CN101308623B - Liquid crystal display, back light device and driving method thereof - Google Patents
Liquid crystal display, back light device and driving method thereof Download PDFInfo
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- CN101308623B CN101308623B CN2007101041371A CN200710104137A CN101308623B CN 101308623 B CN101308623 B CN 101308623B CN 2007101041371 A CN2007101041371 A CN 2007101041371A CN 200710104137 A CN200710104137 A CN 200710104137A CN 101308623 B CN101308623 B CN 101308623B
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Abstract
Disclosed is a backlighting device, comprising a light source module which is provided with a plurality of luminous sources connected in series, and an electrical source which generates drive signals according to synchronous control signals generated based on the working state of the plurality of luminous sources to drive the light source module to radiate. The backlighting device is characterized in that a switch with the make-and-break determined according to the synchronous control signals, is arranged between the light source module and the electrical source module, or between the last luminous source of the light source module and the reference potential. In addition, the backlighting device is provided with a second switch which decides whether to couple the special functional terminal of the electric source to the reference potential or not according to the synchronous control signals. The drive signals are output under the condition that the special functional terminal of the electric source is coupled to the reference potential, and the drive signals are forbidden under the condition of not turning off the electric source when the special functional terminal of the electric source is in a floating connection state.
Description
Technical field
The present invention relates to a kind of Driving technique of light emitting source, and be particularly related to a kind of Driving technique that is used for the light emitting source of back lighting device.
Background technology
Fig. 1 is depicted as a kind of internal circuit calcspar of existing back lighting device.Please refer to Fig. 1, in existing back lighting device 100, comprised light emitting source module 110, it has a plurality of similarly is the light emitting source 112 of light emitting diode.These light emitting sources 112 are one another in series, and last light emitting source is then by resistance 114 ground connection.
In addition, can also dispose electric power driving module 130 in the existing back lighting device 100, it comes driven for emitting lights source module 110 according to the feedback voltage of light emitting source module 110 and produce drive current I1.And between electric power driving module 130 and light emitting source module 110, also disposing switch 140, it determines whether drive current I1 conducting to light emitting source module 110 according to control signal Vp, so that light emitting source module 110 is driven is luminous.
Fig. 2 illustrates the drive current of light emitting source module of Fig. 1 to the curve map of time.Please merge and see figures.1.and.2, when switch 140 cut out (Turn off), drive current I1 can not be switched on to light emitting source module 110, so that light emitting source module 110 is under an embargo.At this moment, light emitting source module 110 can not produce working current, and power module 130 can not detect any feedback signal yet, causes power module 130 erroneous judgement to think that the drive current I1 that is exported is not enough to driven for emitting lights source module 110, and the output driving current I1 that continues.
Owing in power module 130, can dispose for example energy-storage travelling wave tube such as electric capacity or inductance usually.Therefore, when switch 140 ended, still in action, drive current I1's electric power driving module 130 that electric power driving module 130 is exported can charge to these energy-storage travelling wave tubes at this moment.And when switch 140 conductings, because energy-storage travelling wave tube has stored electric energy, so its electric energy of meeting abrupt release, make big or small moment of drive current toward rise (part that is indicated as dotted line among Fig. 2 201), and the colour temperature that causes light emitting source module 110 produces error, and also can cause the waste of power.
Summary of the invention
Therefore, the invention provides a kind of back lighting device, it has preferable efficient and degree of stability.
In addition, the invention provides a kind of driving method of back lighting device, the waste that can make back lighting device have stable and accurate colour temperature and reduce power.
Back lighting device provided by the present invention, comprise the light emitting source module, it has a plurality of light emitting sources, and has power module, the synchronous control signal that can produce according to the duty according to described a plurality of light emitting sources produces drive signal, with the driven for emitting lights source module.Specifically, the present invention between light emitting source module and power module, or in the light emitting source module configuration first switch between last light emitting source and the reference potential, it determines whether conducting according to synchronous control signal.In addition, the present invention also has second switch, whether it determines according to synchronous control signal a specific function end of power module is coupled to reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid drive signal.
