Variable feedback signal based on conduction time

摘要

A controller for a power converter includes conduction detection circuitry and a variable reference generator. The conduction detection circuitry is coupled to generate a conduction signal representative of conduction times that an input signal is above a threshold value. The variable reference generator is coupled to receive the conduction signal and configured to generate a count value in response to a first conduction time of the conduction signal. The variable reference generator is coupled to output a reference signal in response to the count value and in response to prior count values stored in the variable reference generator.

主权项

1. A controller for a power converter, the controller comprising:
conduction detection circuitry coupled to generate a conduction signal representative of conduction times that an input signal is above a threshold value; and a variable reference generator coupled to receive the conduction signal and configured to generate a count value in response to a first conduction time of the conduction signal, wherein the variable reference generator is coupled to output a reference signal in response to the count value and in response to prior count values stored in the variable reference generator, the prior count values representative of prior conduction times of the conduction signal, and wherein the reference signal is for controlling a switch coupled to regulate an output of the power converter, wherein the variable reference generator includes:
averaging circuitry coupled to generate a central tendency value in response to the count value and a quantity of the prior count values; andupdate circuitry coupled to update a reference register with the central tendency value when the count value and a second quantity of the prior count values have either all been above or all been below a count reference value stored in the reference register.