Importance

Loading Importance Indicators...

Abstract

An LED tube lamp is provided. The LED tube lamp includes a lamp tube having a first pin and a second pin at a first end of the lamp tube and a third pin and a fourth pin at a second end of the lamp tube, for receiving an external driving signal; a light strip disposed in the lamp tube, comprising an LED module for emitting light; a rectifying circuit for rectifying the external driving signal to produce a rectified signal; a filtering circuit coupled to the rectifying circuit, for filtering the rectified signal in order to drive the LED module; a current-limiting element for receiving the external driving signal input at one or more of the pins, the current-limiting element coupled to one or more of the pins, and coupled to the rectifying circuit; and a ballast interface circuit coupled to or in the rectifying circuit, and coupled to the current-limiting element, for the LED tube lamp to be compatible with a ballast providing the external driving signal, wherein the ballast interface circuit has a first terminal and a second terminal and is configured to determine whether the external driving signal is output from a ballast, according to a state of a property of the external driving signal, or according to a state of a property of a detection signal transmitted through the first terminal and the second terminal upon the external driving signal being input to the LED tube lamp.

First Claim