From another viewpoint, the invention provides a kind of driving method of back lighting device, it comprises that the duty according to described a plurality of light emitting sources produces synchronous control signal, and reference potential is provided.In addition, the present invention produces drive signal so that light emitting source according to the current potential of drive signal and this reference potential the two potential difference (PD) and be driven luminous.Specifically, whether meeting of the present invention determine according to synchronous control signal this drive signal conducting to these light emitting sources, and decision whether with the reference potential conducting to these light emitting sources the two at least one of them, to drive these light emitting sources.Except that this, whether the present invention also can determine according to this synchronous control signal the specific function end of the power module of back lighting device is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
From another viewpoint, the invention provides a kind of back lighting device, comprising: the light emitting source module has the light emitting source of a plurality of series connection; Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, and is luminous in order to drive this light emitting source module; First switch is configured in this light emitting source module between last light emitting source and reference potential, in order to determine whether conducting according to this synchronous control signal; And second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
From another viewpoint, the invention provides a kind of driving method of back lighting device, wherein this back lighting device has a plurality of light emitting sources, and this driving method comprises the following steps: to produce synchronous control signal according to the duty of described a plurality of light emitting sources; Reference potential is provided; Produce drive signal so that described a plurality of light emitting source according to the current potential of this drive signal and this reference potential the two potential difference (PD) and be driven luminous; Whether determine according to synchronous control signal described a plurality of light emitting source conductings to this reference potential; And whether determine according to this synchronous control signal the specific function end of the power module of back lighting device is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
From another viewpoint, the invention provides a kind of LCD, have back lighting device, and this back lighting device comprises: the light emitting source module has a plurality of light emitting sources; Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, in order to drive this light emitting source module; First switch is configured between this light emitting source module and this power module, in order to determine whether conducting according to this synchronous control signal; And second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
From another viewpoint, the invention provides a kind of LCD, have back lighting device, and this back lighting device comprises: the light emitting source module has the light emitting source of a plurality of series connection; Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, in order to drive this light emitting source module; First switch is configured in this light emitting source module between last light emitting source and reference potential, in order to determine whether conducting according to this synchronous control signal; And second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
Because the present invention can be with the drive signal conducting to the light emitting source module, or with the reference potential conducting to the light emitting source module, and under the situation of powered-down not, forbid drive signal synchronously.Therefore, the present invention can have more stable colour temperature, and has lower power dissipation.
For above-mentioned and other purposes, feature and advantage of the present invention can be become apparent, preferred embodiment cited below particularly, and conjunction with figs. are described in detail below.
Description of drawings
Fig. 1 is depicted as a kind of internal circuit calcspar of existing backlight module;
Fig. 2 illustrates the working current of light emitting source module of Fig. 1 to the curve map of time;
Fig. 3 illustrates the circuit block diagram according to a kind of back lighting device of first embodiment of the invention;
Fig. 4 illustrates the flow chart of steps according to the driving method of a kind of back lighting device of first embodiment of the invention;
Fig. 5 is depicted as the circuit diagram according to a kind of power module of preferred embodiment of the present invention;
Fig. 6 is depicted as the circuit diagram according to a kind of power module of another embodiment of the present invention;
Fig. 7 is depicted as the circuit diagram according to a kind of back lighting device of second embodiment of the invention;
Fig. 8 illustrates the flow chart of steps according to the driving method of a kind of back lighting device of second embodiment of the invention.
Embodiment
Hereinafter, will specifically describe embodiment of the present invention in conjunction with the accompanying drawings.Need to prove that the solution of the present invention can be carried out multi-form change; Scope of the present invention has more than and is limited to the described part of embodiment.Embodiment herein is just in order to make those skilled in the art can more fully understand the present invention.The size of accompanying drawing has just for the sake of clarity been done corresponding amplification.Wherein, similar components is all represented with similar numeral in the full text.In addition, the transistor version in the accompanying drawing only is explanation usefulness, and those skilled in the art can be according to the multi-form transistor of situation displacement of reality.
