Encoding device for light-emitting-diode lamp, lamp, and controlled lighting system

• US 20090261750A1
• Filed: 07/08/2008
• Published: 10/22/2009
• Est. Priority Date: 04/16/2008
• Status: Active Grant

• Current Assignee: Utada Technologies, LLC (Intellectual Ventures LLC)
• Original Assignee: Lite-On Electronics Company Limited (Lite-On Technology Corporation)
• Inventors: Hsueh, Hsiang-Chun, Tai, Horng-Ming
• Granted Patent: US 8,174,206 B2
• Time in Patent Office: Days
• US Class Current: 315/291
• CPC Class Codes: H05B 47/185 via power line carrier transmission

Abstract

A controlled lighting system includes an encoding device and a lamp. The encoding device includes a rectifier for rectifying an AC voltage input to result in a rectified signal, and an encoder for generating an encoded signal from the rectified signal and display data. The encoded signal has consecutive signal regions with a waveform of a positive half-cycle of an AC sinusoidal wave or a low potential. The lamp includes a LED unit and a decoding device. The decoding device includes a direct current converter for extracting a direct current voltage from the encoded signal, a detecting circuit for extracting a wave signal from the encoded signal, a processor for generating decoded data related to a light-emitting operation according to the wave signal, and a driver for driving the LED unit according to the direct current voltage from the direct current converter and the decoded data from the processor.

Claims

1. An encoding device for a light-emitting-diode (LED) lamp, said encoding device being adapted to receive an alternating current (AC) voltage input and display data related to a light-emitting operation, said encoding device comprising:

a rectifier for rectifying the AC voltage input to result in a rectified signal; and

an encoder for generating an encoded signal from the rectified signal and the display data, the encoded signal having an amplitude corresponding to a magnitude of the rectified signal, and a waveform corresponding to the display data, the encoded signal having a plurality of consecutive signal regions of equal time durations, each of the signal regions having one of first and second states, the waveform of the signal region having the first state being a positive half-cycle of an AC sinusoidal wave, the waveform of the signal region having the second state being a low potential waveform.

2. The encoding device as claimed in claim 1, wherein an amplitude of the rectified signal from said rectifier increases with an increase in an amplitude of the AC voltage input, and an amplitude of the signal regions of the encoded signal having the first state increases with an increase in the amplitude of the rectified signal.

3. The encoding device as claimed in claim 1, wherein, when the display data has a value of 1, the waveform of a corresponding one of the signal regions of the encoded signal has the first state, and when the display data has a value of 0, the waveform of a corresponding one of the signal regions of the encoded signal has the second state.

4. The encoding device as claimed in claim 1, wherein the rectified signal from said rectifier has a waveform that includes a plurality of consecutive regions of equal time durations, the waveform in each of the regions of the rectified signal being a positive half-cycle of the AC sinusoidal wave, said encoder selectively outputting the regions of the waveform of the rectified signal to result in the encoded signal.

5. The encoding device as claimed in claim 1, the display data including a plurality of bits, wherein said encoding device further comprises a zero-crossing detecting circuit for detecting zero voltage points in the AC voltage input and for generating a first trigger signal having a plurality of pulses corresponding to the zero voltage points, said encoder processing one of the bits of the display data each time one of the pulses of the first trigger signal is received thereby.

6. The encoding device as claimed in claim 5, wherein said encoder includes

a control circuit for selecting one of the first trigger signal and the low potential waveform for output as a control signal in accordance with the bit of the display data that is being processed, and

a switch controlled by the control signal such that the state of the waveform of one of the signal regions of the encoded signal corresponds to the bit of the display data that is being processed

7. The encoding device as claimed in claim 6, wherein said switch is a silicon-controlled rectifier.

8. The encoding device as claimed in claim 5, wherein said encoder includes

a control circuit for outputting a high potential waveform or a low potential waveform within a time period spanning two corresponding adjacent ones of the pulses of the first trigger signal as a control signal in accordance with the bit of the display data that is being processed, and

a switch controlled by the control signal such that the state of the waveform of one of the signal regions of the encoded signal corresponds to the bit of the display data that is being processed.

9. The encoding device as claimed in claim 8, wherein said switch is an enabler.

10. The encoding device as claimed in claim 1, further comprising a direct current regulator for regulating the rectified signal to result in a direct current voltage that is provided to said encoder.

11. A lamp adapted for receiving an encoded signal that includes a power component and a signal component related to a light-emitting operation, said lamp comprising:

a light-emitting-diode (LED) unit; and

a decoding device including

a direct current converter for extracting a direct current voltage from the encoded signal,

a detecting circuit for extracting a wave signal in digital form from the encoded signal,

a processor for generating decoded data related to a light-emitting operation of said LED unit in accordance with the wave signal extracted by said is detecting circuit, and

a driver for driving said LED unit according to the direct current voltage from said direct current converter and the decoded data from said processor.

