LED driver with advanced dimming

• US 9,655,179 B2
• Filed: 05/04/2016
• Issued: 05/16/2017
• Est. Priority Date: 05/04/2015
• Status: Active Grant

• Current Assignee: LEDVANCE LLC (MLS Co. Ltd.)
• Original Assignee: TerraLUX Incorporated
• Inventors: Brandt, Brian Eldin
• Primary Examiner(s): TRAN, THUY V
• Application Number:
  US15/146,757
• Publication Number:
  US 20160330808A1
• Time in Patent Office: 377 Days
• Field of Search: 315209 R, 315247, 315291, 315307, 315308, 315185 R
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/18 using temperature feedback
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/375 using buck topology
• CPC Class Codes: H05B 45/382 with galvanic isolation between input and output

Abstract

This disclosure describes systems, methods, and apparatus for an LED driver circuit capable of responding to dimmer signals from three different types of dimmers: a phase cut dimmer, a dedicated dimmer (e.g., 0-10V dimmer), and a button dimmer. The processor can include inputs for each of these dimmer types, and can be configured to determine which of the three types of dimmers is controlling the LED driver circuit, and determine which dimming signals to respond to when more than one dimmer type is trying to control the LED.

Claims

1. An LED driver circuit, the LED driver circuit comprising:

an AC mains connection;

one or more power conversion components including at least a constant current source for driving one or more LEDs;

a phase cut detection component configured to monitor for a phase cut voltage on the AC mains connection;

a dedicated dimmer input configured to monitor for a dedicated dimming voltage from a dedicated dimmer;

a button dimming input configured to monitor for a button dimming signal from a button dimmer;

a processor with one or more processing components, the processor coupled to the phase cut detection component, the dedicated dimmer input, and the button dimming input; and

a memory having non-transitory, tangible processor executable code stored on the memory that when executed on the processor causes the processor to;

control the constant current source based on the phase cut voltage, the dedicated dimming voltage, the button dimming signal, or a combination of the dedicated dimming voltage and the button dimming signal;

ignore signals at the button dimmer input if the processor is in a lockout mode; and

to enter or exit the lockout mode upon detecting (1) interaction with the button dimmer longer than a first threshold time or (2) a plurality of switch toggles occurring within a second threshold time.

2. The LED driver circuit of claim 1, wherein the dedicated dimmer input is selected from the group consisting of:

a 0-10V dimmer input;

a pulse-width modulation (PWM) dimmer input; and

a digital addressable lighting interface (DALI) dimmer input.

3. The LED driver circuit of claim 1, wherein the button dimmer includes a button, switch, or a touch-sensitive interface and wherein the button dimmer can be coupled to the LED driver circuit or remote from the LED driver circuit.

4. The LED driver circuit of claim 1, wherein the non-transitory, tangible processor executable code, is executable on the processor to cause the processor to determine whether the phase cut dimmer, the dedicated dimmer, or the button dimmer is coupled to the LED driver circuit and trying to control a brightness of the one or more LEDs, and if more than one of these dimmers is coupled to the LED driver circuit and attempting to control the brightness of the one or more LEDs, then:

disabling dedicated dimming and button dimming when there is phase cut dimming; and

allowing button dimming when there is dedicated dimming and no phase cut dimming.

5. The LED driver circuit of claim 4, wherein when the dedicated dimmer and the button dimmer are both coupled to the LED driver circuit, the button dimming controls a range of the brightness of the one or more LEDs, and the dedicated dimmer controls the brightness within the range.

6. The LED driver circuit of claim 5, wherein the non-transitory, tangible processor executable code, is executable on the processor to cause the processor to reset the range of brightness of the one or more LEDs when the brightness is at a minimum LED brightness and the button dimmer is further activated.

7. The LED driver circuit of claim 4, wherein the button dimming mode is the default mode of the processor when no other dimming signals are detected.

8. The LED driver circuit of claim 4, wherein the non-transitory, tangible processor executable code, is executable on the processor to cause the processor to monitor for a dedicated dimming signal when the processor is in the button dimming mode.

9. The LED driver circuit of claim 1, wherein the processor is a microcontroller.

10. The LED driver circuit of claim 9, wherein the memory is part of the microcontroller.

11. The LED driver circuit of claim 1, wherein the LED driver circuit is either a single-stage or two-stage LED driver.

12. The LED driver circuit of claim 1, wherein the dedicated dimmer input and the button dimming input are part of the processor.

