SYSTEM FOR DRIVING A PLURALITY OF LAMPS AND FAULT DETECTING CIRCUIT THEREOF

• US 20070115001A1
• Filed: 04/28/2006
• Published: 05/24/2007
• Est. Priority Date: 11/18/2005
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hon Hai Precision Industry Co., Ltd.
• Inventors: Ger, Chih-Chan, Kan, Chi-Wen, Chen, Chia-Kun
• Granted Patent: US 7,362,103 B2
• Time in Patent Office: Days
• US Class Current: 324/414
• CPC Class Codes: H05B 41/2855 against abnormal lamp operating conditions

Abstract

A system for driving a plurality of lamps includes an inverter circuit (20) and a fault detecting circuit (30). The inverter circuit includes a plurality of outputs divided into a first output part and a second output part. The fault detecting circuit is used for detecting whether one or more of the plurality of outputs of the inverter circuit is faulty, and includes a magnetic element circuit (300) and a signal detecting circuit (310). The magnetic element circuit is used for generating an induction signal according to flux changes of the magnetic element circuit when one of the plurality of outputs is faulty. The signal detecting circuit is used for generating a fault signal according to the induction signal.

Claims

1. A system for driving a plurality of lamps, comprising:

an inverter circuit comprising a plurality of outputs, wherein the plurality of outputs are divided into a first output part and a second output part; and

a fault detecting circuit for detecting whether one or more of the plurality of outputs of the inverter circuit is faulty, comprising;

a magnetic element circuit for generating an induction signal according to flux changes thereof when one or more of the plurality of outputs is faulty; and

a signal detecting circuit for generating a fault signal according to the induction signal.

2. The system of claim 1, wherein the magnetic element circuit comprises:

a first magnetic element winding connected to the first output part;

a second magnetic element winding connected to the second output part; and

a third magnetic element winding for generating the induction signal when one or more of the plurality of outputs is faulty.

3. The system of claim 2, wherein a winding ratio between the first magnetic element winding and the second magnetic element winding is reverse to a ratio between a number of outputs of the first output part and a number of outputs of the second output part.

4. The system of claim 2, wherein the induction signal is a current signal.

5. The system of claim 2, wherein the signal detecting circuit comprises:

a rectifier circuit comprising four nodes that are connected one by one, wherein two opposite nodes are respectively connected to two ends of the third magnetic element winding; and

a resistor connected between the other two opposite nodes of the rectifier circuit.

6. The system of claim 5, wherein the rectifier circuit comprising four diodes connected one by one, wherein each diode is connected to two nodes.

7. The system of claim 5, wherein the fault signal is a voltage signal.

8. The system of claim 5, wherein the resistor has one end grounded.

9. A fault detecting circuit, for use in an inverter circuit comprising a plurality of outputs, and for detecting whether one or more of the plurality of outputs is faulty, comprising:

a magnetic element circuit; and

a signal detecting circuit;

wherein the plurality of outputs of the inverter circuit are divided into a first output part and a second output part;

wherein the magnetic element circuit is used for generating an induction signal according to flux changes of the magnetic element circuit when one of the plurality of outputs is faulty; and

wherein the signal detecting circuit is used for generating a fault signal according to the induction signal.

10. The fault detecting circuit of claim 9, wherein the magnetic element circuit comprises:

a first magnetic element winding for connecting to the first output part of the inverter circuit;

a second magnetic element winding for connecting to the second output part of the inverter circuit; and

a third magnetic element winding for generating the induction signal when one of the plurality of the outputs is faulty.

11. The fault detecting circuit of claim 9, wherein a proportion between the first magnetic element winding and the second magnetic element winding is reverse to a proportion between a number of the outputs of the first output part and a number of the outputs of the second output part.

12. The fault detecting circuit of claim 9, wherein the induction signal is a current signal.

13. The fault detecting circuit of claim 9, wherein the signal detecting circuit comprises:

a rectifier circuit comprising four nodes, wherein two opposite nodes are respectively connected to two ends of the third magnetic element winding; and

a resistor connected between the other two opposite nodes of the rectifier circuit.

14. The fault detecting circuit of claim 13, wherein the fault signal is a voltage signal.

15. The fault detecting circuit of claim 13, wherein the resistor has one end grounded.

16. The fault detecting circuit of claim 13, where the rectifier circuit comprising four diodes connected one by one, wherein every diode is connected to two nodes.