CN205754936U - Backlight drive circuit and television set - Google Patents
Backlight drive circuit and television set Download PDFInfo
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- CN205754936U CN205754936U CN201620081255.XU CN201620081255U CN205754936U CN 205754936 U CN205754936 U CN 205754936U CN 201620081255 U CN201620081255 U CN 201620081255U CN 205754936 U CN205754936 U CN 205754936U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
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Abstract
The open a kind of backlight drive circuit of this utility model and television set, wherein backlight drive circuit, including the first lamp bar and to the transformer circuit of the first lamp bar offer working power, transformer circuit includes transformator, the first capacitor filter and light adjusting circuit；Transformator and the first capacitive filter are connected, and light adjusting circuit has a power input, drive output and for receiving the signal input part of dim signal；The outfan of the first capacitor filter is connected with the power input of light adjusting circuit, and the drive output of light adjusting circuit is connected with the first lamp bar；Light adjusting circuit includes switching tube and switch controlled circuit；The input of switching tube is the power input of light adjusting circuit, the outfan of switching tube is the drive output of light adjusting circuit, the controlled end of switching tube is connected with the control end of switch controlled circuit, and the input of switch controlled circuit is the signal input part of light adjusting circuit.Technical solutions of the utility model have the advantages that dimming scope is wide.
Description
Technical field
This utility model relates to technical field of television sets, particularly to a kind of backlight drive circuit and television set.
Background technology
Traditional backlight drive circuit includes lamp bar and transformer circuit as shown in Figure 1, and primary source voltage is powered to lamp bar after the diode rectification in transformer circuit and output capacitance filter.
Although this backlight drive circuit can realize the driving to lamp bar, but owing to this backlight drive circuit can only realize the brightness adjustment control to lamp bar by controlling the make and break period of drive circuit power supply.When controlling the power remove of drive circuit, because two filter capacitors of transformer secondary output outfan have energy storage effect, make lamp bar also have the electric current being gradually reduced to power, so, the dim signal of drive circuit it would appear that slope, and makes the dimming scope of backlight drive circuit reduce when trailing edge.
Utility model content
Main purpose of the present utility model is to provide a kind of backlight drive circuit, it is intended to widen the dimming scope of this backlight drive circuit.
For achieving the above object, the backlight drive circuit that the utility model proposes includes the first lamp bar and provides the transformer circuit of working power to described first lamp bar, wherein, described transformer circuit includes transformator, the first rectification circuit, the first capacitor filter and light adjusting circuit；Described light adjusting circuit has a power input, drive output and for receiving the signal input part of dim signal；The input of described first rectification circuit is connected with the first secondary output end of described transformator, and the outfan of described first rectification circuit is connected with the input of described first capacitor filter；The outfan of described first capacitor filter is connected with the power input of described light adjusting circuit, and the drive output of described light adjusting circuit is connected with described first lamp bar.
Preferably, described light adjusting circuit includes switching tube and switch controlled circuit；The input of described switching tube is the power input of described light adjusting circuit, the outfan of described switching tube is the drive output of described light adjusting circuit, the controlled end of described switching tube is connected with the control end of described switch controlled circuit, the signal input part that input is described light adjusting circuit of described switch controlled circuit.
Preferably, described switching tube is the first audion, the input of the most described switching tube of current collection of described first audion, the outfan of the most described switching tube of transmitting of described first audion, the controlled end that base stage is described switching tube of described first audion.
Preferably, described switch controlled circuit includes the first resistance, the second resistance, the second audion, the 3rd audion and accessory power supply；First end of described first resistance is the control end of described switch controlled circuit, second end of described first resistance is connected with the colelctor electrode of described second audion, the emitter stage of described second audion is connected with the positive output end of described accessory power supply, the negative output terminal ground connection of described accessory power supply；The base stage of described second audion is connected with the first end of described second resistance, second end of described second resistance is connected with the colelctor electrode of described 3rd audion, described 3rd transistor emitter ground connection, the signal input part that base stage is described switch controlled circuit of described 3rd audion.
Preferably, described first rectification circuit includes that the first diode and the second diode, described first capacitor filter include the first electric capacity；The anode of described first diode is connected with the negative electrode of described second diode, the link node of described first diode and described second diode is the input of described first rectification circuit, the negative electrode of described first diode is connected with the positive pole of described first electric capacity, and the anode of described second diode is connected with the negative pole of described first electric capacity；The positive pole of described first electric capacity also colelctor electrode with described first audion is connected, and the negative pole of described first electric capacity also negative drive end with described first lamp bar is connected, and the positive drive end of described first lamp bar is connected with the emitter stage of described first audion.
Preferably, described backlight drive circuit also includes the second lamp bar, and described transformer circuit also includes second subprime outfan, the second rectification circuit and the second capacitor filter；The input of described second rectification circuit is connected with described second subprime outfan, the outfan of described second rectification circuit is connected with the input of described second capacitor filter, the outfan of described second capacitor filter is connected with the power input of described light adjusting circuit, and the drive output of described light adjusting circuit is connected with described second lamp bar.
