage controller signals represent operation with maximum peak current and switching frequency.

主权项

1. A controller for a switched mode power converter having a switch, wherein the switched mode power converter can operate in a constant current mode of operation and a constant voltage mode of operation, the controller is configured to output a switch control signal for the switch and receive a sensed voltage input signal and a primary current input signal, wherein the controller comprises:
a constant current mode controller configured to process the sensed voltage input signal and generate a first plurality of output control signals for controlling at least one of peak current and switching frequency operational parameters of the switched mode power converter; a constant voltage mode controller configured to process the sensed voltage input signal and generate a second plurality of output control signals for controlling at least one of the peak current and switching frequency operational parameters of the switched mode power converter; a primary peak current adjuster configured to process the primary current input signal, at least one of the first plurality of output control signals from the constant current mode controller, and at least one of the second plurality of output control signals from the constant voltage mode controller in order to configure the switch control signal to turn off the switch; and a switching frequency adjuster configured to process at least one of the first plurality of output control signals from the constant current mode controller and the second plurality of output signals from the constant voltage mode controller in order to configure the switch control signal to turn on the switch, wherein the controller is configured to enable the constant current mode controller if the second plurality of output control signals of the constant voltage mode controller represent an operation with peak current and switching frequency at maximum values, and a constant power mode of operation occurs during transitions to and from the constant current mode of operation and a constant voltage mode of operation, and both the constant voltage mode controller and the constant current mode controller control both the primary peak current adjuster and the switching frequency adjuster.