LED tube lamp
An LED tube lamp comprises a glass tube, two end caps, an LED light strip inside the glass tube, a plurality of LED light sources on the LED light strip, a power supply module and an adhesive. The glass tube comprises a main body has an outer surface and two rear end regions respectively at two ends of the main body. The outer diameter of each of the rear end regions is less than that of the main body. Each of the end caps comprises a tubular wall sleeving over the respective rear end region and an end wall substantially perpendicular to the axial direction of the tubular wall and connected to an end of the tubular wall. The diameter of the outer surface of the main body is substantially the same as the diameter of the outer surface of the tubular wall. The power supply, comprises a rectifying circuit and a filtering circuit, is configured to drive the plurality of LED light sources. The adhesive is disposed between each of the inner surface of the tubular wall and the outer surface of each of the rear end regions.
1. An LED tube lamp, comprising:
a glass tube, comprising:
a main body with an outer surface; and
two rear end regions respectively at two ends of the main body, wherein an outer diameter of each of the rear end regions is less than the diameter of the main body;
two end caps respectively sleeving over the two rear end regions, each of the end caps comprising:
a tubular wall substantially coaxial with the glass tube and sleeving over the respective rear end region, the tubular wall comprising an inner surface and an outer surface, wherein the diameter of the outer surface of the main body is substantially the same as the diameter of the outer surface of the tubular wall; and
an end wall substantially perpendicular to the axial direction of the tubular wall and connected to an end of the tubular wall away from the glass tube;
an LED light strip disposed inside the glass tube and attached to an inner circumferential surface of the glass tube;
a plurality of LED light sources mounted on the LED light strip;
a power supply module electrically connecting the plurality of LED light sources and configured to drive the plurality of LED light sources; and
an adhesive disposed between each of the inner surface of the tubular wall and the outer surface of each of the rear end regions,
wherein the power supply module at least comprises a rectifying circuit and a filtering circuit, the filtering circuit is coupled to the rectifying circuit and the plurality of LED light sources;
wherein the power supply module comprises a printed circuit board, the circuit board comprises a first surface and a second surface opposite to and substantially parallel with the first surface, and the first surface and the second surface of the circuit board are substantially parallel with the axial direction of the tubular wall, further wherein the printed circuit board comprises two soldering pads arranged on the first surface thereof, the printed circuit board electrically connecting to the LED light strip via the two soldering pads.
2. The LED tube lamp of claim 1 , wherein the printed circuit board is stacked with an end of the LED light strip.
3. The LED tube lamp of claim 2 , wherein the printed circuit board is stacked with an end of the LED light strip in one of the rear end regions.
4. The LED tube lamp of claim 1 , wherein the rectifying circuit comprises four rectifying diodes configured to full-wave rectify a received signal and generate a rectified signal.
5. The LED tube lamp of claim 4 , wherein the filtering circuit is configured to generate a filtered signal based on the rectified signal and comprises:
a first capacitor, having an end electrically connected to the rectifying circuit to receive the rectified signal;
a first inductor, having an end electrically connected to the end of the first capacitor; and
a second capacitor, having an end electrically connected to another end of the first inductor, and having another end electrically connected to another end of the first capacitor.
6. The LED tube lamp of claim 5 , wherein the power supply module further comprises:
a driving circuit, electrically connected to the filtering circuit to receive the filtered signal and perform power conversion for converting the filtered signal into a driving signal at driving output terminals electrically connected to the LED light strip.
7. The LED tube lamp of claim 6 , wherein the driving circuit comprises:
a switch, having a first terminal, a second terminal, and a control terminal;
a controller, electrically connected to the control terminal for controlling current conduction between the first and second terminals;
a second inductor, having an end electrically connected to the first terminal of the switch, and another end electrically connected to one of the driving output terminals; and
a diode, having an anode electrically connected to the end of the second inductor, and a cathode electrically connected to another one of the driving output terminals.
8. The LED tube lamp of claim 7 , wherein the power supply module further comprises:
an anti-flickering circuit, electrically connected between the filtering circuit and the driving circuit and configured to consume partial energy of the filtered signal so as to reduce ripples of the filtered signal.
9. The LED tube lamp of claim 8 , wherein the anti-flickering circuit comprises at least a resistor electrically connected between output terminals of the filtering circuit.
10. An LED tube lamp, comprising:
a glass tube, comprising:
a main body having a first outer surface and a first inner surface; and
two rear end regions respectively at two ends of the main body;
two end caps respectively sleeving over the two rear end regions, each of the end caps comprising:
a tubular wall substantially coaxial with the glass tube and sleeving over the respective rear end region, the tubular wall comprising a second outer surface and a second inner surface, wherein the diameter of the first outer surface of the main body is substantially the same as the diameter of the second outer surface of the tubular wall; and
an end wall substantially perpendicular to the axial direction of the tubular wall and connected to an end of the tubular wall away from the glass tube;
an LED light strip disposed inside the glass tube and attached to an inner circumferential surface of the glass tube;
a plurality of LED light sources mounted on the LED light strip;
a power supply module electrically connecting the plurality of LED light sources and configured to drive the plurality of LED light sources;
a diffusive layer covered on the first outer surface or the first inner surface of the main body; and
an adhesive disposed between the second inner surface of one of the tubular wall and the corresponding outer surface of the rear end region,
wherein the power supply module at least comprises a rectifying circuit and a filtering circuit, the filtering circuit is coupled to the rectifying circuit;
wherein the power supply module comprises a printed circuit board, the circuit board comprises a first surface and a second surface opposite to and substantially parallel with the first surface, and the first surface and the second surface of the circuit board are substantially parallel with the axial direction of the tubular wall, further wherein the printed circuit board comprises two soldering pads arranged on the first surface thereof, the printed circuit board electrically connecting to the LED light strip via the two soldering pads.