Preferably, described second rectification circuit includes that the 3rd diode and the 4th diode, described second capacitor filter include the second electric capacity；The anode of described 3rd diode is connected with the negative electrode of described 4th diode, described 3rd diode and the input that link node is described second rectification circuit of described 4th diode；The negative electrode of described 3rd diode is connected with the positive pole of described second electric capacity, and the anode of described 4th diode is connected with the negative pole of described second electric capacity；The positive pole of described second electric capacity also colelctor electrode with the first audion is connected, and the negative pole of described second electric capacity also negative drive end with the second lamp bar is connected, and the positive drive end of the second lamp bar and the emitter stage of the first audion are connected.
Preferably, described transformer circuit also includes that current-sharing electric capacity, the first end of described current-sharing electric capacity are connected with described second subprime outfan, and the second end of described current-sharing electric capacity is connected with the input of described second rectification circuit.
This utility model also proposes a kind of television set, and this television set includes above-mentioned backlight drive circuit；Wherein, described backlight drive circuit includes the first lamp bar and provides the transformer circuit of working power to described first lamp bar, and described transformer circuit includes the first secondary output end, the first rectification circuit, the first capacitor filter and light adjusting circuit；Described light adjusting circuit has a power input, drive output and for receiving the signal input part of dim signal；The input of described first rectification circuit is connected with described first secondary output end, and the outfan of described first rectification circuit is connected with the input of described first capacitor filter；The outfan of described first capacitor filter is connected with the power input of described light adjusting circuit, and the drive output of described light adjusting circuit is connected with described first lamp bar.
Technical solutions of the utility model are set up light adjusting circuit by employing and are controlled the break-make realization of the current loop that lamp bar is formed with the transformer circuit brightness adjustment control to lamp bar.Backlight drive terminal circuit owing to the utility model proposes is the control that the current path by getting through and block between the first lamp bar and transformer circuit realizes opening and shutting off the first lamp bar, it is achieved that the moment of described first lamp bar is on or off.Therefore, rising edge and the trailing edge of the backlight drive circuit dimming waveform that the utility model proposes are the most precipitous, have widened the dimming scope of backlight drive circuit.Relative to prior art, technical solutions of the utility model have the advantages that dimming scope is wide.
Accompanying drawing explanation
In order to be illustrated more clearly that this utility model embodiment or technical scheme of the prior art, the accompanying drawing used required in embodiment or description of the prior art will be briefly described below, apparently, accompanying drawing in describing below is only embodiments more of the present utility model, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to obtain other accompanying drawing according to the structure shown in these accompanying drawings.
Fig. 1 is the electrical block diagram of backlight drive circuit in prior art；
Fig. 2 is the high-level schematic functional block diagram of this utility model backlight drive circuit one embodiment；
Fig. 3 is the electrical block diagram of this utility model another embodiment of backlight drive circuit.
Drawing reference numeral illustrates:
| Label | Title | Label | Title |
| 30 | Transformer circuit | C1 | First output capacitance |
| 100 | First rectification circuit | C2 | Second output capacitance |
| 200 | Second rectification circuit | C3 | Current-sharing electric capacity |
| 300 | First capacitor filter | D1 | First diode |
| 400 | Second capacitor filter | D2 | Second diode |
| 500 | Light adjusting circuit | D3 | 3rd diode |
| 600 | Switching tube | D4 | 4th diode |
| 700 | Switch controlled circuit | T | Transformator |
| 800 | Transformator | Q1 | First audion |
| 10 | First lamp bar | Q2 | Second audion |
| 20 | Second lamp bar | Q3 | 3rd audion |
| R1 | First resistance | VAUX | Accessory power supply |
| R2 | Second resistance |
The realization of this utility model purpose, functional characteristics and advantage will in conjunction with the embodiments, are described further referring to the drawings.
Detailed description of the invention
Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the present utility model rather than whole embodiments.Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art are obtained under not making creative work premise, broadly fall into the scope of this utility model protection.
The description relating to " first ", " second " etc. in this utility model is only used for describing purpose, and it is not intended that indicate or imply its relative importance or the implicit quantity indicating indicated technical characteristic.Thus, define " first ", the feature of " second " can express or implicitly include at least one this feature.Additionally; technical scheme between each embodiment can be combined with each other; but must be based on those of ordinary skill in the art are capable of; when technical scheme combination occur conflicting maybe cannot realize time will be understood that the combination of this technical scheme does not exists, the most not this utility model require protection domain within.
The utility model proposes a kind of backlight drive circuit.
It is the high-level schematic functional block diagram of this utility model backlight drive circuit one embodiment with reference to Fig. 2 to 3, Fig. 2；Fig. 3 is the electrical block diagram of this utility model another embodiment of backlight drive circuit.
