Driver for LED device, LED system, and adaptation method for LED device

Patent metadata

Field	Value
Publication number	US-12356522-B2
Application number	US-202418742042-A
Country	US
Kind code	B2
Filing date	Jun 13, 2024
Priority date	Sep 17, 2019
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

A driver and method for operating a driver circuit for a light-emitting diode (LED) device. In some embodiments, the driver circuit includes a rectifier operatively coupled to a ballast, a current regulator operatively coupled to the rectifier and to the LED device, and a detecting module operatively coupled to the LED device and to the current regulator. During a startup stage, the rectifier of the driver circuit rectifies direct current received from the ballast and provides the rectified current to the current regulator. The detecting module then detects a current through the LED device provided by the current regulator during the startup stage, wherein a value of the current through the LED device is a detecting indictor. The detecting module next provides the value of the current through the LED device to the current regulator which determines that it is outside a preset value range, converts the rectified current from the rectifier into a driving current having a value within the preset value range, and outputs the driving current to the LED device.

First claim

What is claimed is:

1. A method for operating a driver circuit for a light-emitting diode (LED) device, wherein the driver circuit comprises a rectifier operatively coupled to a ballast, a current regulator operatively coupled to the rectifier and to the LED device, and a detecting module operatively coupled to the LED device and to the current regulator, comprising:
rectifying, by the rectifier of the driver circuit during a startup stage, direct current received from the ballast and providing the rectified current to the current regulator;
detecting, by the detecting module of the driver circuit, a current through the LED device provided by the current regulator during the startup stage, wherein a value of the current through the LED device is a detecting indictor having a preset value range;
providing, by the detecting module, the value of the current through the LED device to the current regulator;
determining, by the current regulator, that the value of the current is outside the preset value range;
converting, by the current regulator, the rectified current from the rectifier into a driving current with a value within the preset value range; and
outputting, by the current regulator, the driving current to the LED device.

2. The method of claim 1 , wherein the LED device comprises an LED chip comprising a plurality of LEDs coupled in series, and the driving current is substantially equal to a rated current of the LED chip.

3. The method of claim 1 , wherein the LED device comprises N groups of LED chips, the N groups of LED chips are coupled in parallel with each other, each group comprises a plurality of LEDs coupled in series, and the driving current is substantially equal to N times a rated current of the LED chip, wherein N is a natural number equal to or larger than 2.

4. The method of claim 1 , further comprising directly transmitting, by the current regulator, rectified current from the rectifier to the LED device when the detected value of the current through the LED device is within the preset value range.

5. The method of claim 1 , wherein the current regulator comprises a current scaling module configured for scaling down direct current to a value equal to or less than a preset current threshold when the detected value of the current through the LED is not within the preset value range.

6. The method of claim 1 , wherein the current regulator comprises a constant-current control module configured for regulating the driving current to be substantially constant at the value equal to or less than a preset current threshold.

7. The method of claim 1 , wherein the detecting module comprises a sampling circuit for sampling the current through the LED device and a judging circuit for judging whether the current through the LED device is within the preset value range.

8. A driver for a light-emitting diode (LED) device comprising:
a rectifier operatively coupled to a ballast;
a current regulator operatively connected to the rectifier and to the LED device; and
a detecting module operatively coupled to the current regulator and to the LED device;
wherein the rectifier rectifies direct current received from the ballast and provides the rectified current to the current regulator during a startup stage,
the detecting module detects a current through the LED device provided by the current regulator during the startup stage, wherein a value of the current through the LED device is a detecting indictor having a preset value range, and provides the value of the current through the LED device to the current regulator, and
wherein, when the current regulator determines that the value of the current is outside the preset value range, the current regulator converts the rectified current from the rectifier into a driving current with a value within the preset value range, and outputs the driving current to the LED device.

9. The driver according to claim 8 , wherein the LED device comprises an LED chip comprising a plurality of LEDs coupled in series, and the driving current is substantially equal to a rated current of the LED chip.

10. The driver according to claim 8 , wherein the LED device comprises N groups of LED chips, the N groups of LED chips are coupled in parallel with each other, each group comprising a plurality of LEDs coupled in series, and the maximum current is substantially equal to N times a rated current of the LED chip, wherein N is a natural number equal to or larger than 2.

11. The driver according to claim 8 , wherein the current regulator directly transmits rectified current from the rectifier to the LED device when the detected value of the current through the LED device is within the preset value range.

12. The driver according to claim 8 , wherein the current regulator comprises a current scaling module configured for scaling down direct current to a value equal to or less than a preset current threshold when the detected value of the current through the LED is not within the preset value range.

13. The driver according to claim 8 , wherein the current regulator comprises a constant-current control module for regulating the drive current to be substantially constant at the value equal to or less than ae preset current threshold.

14. The driver according to claim 8 , wherein the detecting module comprises:
a sampling circuit for sampling the current through the LED device; and

a judging circuit for judging whether the current through the LED device is within the preset value range.

Assignees

• Savant Tech Llc

Inventors

• Zou Qiang
• Liu Zhichao
• Yan Qi

Classifications

• H05B45/305

  Frequency-control circuits · CPC title

• H05B45/345

  Current stabilisation; Maintaining constant current · CPC title

• H05B45/37 Primary

  Converter circuits · CPC title