Fig. 3 illustrates the circuit block diagram according to a kind of back lighting device of first embodiment of the invention.Please refer to Fig. 3, can be used in the LCD at back lighting device 300 provided by the present invention, comprised light emitting source module 310, it has a plurality of light emitting sources 312.In the present embodiment, light emitting source 312 can be a light emitting diode, and the cathode terminal of each light emitting diode all is coupled to the anode tap of next light emitting diode, and the cathode terminal of last light emitting diode, then by resistance 314 ground connection.Right those skilled in the art as can be known, the light emitting source 312 in the present embodiment can adopt series, parallel or the shared connected mode of connection in series-parallel.
In addition, also comprised electric power driving module 320 in back lighting device 300, it is luminous with driven for emitting lights source module 310 that its feedback voltage V b according to light emitting source module 310 produces drive signal Id.In an embodiment of the present invention, drive signal Id can be a current signal.More specifically, electric power driving module 320 can have specific function end S.When this specific function end S was enabled, then power module 320 will output drive signal Id.And in the present embodiment, the specific function end S of power module 320 is coupled to reference potential Vref by switch 332, for example is ground (ground).In addition, 332 on switch is to determine whether conducting according to synchronous control signal Vc.
In the present embodiment, switch 332 can utilize nmos pass transistor to realize.Wherein, first source of switch 332/drain electrode end is coupled to reference potential Vref, and second source/drain electrode end couples the specific function end S of power module 320.In addition, the gate terminal of switch 332 then receives synchronous control signal Vc.
In addition, between power module 320 and light emitting source module 310, can also dispose another switch 334, it can determine whether drive signal Id conducting to light emitting source module 310 according to synchronous control signal Vc.In the present embodiment, switch 334 also can utilize nmos pass transistor to realize.Wherein, first source of switch 334/drain electrode end receives the drive signal Id that power module 320 is exported, and its second source/drain electrode end then is coupled to the anode tap of a light emitting diode in the light emitting source module 310.In addition, the gate terminal of switch 334 also is coupled to its first source/drain electrode end by resistance 341.
In back lighting device 300, between synchronous control signal Vc and switch 334, go back configurable switch 336.Similarly, switch 336 can utilize nmos pass transistor to realize.Wherein, first source of switch 336/drain electrode end ground connection, its gate terminal receives synchronous control signal Vc, and its second source/drain electrode end then can be coupled to the gate terminal of switch 334 by resistance 338.
Fig. 4 illustrates the flow chart of steps according to the driving method of a kind of back lighting device of first embodiment of the invention.Please merge with reference to Fig. 3 and Fig. 4, at first, in step S401, control module 330 produces synchronous control signal Vc in order to gauge tap 332 and switch 336.Moreover, in step S403, providing reference potential Vref, earthing potential for example is at the first source/drain electrode end of switch 332.Then, as described in step S405, power module 320 produces drive signal Id.In addition, whether switch 334 can determine according to synchronous control signal Vc drive signal Id conducting to light emitting source module 310, just as described in the step S407, and switch 332 also can be as described in the step S409, whether determines the specific function end S ground connection with power module 320 according to synchronous control signal Vc.
When needs driven for emitting lights source module 310 was luminous, then can to make synchronous control signal Vc be high potential state to control module 330.At this moment, switch 332 and 336 all can conducting.Because switch 332 conductings, so the specific function end S of power module 320 meeting ground connection make that power module 320 can output drive signal Id.In addition, because switch 336 is the state of conducting, so the gate terminal of switch 334 can pass through resistance 338 ground connection, causes switch 334 conductings, and makes drive signal Id conducting to light emitting source module 310, and is luminous with driven for emitting lights source 312.
When synchronous control signal Vc was low-potential state, then switch 332 and switch 336 all ended.At this moment, specific function end S is a floating, causes power module 320 to forbid drive signal Id under the situation of powered-down not.In addition, switch 334 also can end because switch 336 ends, thereby causes light emitting source module 310 to be under an embargo.
Because the present invention can forbid drive signal Id and light emitting source module 310 synchronously, so the present invention overcharges and causes drive signal Id that the phenomenon that moment rises is arranged energy-storage travelling wave tube with regard to not having.Also because so, the present invention has higher stable degree and lower power attenuation.
