Primary side voltage control in flyback converter

摘要

In one embodiment, an apparatus includes a sampling component. The sampling component receives a first voltage signal on a primary side of a transformer and monitors the first voltage signal to determine a voltage sampling time. The determined voltage sampling time is when the first voltage signal is used to estimate a second voltage level on a secondary side of the transformer. The first component further samples the first voltage signal at the voltage sampling time to determine a first voltage level. A second component outputs a control signal to control a switch to regulate the second voltage level based on the first voltage level.

主权项

1. An apparatus comprising:
a sampling component configured to:
receive a first voltage signal on a primary side of a transformer;detect a first time (T1) when the first voltage signal reaches a first level;detect a second time (T2) when the first voltage signal reaches a second level;determining a voltage sampling time according to the equation T1−2*(T2−T1), wherein the determined voltage sampling time is when the first voltage signal is used to estimate a second voltage level on a secondary side of the transformer; andsample the first voltage signal at the voltage sampling time to determine a first voltage level; a second component configured to output a control signal to control a switch to regulate the second voltage level based on the first voltage level.