LED driver and LED lighting device

摘要

An LED driver can include: a rectifying bridge configured to receive an AC current from an electrical ballast, and to generate a DC current; a rectifying and filtering circuit coupled to the rectifying bridge, and configured to rectify and filter the DC current, and to drive an LED load; a power switch coupled between an input of the rectifying and filtering circuit and ground, and configured to be controlled by a switching control signal; a first detecting circuit configured to sample a current that flows through the LED load, and to generate a first detection signal; a second detecting circuit configured to sample an output current of the rectifying bridge, and to generate a second detection signal; and a control circuit configured to generate the switching control signal according to the first and second detection signals.

主权项

1. A light-emitting diode (LED) driver, comprising:
a) a rectifying bridge configured to receive an AC current from an electrical ballast, and to generate a DC current; b) a rectifying and filtering circuit coupled to said rectifying bridge, and configured to rectify and filter said DC current, and to drive an LED load; c) a power switch coupled between an input of said rectifying and filtering circuit and ground, and configured to be controlled by a switching control signal such that said rectifying and filtering circuit is shorted when said power switch is turned on by said switching control signal; d) a first detecting circuit configured to sample a current that flows through said LED load, and to generate a first detection signal; e) a second detecting circuit configured to sample an output current of said rectifying bridge, and to generate a second detection signal; and f) a control circuit configured to generate said switching control signal according to said first and second detection signals.