In addition, because the present invention forbids drive signal Id under the situation of powered-down not.Therefore, drive signal Id has short switching time when transition.
Fig. 5 is depicted as the circuit diagram according to a kind of power module of preferred embodiment of the present invention.Please refer to Fig. 5, in power module 3201, comprised voltage source 500, power supply control chip 504 and reduction voltage loop 510.Wherein, energy supply control module 504 has above-mentioned specific function end S, and it is by switch 332 to reference potential Vref, and the output K1 of energy supply control module 504 is coupled to reduction voltage loop 510.By this, when switch 332 conductings, power supply control chip 504 will make reduction voltage loop 510 drive signal Id.
And in reduction voltage loop 510, having comprised PMOS transistor 512, its first source/drain electrode end is coupled to the cathode terminal of diode 514, and by diode 514 ground connection, its gate terminal then receives the output K1 of power supply control chip.In addition, second source of PMOS transistor 512/drain electrode end is coupled to voltage source 500.In addition, also have inductance 516 in power module 3201, wherein an end is coupled to the second source/drain electrode end of PMOS transistor 512, and the other end is then by electric capacity 518 ground connection.
Fig. 6 is depicted as the circuit diagram according to a kind of power module of another embodiment of the present invention.Please refer to Fig. 6, in power module 3202, equally also comprise voltage source 500 and power supply control chip 504.In addition, power module 3202 has also comprised the loop 610 of boosting.Wherein, the power supply control chip of power supply control chip 504 and Fig. 5 504 is the same to have specific function end S, and its output K2 is coupled to the loop 610 of boosting.
In the loop 610 of boosting, comprised nmos pass transistor 612, its first source/drain electrode end ground connection, its gate terminal receives the output K2 of energy supply control module 504, and its second source/drain electrode end is coupled to voltage source 500 by inductance 614.In addition, second source of nmos pass transistor 612/drain electrode end is coupled to the anode tap of diode 616, and the cathode terminal of diode 616 is then by electric capacity 618 ground connection.As from the foregoing, power supply control chip 504 can be controlled the loop 610 output drive signal Id that boost according to synchronous control signal Vc.
Fig. 7 is depicted as the circuit diagram according to a kind of back lighting device of second embodiment of the invention.Please refer to Fig. 7, in back lighting device 700 provided by the present invention, equally also comprise light emitting source module 710, it has the light emitting source 712 of a plurality of series connection, for example the light emitting diode for connecting.Wherein, the cathode terminal of each light emitting diode all is coupled to the anode tap of next light emitting diode, and the anode tap of first light emitting diode then receives drive signal Id.
Specifically, the cathode terminal of last light emitting diode in light emitting source module 710 is coupled to resistance 716 by switch 714, and by resistance 716 ground connection.
In the present embodiment, switch 714 can utilize nmos pass transistor to realize.Wherein, first source of switch 714/drain electrode end is by resistance 716 ground connection, and its second source/drain electrode end then couples the cathode terminal of last light emitting diode in the light emitting source module 710.In addition, the gate terminal of switch 714 then is coupled to the gate terminal of switch 732 by resistance 738, to receive synchronous control signal Vc.
Please continue with reference to Fig. 7, equally also comprise power module 720 in back lighting device 700, it can give light emitting source module 710 and produce drive signal Id according to the feedback voltage V b of light emitting source module 710.And power module 720 also has specific function end S, and is coupled to reference potential Vref, for example ground connection by switch 732.When switch 732 during with specific function end S conducting ground connection, power module 720 will produce drive signal Id.And the circuit structure of power module 720 can be with reference to the narration of Fig. 5 and Fig. 6.
Fig. 8 illustrates the flow chart of steps according to the driving method of a kind of back lighting device of second embodiment of the invention.Please merge with reference to Fig. 7 and Fig. 8, in back lighting device 700, dispose control module 730 equally, it is used for as step S801 described, produces synchronous control signal Vc.In addition, back lighting device 700 also as described in the step S803, provides for example reference potential of ground connection.