13. A method of operating an LED driver circuit, the method comprising:

monitoring a phase of an AC mains signal for a phase cut dimming signal, the AC mains signal providing power to the LED driver circuit;

monitoring a dedicated dimming input for a dedicated dimming signal;

monitoring a button dimming input for a button dimming signal;

determining whether a phase cut dimmer, a dedicated dimmer, a button dimmer, or some combination of these is attempting to control the LED brightness;

controlling a constant current source of the LED driver circuit based on the phase cut voltage, the dedicated dimming voltage, the button dimming signal, or a combination of the dedicated dimming voltage and the button dimming signal;

ignoring the button dimmer signal if the LED driver circuit is in a lockout mode; and

wherein the LED driver circuit enters or exits the lockout mode upon detecting (1) interaction with a button dimmer longer than a first threshold time or (2) a plurality of switch toggles occurring within a second threshold time.

14. The method of claim 13, wherein the dedicated dimming signal is a 0-10V signal, a pulse-width modulated (PWM) signal, or a digital addressable lighting interface (DALI) signal.

15. The method of claim 13, wherein the button dimming signal is generated by a button dimmer, switched dimmer, or a touch-sensitive interface dimmer.

16. The method of claim 13, wherein when two or more dimmer signals are detected:

disabling the dedicated dimming mode and the button dimming mode when there is phase cut dimming; and

allowing the button dimming mode when there is dedicated dimming and no phase cut dimming.

17. The method of claim 16, wherein when dedicated dimming and button dimming are both enabled, the button dimming controls a range of LED brightness, and the dedicated dimming controls the LED brightness within the range.

18. A non-transitory, tangible processor readable storage medium, encoded with processor readable code for controlling an LED driver circuit comprising:

monitoring a phase of an AC mains signal for a phase cut dimming signal, the AC mains signal providing power to the LED driver circuit;

monitoring a dedicated dimming input for a dedicated dimming signal;

monitoring a button dimming input for a button dimming signal;

determining whether a phase cut dimmer, a dedicated dimmer, a button dimmer, or some combination of these is attempting to control an LED brightness;

controlling a constant current source of the LED driver circuit based on the phase cut voltage, the dedicated dimming voltage, the button dimming signal, or a combination of the dedicated dimming voltage and the button dimming signal;

disabling the dedicated dimming mode and the button dimming mode when there is phase cut dimming; and

allowing the button dimming mode when there is dedicated dimming and no phase cut dimming.

19. The non-transitory, tangible processor readable storage medium of claim 18, wherein the dedicated dimming signal is a 0-10V signal, a pulse-width modulated (PWM) signal, or a digital addressable lighting interface (DALI) signal.

20. The non-transitory, tangible processor readable storage medium of claim 18, wherein the button dimming signal is generated by a button dimmer, switched dimmer, or a touch-sensitive interface dimmer.

21. The non-transitory, tangible processor readable storage medium of claim 18, further comprising ignoring the button dimmer signal if the LED driver circuit is in a lockout mode.

22. The non-transitory, tangible processor readable storage medium of claim 21, wherein the LED driver circuit enters or exits the lockout mode upon detecting (1) interaction with a button dimmer longer than a first threshold time or (2) a plurality of switch toggles occurring within a second threshold time.

23. The non-transitory, tangible processor readable storage medium of claim 18, wherein when dedicated dimming and button dimming are both enabled, the button dimming controls a range of LED brightness, and the dedicated dimming controls the LED brightness within the range.

24. A method of operating an LED driver circuit, the method comprising:

monitoring a phase of an AC mains signal for a phase cut dimming signal, the AC mains signal providing power to the LED driver circuit;

monitoring a dedicated dimming input for a dedicated dimming signal;

monitoring a button dimming input for a button dimming signal;

determining whether a phase cut dimmer, a dedicated dimmer, a button dimmer, or some combination of these is attempting to control the LED brightness;

controlling a constant current source of the LED driver circuit based on the phase cut voltage, the dedicated dimming voltage, the button dimming signal, or a combination of the dedicated dimming voltage and the button dimming signal;

disabling the dedicated dimming mode and the button dimming mode when there is phase cut dimming; and

allowing the button dimming mode when there is dedicated dimming and no phase cut dimming.

25. The method of claim 24, further comprising ignoring the button dimmer signal if the LED driver circuit is in a lockout mode and wherein the LED driver circuit enters or exits the lockout mode upon detecting (1) interaction with a button dimmer longer than a first threshold time or (2) a plurality of switch toggles occurring within a second threshold time.

26. The method of claim 24, wherein the dedicated dimming signal is a 0-10V signal, a pulse-width modulated (PWM) signal, or a digital addressable lighting interface (DALI) signal.

27. The method of claim 24, wherein the button dimming signal is generated by a button dimmer, switched dimmer, or a touch-sensitive interface dimmer.

28. The method of claim 24, wherein when two or more dimmer signals are detected:

disabling the dedicated dimming mode and the button dimming mode when there is phase cut dimming; and

allowing the button dimming mode when there is dedicated dimming and no phase cut dimming.

29. The method of claim 28, wherein when dedicated dimming and button dimming are both enabled, the button dimming controls a range of LED brightness, and the dedicated dimming controls the LED brightness within the range.