Multiphase voltage sources driven AC—LED

• US 7,701,149 B2
• Filed: 11/28/2006
• Issued: 04/20/2010
• Est. Priority Date: 12/09/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Industrial Technology Research Institute
• Inventors: Lin, Ming-Te
• Primary Examiner(s): Vu; David Hung
• Assistant Examiner(s): Le; Tung X
• Application Number:
  US11/564,230
• Publication Number:
  US 20070133230A1
• Time in Patent Office: 1,239 Days
• Field of Search: 315/161, 315/169.3, 315/185.S, 315/185.R, 315/200.R, 315/312, 315/247, 315/291, 315/294, 315/297, 315/299, 315307-309, 362/227, 362/252, 362/800, 362/806, 362/812, 345/39, 345/46, 345/82
• US Class Current: 315/307
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback
• CPC Class Codes: H05B 45/31 Phase-control circuits
• CPC Class Codes: H05B 45/42 Antiparallel configurations

Abstract

Multiphase voltage sources are used in driving an AC_LED; different light timing is achieved by changing the relative phase or frequency of the voltage sources. Different light color mixing is also achieved when more than one AC_LED with different colors are combined to use.

Claims

1. A multiphase voltage sources driven AC_LED system, comprising:

a first AC_LED having a first terminal and a second terminal;

a multiphase voltage sources generator generating a first voltage with a first phase coupling to said first terminal and generating a second voltage with a second phase coupling to said second terminal;

a voltage phase controller coupling to said generator for controlling voltage phase of each voltage sources output therefrom; and

a feedback circuit having a first terminal and a second terminal, said first terminal coupling to said AC_LED, said second terminal coupling to said voltage phase controller.

2. The multiphase voltage sources driven AC_LED system as claimed in claim 1, further comprising a frequency adjustor coupling to said generator for controlling frequency of each of the voltage sources supplied to said AC_LED.

3. The multiphase voltage sources driven AC_LED system as claimed in claim 1, wherein the feedback circuit comprises a current feedback circuit having a first terminal and a second terminal, said first terminal coupling to each of said output voltage sources from said generator, said second terminal coupling to said voltage phase controller for controlling phase fluctuation limits of each voltage sources supplying to said AC_LED.

4. The multiphase voltage sources driven AC_LED system as claimed in claim 1, wherein the feedback circuit comprises a light feedback circuit having a first terminal and a second terminal, said first terminal coupling to light emission of said AC_LED, said second terminal coupling to said voltage phase controller for controlling the average light intensity or individual color intensity through adjusting the phase difference.

5. The multiphase voltage sources driven AC_LED system as claimed in claim 1, wherein the feedback circuit comprises a temperature feedback circuit having a first terminal and a second terminal, said first terminal coupling to said AC_LED to sense the temperature of the AC_LED, said second terminal coupling to said voltage phase controller to trigger an overheat protection mechanism.

6. The multiphase voltage sources driven AC_LED system as claimed in claim 1, further comprising a second AC_LED having a third terminal and a fourth terminal, said third terminal coupling to said first terminal, said generator generating a fourth voltage coupling to said fourth terminal.

7. The multiphase voltage sources driven AC_LED system as claimed in claim 6, further comprising a third AC_LED having a fifth terminal and a sixth terminal, said fifth terminal coupling to said second terminal, said sixth terminal coupling to said fourth terminal.

8. The multiphase voltage sources driven AC_LED system as claimed in claim 1, further comprising:

a second AC_LED having a third terminal and a fourth terminal; and

a third AC_LED having a fifth terminal and a sixth terminal;

wherein said third terminal and said fifth terminal are coupled to said second terminal, and said generator generates voltages supplied to said fourth terminal and said sixth terminal.

9. The multiphase voltage sources driven AC_LED system as claimed in claim 1, further comprising discrete light emitting diodes.

10. The multiphase voltage sources driven AC_LED system as claimed in claim 1, further comprising a plurality of DC_LEDs integrated into a single chip.