In addition, power module 720 is as described in the step S805, produces drive signal Id.Whether when power module 720 produced drive signal Id, switch 714 will be as described in the step S807, determine according to synchronous control signal Vc with light emitting source 712 conducting ground connection.
In detail, when control module 730 was exported the synchronous control signal Vc of high level, switch 732 and 714 all can conducting.At this moment, the specific function end S of power module 720 meeting ground connection makes power module 720 produce drive signal Id and gives light source module 710.In addition, because therefore switch 714 conductings make to be driven light source module 710 ground connection and can respond drive signal Id luminous.
When synchronous control signal Vc was low level, then switch 732 and 714 can end simultaneously.At this moment, the specific function end S of power module 720 can be by suspension joint, causes power module 720 just can forbid drive signal Id under the situation of powered-down not, just the content of step S809.In addition, because switch 714 ends, so light emitting source 712 just can not be switched on ground connection, and because drive signal Id is under an embargo, and causes light emitting source module 710 to be under an embargo.
In sum, the present invention can be in the front and back end of light emitting source, and sets up switch on the specific function end of power module, and determines whether conducting according to synchronous control signal.Therefore back lighting device provided by the present invention has higher stable degree and lower power attenuation.
In addition, though above front end or the backend arrangement switch that only is chosen in light emitting source, those skilled in the art also can dispose switch in the front and back end of light emitting source simultaneously, and this does not influence main spirit of the present invention.
Though the present invention discloses as above with preferred embodiment; right its is not in order to limit the present invention; any those skilled in the art; without departing from the spirit and scope of the present invention; when can doing a little change and retouching, so protection scope of the present invention is as the criterion when looking the accompanying Claim person of defining.
Claims (13)
1. back lighting device comprises:
The light emitting source module has a plurality of light emitting sources;
Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, in order to drive this light emitting source module;
First switch is configured between this light emitting source module and this power module, determines the whether conducting of this first switch according to this synchronous control signal; And
Second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
2. back lighting device as claimed in claim 1, wherein this first switch is a nmos pass transistor, its first source/drain electrode end receives this drive signal, its second source/drain electrode end couples this light emitting source module, and its gate terminal is coupled to this reference potential by the 3rd switch, and is coupled to the first source/drain electrode end of this first switch by resistance.
3. back lighting device as claimed in claim 2, wherein the 3rd switch is a nmos pass transistor, its first source/drain electrode end ground connection, its gate terminal receives this synchronous control signal, and its second source/drain electrode end then is coupled to the gate terminal of this first switch.
4. the driving method of a back lighting device, wherein this back lighting device has a plurality of light emitting sources, and this driving method comprises the following steps:
Duty according to described a plurality of light emitting sources produces synchronous control signal;
Reference potential is provided;
Produce drive signal so that described a plurality of light emitting source according to the current potential of this drive signal and this reference potential the two potential difference (PD) and be driven;
Whether determine according to synchronous control signal this drive signal conducting to described a plurality of light emitting sources; And
Whether determine according to this synchronous control signal the specific function end of the power module of back lighting device is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
5. back lighting device comprises:
The light emitting source module has the light emitting source of a plurality of series connection;
Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, and is luminous in order to drive this light emitting source module;
First switch is configured in this light emitting source module between last light emitting source and reference potential, in order to determine whether conducting according to this synchronous control signal; And
Second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
6. back lighting device as claimed in claim 5, wherein this first switch is a nmos pass transistor, its the first source/drain electrode end and second source/drain electrode end couples last light emitting source and reference potential respectively, and the gate terminal of this nmos pass transistor then is coupled to this reference potential by this second switch.
