DRIVING CIRCUIT AND LAMPS

• US 20130093349A1
• Filed: 10/18/2012
• Published: 04/18/2013
• Est. Priority Date: 10/18/2011
• Status: Active Grant

• Current Assignee: Lextar Electronics Corporation
• Original Assignee: Lextar Electronics Corporation
• Inventors: Chen, Chun-Kuang, Chen, Po-Shen, Lin, Feng-Ling, Chen, Hui-Ying, Chen, Tung-Yu
• Granted Patent: US 9,560,701 B2
• Time in Patent Office: Days
• US Class Current: 315/250
• CPC Class Codes: H02M 1/008 Plural converter units for generating at two or more independent and non-parallel outputs, e.g. systems with plural point of load switching regulators
• CPC Class Codes: H02M 7/05 Capacitor coupled rectifiers
• CPC Class Codes: H02M 7/064 with several outputs
• CPC Class Codes: H05B 47/00 Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

The invention relates to a driving circuit comprising a first bridge circuit, a second bridge circuit, a first protection device and a second protection device. The first bridge circuit comprising a first positive input terminal, a first negative input terminal, a first positive output terminal and a first negative output terminal is coupled to an AC voltage source to output a first voltage. The second bridge circuit comprising a second positive input terminal, a second negative input terminal, a second positive output terminal and a second negative output terminal is coupled to the AC voltage source to output a second voltage. The second and the first negative output terminals are both coupled to the ground potential. The first protection device is coupled between the second positive input terminal and the AC voltage source. The second protection device is coupled between the second negative input terminal and the AC voltage source.

Claims

1. A driving circuit, comprising:

a first bridge circuit, wherein the first bridge circuit is coupled to an AC voltage source to output a first voltage, and the first bridge circuit comprises a first positive input terminal, a first negative input terminal, a first positive output terminal and a first negative output terminal;

a second bridge circuit, wherein the second bridge circuit is coupled to the AC voltage source to output a second voltage, and the second bridge circuit comprises a second positive input terminal, a second negative input terminal, a second positive output terminal and a second negative output terminal, wherein the second negative output terminal and the first negative output terminal are coupled to the same ground potential;

a first protection device coupled between the second positive input terminal and the AC voltage source; and

a second protection device coupled between the second negative input terminal and the AC voltage source.

2. The driving circuit of claim 1, wherein the first bridge circuit is coupled to a first load, the second bridge circuit is coupled to a second load, and a first impedance value of the first load is greater than a second impedance value of the second load.

3. The driving circuit of claim 1, wherein the first protection device comprises a first capacitor and a first diode.

4. The driving circuit of claim 3, wherein a power of the second bridge circuit is limited by the capacitance of the first capacitor and the capacitance of a second capacitor of the second protection device.

5. The driving circuit of claim 1, wherein the second protection device comprises a second capacitor and a second diode.

6. The driving circuit of claim 1, wherein the first protection device and the second protection device form a non-polarized protection device.

7. The driving circuit of claim 6, wherein the non-polarized protection device comprises:

a first capacitor comprising a first anode and a first cathode;

a second capacitor comprising a second anode and a second cathode coupled to the first cathode;

a first diode comprising a third anode and a third cathode, wherein the third anode is coupled to the first cathode, and the third cathode is coupled to the first anode; and

a second diode comprising a fourth anode and a fourth cathode, wherein the fourth anode is coupled to the second cathode, and the fourth cathode is coupled to the second anode.

8. The driving circuit of claim 1, wherein the first protection device and the second protection device are configured for avoiding that an input current inputted from the first positive input terminal or the first negative input terminal of the first bridge circuit is fed back to the second positive input terminal or the second negative input terminal of the second bridge circuit.

9. A lamp, comprising:

a driving circuit, comprising;

a first bridge circuit, wherein the first bridge circuit is coupled to an AC voltage source to output a first voltage, and the first bridge circuit comprises a first positive input terminal, a first negative input terminal, a first positive output terminal and a first negative output terminal;

a second bridge circuit, wherein the second bridge circuit is coupled to the AC voltage source to output a second voltage, and the second bridge circuit comprises a second positive input terminal, a second negative input terminal, a second positive output terminal and a second negative output terminal, wherein the second negative output terminal and the first negative output terminal are coupled to the same ground potential;

a first protection device coupled between the second positive input terminal and the AC voltage source; and

a second protection device coupled between the second negative input terminal and the AC voltage source;

a light emitting module receiving the first voltage and enabled by the first voltage; and

a bluetooth module receiving the second voltage and enabled by the second voltage.

10. The lamp of claim 9, wherein the light emitting module further comprises a control module configured for receiving a control signal from the bluetooth module and controlling a plurality of light emitting devices in the lamp according to the control signal.

11. The lamp of claim 9, wherein the first protection device comprises a first capacitor and a first diode, and the second protection device comprises a second capacitor and a second diode.

12. The lamp of claim 11, wherein a power of the second bridge circuit is limited by capacitances of the first capacitor and the second capacitor.

13. The lamp of claim 11, wherein the first protection device and the second protection device form a non-polarized protection device.

14. The lamp of claim 13, wherein the non-polarized protection device comprises:

a first capacitor comprising a first anode and a first cathode, wherein the first anode is coupled to the AC voltage source;

a second capacitor comprising a second anode and a second cathode, wherein the second cathode is coupled to the first cathode, and the second anode is coupled to the first positive input terminal;

a first diode comprising a third anode and a third cathode, wherein the third anode is coupled to the first cathode, and the third cathode is coupled to the first anode; and

a second diode comprising a fourth anode and a fourth cathode, wherein the fourth anode is coupled to the second cathode, and the fourth cathode is coupled to the second anode.

15. The lamp of claim 9, wherein the first protection device and the second protection device are used for avoiding that an input current inputted from the first positive input terminal or the first negative input terminal of the first bridge circuit is fed back to the second positive input terminal or the second negative input terminal of the second bridge circuit.