Dimming Control for Electronic Lamp

• US 20120091910A1
• Filed: 10/13/2011
• Published: 04/19/2012
• Est. Priority Date: 10/13/2010
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Zhang, Wanfeng, Pitigoi-Aron, Radu, Reed, Daniel
• Granted Patent: US 8,796,954 B2
• Time in Patent Office: Days
• US Class Current: 315/287
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/385 using flyback topology

Abstract

In one embodiment, an apparatus includes circuitry configured to receive a dimming input to control a dimming level of a lamp. Also, the apparatus includes circuitry configured to generate a control signal based on the dimming input. The control signal indicates the dimming level for a converter of the lamp and the converter is configured to interpret the control signal to control to the dimming level of the lamp using a sinusoidal signal.

Claims

1. An apparatus comprising:

circuitry configured to receive a dimming input to control a dimming level of a lamp; and

circuitry configured to generate a control signal based on the dimming input, wherein the control signal indicates the dimming level for a converter of the lamp, the converter configured to interpret the control signal to control to the dimming level of the lamp using a sinusoidal signal.

2. The apparatus of claim 1, wherein the circuitry configured to generate the control signal is further configured to modulate an input signal using a modulation signal that is generated based on the dimming input, the modulation signal including dimming information for the dimming level.

3. The apparatus of claim 2, wherein the modulation signal comprises a first time period in a line cycle including a sinusoidal waveform, wherein the converter uses characteristics of the first time period to determine the dimming level.

4. The apparatus of claim 1, wherein the control signal comprises a pattern based on a non-conduction angle to indicate a start signal.

5. The apparatus of claim 1, wherein the control signal comprises:

a first half of a line cycle having a non-conduction angle of a first value; and

a second half of the line cycle of the control signal having a non-conduction angle of a second value, wherein the first value and the second value indicate a start signal.

6. The apparatus of claim 5, wherein:

the line cycle is a first line cycle, and

the control signal comprises an off time in a second line cycle after the first line cycle, wherein the off time is used by the converter to determine the dimming level.

7. The apparatus of claim 5, wherein the off time is used to determine the non-conduction angle, wherein a ratio of the non-conduction angle in the first half or the second half of the first line cycle to the non-conduction angle of the second line cycle is used by the converter to determine the dimming level.

8. The apparatus of claim 1, wherein the lamp comprises an electronic lamp.

9. An apparatus comprising:

circuitry configured to receive a control signal based on a dimming input to control a dimming level of a lamp;

circuitry configured to interpret the control signal to determine the dimming level for a converter of the lamp; and

circuitry configured to control the dimming level of the lamp by adjusting a dimming level for a load of the lamp using a sinusoidal signal.

10. The apparatus of claim 9, wherein the circuitry configured to interpret the control signal is further configured to determine a modulation signal in the control signal, the modulation signal including dimming information for the dimming level.

11. The apparatus of claim 10, wherein the modulation signal comprises a first time period in a line cycle including a sinusoidal waveform, wherein the converter uses characteristics of the first time period to determine the dimming level.

12. The apparatus of claim 9, wherein the control signal comprises a pattern based on a non-conduction angle to indicate a start signal.

13. The apparatus of claim 9, wherein the control signal comprises:

a first half of a line cycle having a non-conduction angle of a first value; and

a second half of the line cycle of the control signal having a non-conduction angle of a second value, wherein the first value and the second value indicate a start signal.

14. The apparatus of claim 13, wherein:

wherein the line cycle is a first line cycle, and

the control signal comprises an off time in a second line cycle after the first line cycle, wherein the off time is used by the converter to determine the dimming level.

15. The apparatus of claim 13, wherein the off time is used to determine the non-conduction angle, wherein a ratio of the non-conduction angle in the first half or the second half of the first line cycle to the non-conduction angle of the second line cycle is used by the converter to determine the dimming level.

16. The apparatus of claim 9, wherein the lamp comprises an electronic lamp.

17. A method comprising:

receiving a dimming input to control a dimming level of a lamp; and

generating a control signal based on the dimming input, wherein the control signal indicates the dimming level for a converter of the lamp, the converter configured to interpret the control signal to control to the dimming level of the lamp using a sinusoidal signal.

18. The method of claim 17, wherein the control signal comprises an input signal that is modulated based on the dimming level or a start pattern in a first line cycle followed by a non-conduction angle in a second line cycle that is determined based on the dimming level.

19. A method comprising:

receiving a control signal based on a dimming input to control a dimming level of a lamp;

interpreting the control signal to determine the dimming level for a converter of the lamp; and

controlling the dimming level of the electronic lamp by adjusting a dimming level for a load of the lamp using a sinusoidal signal.

20. The method of claim 19, wherein the control signal comprises an input signal that is modulated based on the dimming level or a start pattern in a first line cycle followed by a non-conduction angle in a second line cycle that is determined based on the dimming level.