7. the driving method of a back lighting device, wherein this back lighting device has a plurality of light emitting sources, and this driving method comprises the following steps:
Produce synchronous control signal according to the duty of described a plurality of light emitting sources;
Reference potential is provided;
Produce drive signal so that described a plurality of light emitting source according to the current potential of this drive signal and this reference potential the two potential difference (PD) and be driven luminous;
Whether determine according to synchronous control signal described a plurality of light emitting source conductings to this reference potential; And
Whether determine according to this synchronous control signal the specific function end of the power module of back lighting device is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
8. LCD have back lighting device, and this back lighting device comprises:
The light emitting source module has a plurality of light emitting sources;
Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, in order to drive this light emitting source module;
First switch is configured between this light emitting source module and this power module, in order to determine whether conducting according to this synchronous control signal; And
Second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
9. LCD as claimed in claim 8, wherein this first switch is a nmos pass transistor, its first source/drain electrode end receives this drive signal, its second source/drain electrode end couples this light emitting source module, and its gate terminal is coupled to this reference potential by the 3rd switch, and is coupled to the first source/drain electrode end of this first switch by resistance.
10. LCD as claimed in claim 9, wherein the 3rd switch is a nmos pass transistor, its first source/drain electrode end ground connection, its gate terminal receives this synchronous control signal, and its second source/drain electrode end then is coupled to the gate terminal of this first switch.
11. LCD as claimed in claim 8, wherein said a plurality of light emitting source is a light emitting diode, the cathode terminal of last light emitting diode is by resistance eutral grounding, and the cathode terminal of each other light emitting diode all is coupled to the anode tap of next light emitting diode.
12. a LCD have back lighting device, and this back lighting device comprises:
The light emitting source module has the light emitting source of a plurality of series connection;
Power module, the synchronous control signal that produces according to the duty according to described a plurality of light emitting sources produces drive signal, in order to drive this light emitting source module;
First switch is configured in this light emitting source module between last light emitting source and reference potential, in order to determine whether conducting according to this synchronous control signal; And
Second switch, whether determine according to this synchronous control signal the specific function end of this power module is coupled to this reference potential, be coupled to this drive signal of output under the situation of this reference potential at the specific function end of this power module, and when the specific function end of this power module is floating in order under the situation of powered-down not, to forbid this drive signal.
13. LCD as claimed in claim 12, wherein this first switch is a nmos pass transistor, its the first source/drain electrode end and second source/drain electrode end couples last light emitting source and reference potential respectively, and the gate terminal of this nmos pass transistor then is coupled to this reference potential by this second switch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101041371A CN101308623B (en) | 2007-05-16 | 2007-05-16 | Liquid crystal display, back light device and driving method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007101041371A CN101308623B (en) | 2007-05-16 | 2007-05-16 | Liquid crystal display, back light device and driving method thereof |
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| Publication Number | Publication Date |
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| CN101308623A CN101308623A (en) | 2008-11-19 |
| CN101308623B true CN101308623B (en) | 2011-11-02 |
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| TWI452925B (en) * | 2011-06-30 | 2014-09-11 | Hannstar Display Corp | Control circuit and dimming method of light emitting diode |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5576601A (en) * | 1991-10-11 | 1996-11-19 | Norand Corporation | Drive circuit for electroluminescent panels and the like |
| CN1693966A (en) * | 2005-06-15 | 2005-11-09 | 友达光电股份有限公司 | Backlight module structure |
| CN1924672A (en) * | 2005-08-31 | 2007-03-07 | 三星电子株式会社 | Backlight unit, display device having the same and method of controlling a light source |
| CN1928663A (en) * | 2005-09-05 | 2007-03-14 | 三星电子株式会社 | Liquid crystal display and method for lighting the same |
-
2007
- 2007-05-16 CN CN2007101041371A patent/CN101308623B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5576601A (en) * | 1991-10-11 | 1996-11-19 | Norand Corporation | Drive circuit for electroluminescent panels and the like |
| CN1693966A (en) * | 2005-06-15 | 2005-11-09 | 友达光电股份有限公司 | Backlight module structure |
| CN1924672A (en) * | 2005-08-31 | 2007-03-07 | 三星电子株式会社 | Backlight unit, display device having the same and method of controlling a light source |
| CN1928663A (en) * | 2005-09-05 | 2007-03-14 | 三星电子株式会社 | Liquid crystal display and method for lighting the same |
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| CN101308623A (en) | 2008-11-19 |
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