Driving apparatus, backlight module, and driving method

• US 20090109163A1
• Filed: 12/20/2007
• Published: 04/30/2009
• Est. Priority Date: 10/26/2007
• Status: Abandoned Application

• Current Assignee: Quanta Computer
• Original Assignee: Quanta Computer
• Inventors: Yen, Wei-Ting
• Application Number:
  US12/003,187
• Publication Number:
  US 20090109163A1
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2330/04 Display protection
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

The invention discloses a driving apparatus for driving a back light module, and the driving apparatus comprises a driving unit and a deviation detecting unit. The driving unit is used for driving a plurality of lighting units to emit light. The deviation detecting unit is used for calculating for a current deviation of each of the lighting emitting units. Wherein, when the deviation overtakes a first threshold, the deviation detecting unit controls the driving unit to stop driving the lighting emitting units to light.

Claims

1. A driving apparatus, for driving a backlight module of a LCD, the driving apparatus comprising:

a driving unit for driving a plurality of light emitting units of the backlight module lighting; and

a deviation detecting unit for calculating a current deviation of each of the light emitting units;

wherein when the current deviation overtakes a first threshold, the deviation detecting unit controls the driving unit to stop driving the light emitting units lighting.

2. The driving apparatus of claim 1, wherein the deviation detecting unit further comprises:

a subtracter for measuring a current difference between each of the light emitting units respectively;

a comparator for calculating the current deviation of each of the light emitting units respectively according to the current difference and the current of each of the light emitting units; and

a sender for sending a first controlling signal to control the driving unit to stop driving the light emitting units lighting when the current deviation overtaking the first threshold.

3. The driving apparatus of claim 1, further comprising:

a protecting unit for sending a second controlling signal to control the driving unit to stop driving the light emitting units lighting when the voltage of any of the light emitting units in open circuit overtakes a second threshold.

4. The driving apparatus of claim 3, wherein deviation detecting unit further comprises:

a subtracter for measuring a current difference between each of the light emitting units respectively;

a comparator for calculating the current deviation of each of the light emitting units respectively according to the current difference and the current of each of the light emitting units; and

a sender for sending a first controlling signal to the protecting unit when the current deviation overtaking the first threshold, so that the protecting unit further sending the second controlling signal to control the driving unit to stop driving the light emitting units lighting.

5. The driving apparatus of claim 1, wherein the driving unit comprises at least one structure selected from a group consisting of a current-fed parallel resonance circuit, a half-bridge series resonance inverter, a full-bridge phase shift inverter, and a push-pull inverter.

6. The driving apparatus of claim 1, wherein the LCD is a thin-film transistor LCD (TFT-LCD).

7. The driving apparatus of claim 1, wherein the light emitting unit is a Cold Cathode Fluorescent Lamp (CCFL).

8. A backlight module, used in a LCD, the backlight module comprising:

a plurality of light emitting units; and

a driving apparatus for driving the light emitting units lighting and calculating a current deviation of each of the light emitting units;

wherein when the current deviation overtakes a first threshold, the driving apparatus stops driving the light emitting units lighting.

9. The backlight module of claim 8, wherein the driving apparatus further comprising:

a driving unit for driving the light emitting units lighting; and

a deviation detecting unit for calculating a current deviation of each of the light emitting units.

10. The backlight module of claim 9, wherein the driving apparatus further comprising:

a protecting unit for sending a second controlling signal to control the driving unit to stop driving the light emitting units lighting when the voltage of any of the light emitting units in open circuit overtakes a second threshold.

11. The backlight module of claim 9, wherein the driving unit comprises at least one structure selected from a group consisting of a current-fed parallel resonance circuit, a half-bridge series resonance inverter, a full-bridge phase shift inverter, and a push-pull inverter.

12. The backlight module of claim 8, wherein the LCD is a thin-film transistor LCD (TFT-LCD).

13. The backlight module of claim 8, wherein the light emitting unit is a Cold Cathode Fluorescent Lamp (CCFL).

14. A driving method for driving a backlight module of a LCD, the driving method comprising the following steps:

(a) driving a plurality of light emitting units of the backlight module lighting;

(b) calculating a current deviation of each of the light emitting units; and

(c) stopping driving the light emitting units lighting when the current deviation overtaking a first threshold.

15. The driving method of claim 14, wherein the step (b) further comprises the following steps:

(b1) measuring a current difference between each of the light emitting units; and

(b2) calculating the current deviation of each of the light emitting units respectively according to the current difference and the current of each of the light emitting units.

16. The driving method of claim 14, further comprising the following step:

(d) stopping driving the light emitting units lighting when the voltage of any of the light emitting units in open circuit overtaking a second threshold.

17. The driving method of claim 14, wherein the LCD is a thin-film transistor LCD (TFT-LCD).

18. The driving method of claim 14, wherein the light emitting unit is a Cold Cathode Fluorescent Lamp (CCFL).