12. The lamp as claimed in claim 11, wherein the decoded data from said processor is related to color to be emitted by said LED unit.

13. The lamp as claimed in claim 11, wherein said detecting circuit includes a zero-crossing detecting circuit for detecting zero voltage points in the encoded signal and for generating the wave signal according to the zero voltage points.

14. The lamp as claimed in claim 11, wherein said processor detects a level of the wave signal and generates recovered data according to a second trigger signal, said processor including an inverter for inverting the recovered data to obtain the decoded data.

15. The lamp as claimed in claim 11, wherein said decoding device further includes an isolating circuit for isolating noise from the encoded signal prior to receipt of the encoded signal by said direct current converter.

16. A controlled lighting system adapted to receive an alternating current (AC) voltage input and display data related to a light-emitting operation, said controlled lighting system comprising:

an encoding device including

a rectifier for rectifying the AC voltage input to result in a rectified signal, and

an encoder for generating an encoded signal from the rectified signal and the display data, the encoded signal having an amplitude corresponding to a magnitude of the rectified signal, and a waveform corresponding to the display data, the encoded signal having a plurality of consecutive signal regions of equal time durations, each of the signal regions having one of first and second states, the waveform of the signal region having the first state being a positive half-cycle of an AC sinusoidal wave, the waveform of the signal region having the second state being a low potential waveform; and

a lamp including a light-emitting-diode (LED) unit, and a decoding device including

a direct current converter for extracting a direct current voltage from the encoded signal,

a detecting circuit for extracting a wave signal in digital form from the encoded signal,

a processor for generating decoded data related to a light-emitting operation of said LED unit in accordance with the wave signal extracted by said detecting circuit, and

a driver for driving said LED unit according to the direct current voltage from said direct current converter and the decoded data from said processor.

17. The controlled lighting system as claimed in claim 16, wherein an amplitude of the rectified signal from said rectifier increases with an increase in an amplitude of the AC voltage input, and an amplitude of the signal regions of the encoded signal having the first state increases with an increase in the amplitude of the rectified signal.

18. The controlled lighting system as claimed in claim 16, wherein, when the display data has a value of 1, the waveform of a corresponding one of the signal regions of the encoded signal has the first state, and when the display data has a value of 0, the waveform of a corresponding one of the signal regions of the encoded signal has the second state.

19. The controlled lighting system as claimed in claim 16, wherein the rectified signal from said rectifier has a waveform that includes a plurality of consecutive regions of equal time durations, the waveform in each of the regions of the rectified signal being a positive half-cycle of the AC sinusoidal wave, said encoder selectively outputting the regions of the waveform of the rectified signal to result in the encoded signal.

20. The controlled lighting system as claimed in claim 16, the display data including a plurality of bits, wherein said encoding device further includes a zero-crossing detecting circuit for detecting zero voltage points in the AC voltage input and for generating a first trigger signal having a plurality of pulses corresponding to the zero voltage points, said encoder processing one of the bits of the display data each time one of the pulses of the first trigger signal is received thereby.

21. The controlled lighting system as claimed in claim 20, wherein said encoder includes

a control circuit for selecting one of the first trigger signal and the low potential waveform for output as a control signal in accordance with the bit of the display data that is being processed, and

a switch controlled by the control signal such that the state of the waveform of one of the signal regions of the encoded signal corresponds to the bit of the display data that is being processed.

22. The controlled lighting system as claimed in claim 21, wherein said switch is a silicon-controlled rectifier.

23. The controlled lighting system as claimed in claim 20, wherein said encoder includes

a control circuit for outputting a high potential waveform or a low potential waveform within a time period spanning two corresponding adjacent ones of the pulses of the first trigger signal as a control signal in accordance with the bit of the display data that is being processed, and

a switch controlled by the control signal such that the state of the waveform of one of the signal regions of the encoded signal corresponds to the bit of the display data that is being processed.

24. The controlled lighting system as claimed in claim 23, wherein said switch is an enabler.

25. The controlled lighting system as claimed in claim 16, wherein said encoding device further includes a direct current regulator for regulating the rectified signal to result in a direct current voltage that is provided to said encoder.

26. The controlled lighting system as claimed in claim 16, wherein the decoded data from said processor is related to color to be emitted by said LED unit.

27. The controlled lighting system as claimed in claim 16, wherein said detecting circuit includes a zero-crossing detecting circuit for detecting zero voltage points in the encoded signal and for generating the wave signal according to the zero voltage points.

28. The controlled lighting system as claimed in claim 16, wherein said processor detects a level of the wave signal and generates recovered data according to a second trigger signal, said processor including an inverter for inverting the recovered data to obtain the decoded data.

29. The controlled lighting system as claimed in claim 16, wherein said decoding device further includes an isolating circuit for isolating noise from the encoded signal prior to receipt of the encoded signal by said direct current converter.