Dimming edge detection for power converter

摘要

A controller for a power converter includes an edge detection circuit and a drive circuit. The edge detection circuit includes a comparator, a count module, and an edge checking module. The comparator is coupled to output a compare signal in response to comparing an input sense signal and a count signal. The input sense signal is representative of an input voltage of the power converter. The count module is coupled to adjust the count signal to track the input sense signal in response to receiving the compare signal. The edge checking module is coupled to output at least one edge signal in response to the compare signal. The drive circuit is coupled to output a drive signal in response to the at least one edge signal. The drive signal is for controlling a switch coupled to regulate an output of the power converter.

主权项

1. A controller for a power converter, the controller comprising:
an edge detection circuit including:
a comparator coupled to output a compare signal in response to comparing an input sense signal and a count signal, wherein the comparator gives the compare signal a first state when the input sense signal is below the count signal and gives the compare signal a second state when the input sense signal is above the count signal, the input sense signal representative of an input voltage of the power converter;a count module coupled to adjust the count signal to track the input sense signal in response to receiving the compare signal; andan edge checking module coupled to output at least one edge signal in response to the compare signal not changing between the first and the second state for a given time period; and a drive circuit coupled to output a drive signal in response to the at least one edge signal, wherein the drive signal is for controlling a switch coupled to regulate an output of the power converter.