CN-118524604-B - Lighting device with reverse voltage clamp release mechanism

CN118524604BCN 118524604 BCN118524604 BCN 118524604BCN-118524604-B

Abstract

A lighting device with a reverse voltage clamp release mechanism comprises a current-limiting diode, a plurality of light-emitting diodes, a rectifier and a power input end. The light emitting diodes are connected in series to form a series circuit, and the series circuit is connected in parallel with the current limiting diode. Each light emitting diode has a parasitic capacitance. The rectifier is connected with the plurality of light emitting diodes. The power input end is connected with an external power supply and a rectifier. The current-limiting diode forms a discharge loop, and the discharge current generated by the parasitic capacitance discharge of each LED is released through the discharge loop.

Inventors

ZHANG BAIHAO
LIN ZHIRONG
LU FUXING

Assignees

厦门普为光电科技有限公司

Dates

Publication Date: 20260508
Application Date: 20240430

Claims (9)

1. A lighting device having a reverse voltage clamp release mechanism, comprising: a current limiting diode; A plurality of light emitting diodes connected in series with each other to form a series circuit, the series circuit being connected in parallel with the current limiting diodes, each of the light emitting diodes having a parasitic capacitance; a rectifier connected to the plurality of light emitting diodes; The power input end is connected with an external power supply and the rectifier; a storage capacitor connected with the LEDs, and The converter is connected with the rectifier, the energy storage capacitor and the grounding point; The current-limiting diodes form a discharge loop, the parasitic capacitance of each light-emitting diode is continuously charged and discharged when the connection between the power input end and an external power supply is cut off, and the discharge current generated by the discharge of the parasitic capacitance of each light-emitting diode is released through the discharge loop, so that the discharge current enters a grounding point through the current-limiting diodes, the energy storage capacitor and the converter, and the voltage drop formed by the conduction of the current-limiting diodes is smaller than the reverse voltage bearable by the series circuit, so that a reverse voltage clamping release mechanism is achieved.
2. The lighting device with reverse voltage clamp release mechanism of claim 1, wherein said discharge current of each of said light emitting diodes passes through said current limiting diode, said storage capacitor and said inverter into said ground point.
3. The lighting device with reverse voltage clamp release mechanism of claim 1, wherein each of said light emitting diodes has a junction capacitance, said junction capacitance being in parallel with said light emitting diode.
4. The lighting device with reverse voltage clamp release mechanism of claim 1, further comprising a filter capacitor, said rectifier being connected to said converter through said filter capacitor.
5. The lighting device with an inverse voltage clamp release mechanism of claim 1, wherein the converter is a boost converter, a buck converter, or a boost/buck converter.
6. The lighting device with reverse voltage clamp release mechanism of claim 1, wherein said power supply input comprises a hot wire input and a neutral wire input.
7. The lighting device with reverse voltage clamp release mechanism of claim 1, wherein said rectifier is a full wave rectifier.
8. The lighting device with an inverse voltage clamp release mechanism of claim 1, wherein the rectifier is a half-wave rectifier.
9. The lighting device with reverse voltage clamp release mechanism of claim 1, wherein the external power source is mains.

Description

Lighting device with reverse voltage clamp release mechanism Technical Field The present invention relates to a lighting device, and more particularly, to a lighting device with a reverse voltage clamp release mechanism. Background The existing lighting device commonly adopts a metal shell to achieve better heat dissipation, and meanwhile, the metal shell is grounded to meet the safety requirements. Therefore, parasitic capacitance is formed between the light source plate of the lighting device and the housing metal profile. Generally, a user switches on or off the lighting device by switching on one of the live and neutral inputs of the lighting device. Thus, an ac voltage difference is generated between the light source board and the metal case. The parasitic capacitor is still charged and discharged after the lighting device is turned off due to the characteristic that the capacitor is connected with alternating current and is isolated from direct current. Therefore, the reverse voltage generated by the parasitic capacitance is applied to each light source on the light source board, so that the lighting device is easy to damage after a period of use. Manufacturers of lighting devices have also proposed several solutions to solve the above-mentioned problems. The first solution is to add a zener diode to the light source, but this solution results in increased cost and reduced light efficiency. The second solution is to use an isolated power supply, but this approach results in reduced power efficiency and increased cost. A third solution is to incorporate resistors or capacitors on the light source, but this solution results in increased cost and reduced light efficiency. A fourth solution is to optimize the layout of the circuit board to change the parasitic capacitance, but this solution requires a higher production process. Disclosure of Invention According to an embodiment of the present invention, a lighting device with an inverse voltage clamp release mechanism is provided, which includes a current-limiting diode, a plurality of light-emitting diodes, a rectifier, and a power input terminal. The light emitting diodes are connected in series to form a series circuit, and the series circuit is connected in parallel with the current limiting diode. Each light emitting diode has a parasitic capacitance. The rectifier is connected with the plurality of light emitting diodes. The power input end is connected with an external power supply and a rectifier. The current-limiting diode forms a discharge loop, and the discharge current generated by the parasitic capacitance discharge of each LED is released through the discharge loop. In an embodiment, the lighting device further comprises a converter and a storage capacitor. The rectifier is connected with the converter. The converter is connected with the energy storage capacitor and the grounding point. The energy storage capacitor is connected with the light emitting diodes. In one embodiment, the discharge current of each led is passed through the current limiting diode, the storage capacitor and the inverter to the ground. In one embodiment, each light emitting diode has a junction capacitance connected in parallel with the light emitting diode. In an embodiment, the lighting device further comprises a filter capacitor. The rectifier is connected with the converter through a filter capacitor. In an embodiment, the converter is a boost converter, a buck converter, or a boost/buck converter. In one embodiment, the power input includes a hot input and a neutral input. In one embodiment, the rectifier is a full wave rectifier. In one embodiment, the rectifier is a half-wave rectifier. In one embodiment, the external power source is a mains supply. As described above, the lighting device with the reverse voltage clamp release mechanism according to the embodiments of the present invention may have one or more of the following advantages: (1) In an embodiment of the invention, the lighting device includes a current-limiting diode, a plurality of light emitting diodes, a rectifier and a power input terminal. The light emitting diodes are connected in series to form a series circuit, and the series circuit is connected in parallel with the current limiting diode. Each light emitting diode has a parasitic capacitance. The rectifier is connected with the plurality of light emitting diodes. The power input end is connected with an external power supply and a rectifier. The current-limiting diode forms a discharge loop, and the discharge current generated by the parasitic capacitance discharge of each LED is released through the discharge loop, so as to realize a reverse voltage clamp release mechanism. By the reverse voltage clamp release mechanism, the plurality of light emitting diodes cannot be damaged by reverse voltage, so that the reliability of the lighting device is improved. (2) In one embodiment of the present invention, the current limiting diode of the