11. A multiphase voltage sources driven AC_LED system, comprising:

a first AC_LED, comprising;

a first node N1, a second node N2, a third node N3, a fourth node N4, said first node N1 and said third node N3 electrically coupling to a power source;

a first DC_LED electrically coupling from said first node N1 in forward direction to said second node N2;

a second DC_LED electrically coupling from said second node N2 in backward direction to said third node N3;

a third DC_LED electrically coupling from said third node N3 in backward direction to said fourth node N4;

a fourth DC_LED electrically coupling from said fourth node N4 in forward direction to said first node N1; and

a fifth DC_LED electrically coupling from said second node N2 in forward direction to said fourth node N4;

a multiphase voltage sources generator supplying a first voltage source having a first phase to said first node N1, and supplying a second voltage source having a second phase to the third node N3;

a voltage phase controller coupling to said generator for controlling voltage phase of each voltage sources output therefrom; and

a feedback circuit having a first terminal and a second terminal, said first terminal coupling to said AC_LED, said second terminal coupling to said voltage phase controller.

12. The AC_LED as claimed in claims 11, wherein said DC_LED is a discrete element.

13. The AC_LED as claimed in claims 11, wherein said DC_LED is disposed in a semiconductor chip.

14. A driven AC_LED formed with twelve DC_LEDs, comprising:

a first node N1, a second node N2, a third node N3, a fourth node N4, a fifth node N5, a sixth node N6, a seventh node N7, wherein said first node N1, said third node N3, and said fifth node N5 are coupled to a power source;

a first DC_LED coupling from said first node N1 in backward direction to said second node N2;

a second DC_LED coupling from said second node N2 in forward direction to said third node N3;

a third DC_LED coupling from said third node N3 in backward direction to said fourth node N4;

a fourth DC_LED coupling from said fourth node N4 in forward direction to said fifth node N5;

a fifth DC_LED coupling from said fifth node N5 in backward direction to said sixth node N6;

a sixth DC_LED coupling from said sixth node N6 in forward direction to said first node N1;

a seventh DC_LED coupling from said seventh node N7 in backward direction to said first node N1;

an eighth DC_LED coupling from said seventh node N7 in forward direction to said second node N2;

a ninth DC_LED coupling from said seventh node N7 in backward direction to said third node N3;

a tenth DC_LED coupling from said seventh node N7 in forward direction to said fourth node N4;

an eleventh DC_LED coupling from said seventh node N7 in backward direction to said fifth node N5; and

a twelfth DC_LED coupling from said seventh node N7 in forward direction to said sixth node N6.

15. A light timing controlling method for an AC_LED, comprising the steps of:

preparing an AC_LED having a first terminal and a second terminal;

preparing a multiphase voltage sources generator to generate a first voltage with a first phase and a second voltage with a second phase;

preparing a voltage phase controller to control said generator for controlling voltage phase of each voltage sources output therefrom;

preparing a feedback circuit having a first terminal and a second terminal;

coupling said first terminal of the feedback circuit to the AC_LED; and

coupling said second terminal of the feedback circuit to said voltage phase controller;

coupling said first voltage to said first terminal of the AC_LED; and

coupling said second voltage to said second terminal of the AC_LED.

16. The light timing controlling method for an AC_LED as claimed in claim 15, wherein said AC_LED further comprises a third terminal and couples a third voltage source with a third phase to said third terminal.

17. The light timing controlling method for an AC_LED as claimed in claim 16, wherein said AC_LED further comprises a fourth terminal and couples a fourth voltage source with a fourth phase to said fourth terminal.

18. The light timing controlling method for an AC_LED as claimed in claim 15, further comprising the step of changing frequency of each of said voltage sources.

19. The light timing controlling method for an AC_LED as claimed in claim 15, wherein said voltage having a waveform selected from the group consisting of a sine waveform, a triangle waveform, and a characterized waveform.