11. The LED tube lamp of claim 10 , wherein the printed circuit board is stacked with an end of the LED light strip.
12. The LED tube lamp of claim 11 , wherein the printed circuit board is stacked with an end of the LED light strip in one of the rear end regions.
13. The LED tube lamp of claim 11 , wherein the LED light strip is directly soldered to the two soldering pads.
14. The LED tube lamp of claim 11 , wherein the power supply module comprises at least one of a transistor and an integrated circuit mounted on the second surface of the printed circuit board.
15. The LED tube lamp of claim 14 , wherein the rectifying circuit has a first input terminal electrically connected to a first pin disposed on one of the two end caps and a second input terminal electrically connected to a second pin disposed on the other one of the two end caps, and the rectifying circuit produces a rectified signal between a first rectifying output terminal and a second rectifying output terminal.
16. The LED tube lamp of claim 15 , wherein the rectifying circuit comprises:
a first rectifying diode, having an anode connected to the second rectifying output terminal and a cathode connected to the second input terminal;
a second rectifying diode, having an anode connected to the second rectifying output terminal and a cathode connected to the first input terminal;
a third rectifying diode, having an anode connected to the second input terminal and a cathode connected to the first output terminal; and
a fourth rectifying diode, having an anode connected to the first input terminal and a cathode connected to the first output terminal.
17. The LED tube lamp of claim 16 , wherein the filtering circuit further comprises:
a first filtering unit, electrically connected to the first and the second rectifying output terminals to receive the rectified signal, and configured to produce a filtered signal.
18. The LED tube lamp of claim 17 , wherein the first filtering unit comprises:
a first capacitor, having an end electrically connected to the first rectifying output terminal and the other end electrically connected to the second rectifying output terminal.
19. The LED tube lamp as claimed in claim 18 , wherein the filtering circuit further comprises:
a second filtering unit, electrically connected between the first input terminal and the pin electrically connected to the first input terminal.
20. The LED tube lamp of claim 19 , wherein the second filtering unit comprises:
an inductor, having an end connected to the pin disposed on one of the two end caps and the other end connected to the first input terminal.
21. The LED tube lamp of claim 19 , wherein the filtering circuit further comprises:
a third filtering unit, electrically connected between one of the pins and one of the rectifying diodes of the rectifying circuit.
22. The LED tube lamp of claim 21 , wherein the third filtering unit comprises:
an EMI-reducing capacitor, connected between the pin disposed on one of the two end caps and the anode of the third rectifying diode.
23. The LED tube lamp of claim 18 , wherein the power supply module further comprises:
a driving circuit, electrically connected to the first filtering unit to receive the filtered signal and configured to perform power conversion for converting the filtered signal into a driving signal,
wherein the LED light sources receive the driving signal from driving output terminals for emitting light.
24. The LED tube lamp of claim 23 , wherein the driving circuit comprises:
a controller;
a switch, having a first terminal electrically connected to the end of the first capacitor, a second terminal, and a control terminal coupled to the controller, wherein the switch is turned on or off in response to a signal received from the controller;
a diode, having an anode electrically connected to the other end of the first capacitor and a cathode electrically connected to the second terminal of the switch;
an inductor, having an end electrically connected to the second terminal of the switch, and another end electrically connected to the LED light sources via one of the driving output terminals; and
a second capacitor, having an end electrically connected to the another end of the inductor and the other end electrically connected to the LED light sources via the other one of the driving output terminals.
25. The LED tube lamp of claim 14 , wherein the rectifying circuit comprises four rectifying diodes configured to full-wave rectify a received signal and generate a rectified signal.
26. The LED tube lamp of claim 25 , wherein the filtering circuit is configured to generate a filtered signal based on the rectified signal and comprises:
a first capacitor, having an end electrically connected to the rectifying circuit to receive the rectified signal.
27. The LED tube lamp of claim 26 , wherein the filtering circuit further comprises:
a second capacitor, electrically connected between input terminals of the rectifying circuit.
28. The LED tube lamp of claim 27 , wherein the power supply module further comprises:
a driving circuit, electrically connected to the filtering circuit to receive the filtered signal and perform power conversion for converting the filtered signal into a driving signal at driving output terminals electrically connected to the LED light strip.
29. The LED tube lamp of claim 28 , wherein the driving circuit comprises:
the transistor, having a first terminal, a second terminal and a control terminal;
the integrated circuit, electrically connected to the control terminal for controlling current conduction between the first and the second terminals;
an inductor, having an end electrically connected to the first terminal of the switch, and another end electrically connected to one of the driving output terminals; and
a diode, having an anode electrically connected to the end of the inductor, and a cathode electrically connected to another one of the driving output terminals.
30. The LED tube lamp of claim 29 , wherein the driving circuit further comprises:
a third capacitor, electrically connected between the driving output terminals.