As in figure 2 it is shown, in this utility model embodiment, this backlight drive circuit includes the first lamp bar 10 and provides the transformer circuit 30 of working power to described first lamp bar 10；Wherein, described transformer circuit 30 includes transformator the 800, first rectification circuit the 100, first capacitor filter 300 and light adjusting circuit 500；Described light adjusting circuit 500 has a power input, drive output and for receiving the signal input part of dim signal；The input of described first rectification circuit 100 is connected with the first secondary output end of described transformator 800, and the outfan of described first rectification circuit 100 is connected with the input of described first capacitor filter 300；The outfan of described first capacitor filter 300 is connected with the power input of described light adjusting circuit 500, and the drive output of described light adjusting circuit 500 is connected with described first lamp bar 10.
When described backlight drive circuit is opened, described first rectification circuit 100 is delivered to described first capacitor filter 300 after the supply voltage of described first secondary output end output is carried out rectification process.Described supply voltage is filtered processing and exporting at its outfan by described first capacitor filter 300.
When to the signal input part input high level of described light adjusting circuit 500, the power input of described light adjusting circuit 500 connects with drive output, and described first lamp bar 10 obtains driving voltage, described first lamp bar 10 instant igniting.
When to the signal input part input low level of described light adjusting circuit 500, the power input of described light adjusting circuit 500 disconnects with drive output, and described first lamp bar 10 does not has driving voltage, described first lamp bar 10 moment to extinguish.
It should be noted that by the break-make duration controlling described light adjusting circuit 500, it is possible to achieve the regulation to the brightness of described first lamp bar 10.Because the switches switching frequency of described light adjusting circuit 500 is very fast, so, can't there is OFF state in eye-observation to described first lamp bar 10, and simply brightness difference can occur because of the change of the break-make duration of light adjusting circuit 500.
Technical solutions of the utility model are set up light adjusting circuit 500 by employing and are controlled the break-make realization of the current loop that the first lamp bar 10 is formed with transformer circuit 30 brightness adjustment control to the first lamp bar 10.Backlight drive terminal circuit owing to the utility model proposes is the control opened and shut off that the current path by getting through and block between the first lamp bar 10 and transformer circuit 30 realizes to the first lamp bar 10, it is achieved that the moment of described first lamp bar 10 is on or off.Therefore, rising edge and the trailing edge of the backlight drive circuit dimming waveform that the utility model proposes are the most precipitous, have widened the dimming scope of backlight drive circuit.Relative to prior art, technical solutions of the utility model have the advantages that dimming scope is wide.
Preferably, as it is shown on figure 3, described light adjusting circuit 500 includes switching tube 600 and switch controlled circuit 700；The input of described switching tube 600 is the power input of described light adjusting circuit 500, the outfan of described switching tube 600 is the drive output of described light adjusting circuit 500, the controlled end of described switching tube 600 is connected with the control end of described switch controlled circuit 700, and the input DIM of described switch controlled circuit 700 is the signal input part DIM of described light adjusting circuit 500.
When the magnitude of voltage of the dim signal that the input DIM of described switch controlled circuit 700 inputs is higher than the first voltage threshold, the output of described switch controlled circuit 700 controls the level signal that described switching tube 600 is opened, makes described switching tube 600 turn on；When the magnitude of voltage of the dim signal that the input DIM of described switch controlled circuit 700 inputs is less than described first voltage threshold, the output of described switch controlled circuit 700 controls the level signal that described switching tube 600 turns off, make described switching tube 600 turn off, thus achieve and realize the regulation to the first lamp bar 10 brightness by controlling the ON/OFF of switching tube 600.Wherein, owing to switch controlled circuit 700 receives after dim signal carries out switch process, the dim signal enabling to input unstable transfers stable high/low level signal to, control switching tube 600 again when turning on or turn off, just can improve the response speed of switching tube, and then improve the switch efficiency of switching tube 600.It should be noted that, when so can avoid because of input dim signal instability, i.e. high level redirects to low level or low level redirects to high level when there is slope, and makes switching tube occur half conducting or half off state during open/close, and then affects the stable operation of circuit.
In the present embodiment, above-mentioned switching tube 600 can be the first audion Q1, the input of the most described switching tube of current collection 600 of described first audion Q1, the outfan of the most described switching tube of transmitting 600 of described first audion Q1, the controlled end that base stage is described switching tube 600 of described first audion Q1.
Concrete, above-mentioned switch controlled circuit 700 includes the first resistance R1, the second resistance R2, the second audion Q2, the 3rd audion Q3 and accessory power supply VAUX；The control end that first end is described switch controlled circuit 700 of described first resistance R1, second end of described first resistance R1 is connected with the colelctor electrode of described second audion Q2, the emitter stage of described second audion Q2 is connected with the positive output end of described accessory power supply VAUX, the negative output terminal ground connection GND of described accessory power supply VAUX, and be connected with the colelctor electrode of described first audion Q1；The base stage of described second audion Q2 is connected with first end of described second resistance R2, second end of described second resistance R2 is connected with the colelctor electrode of described 3rd audion Q3, described 3rd audion Q3 grounded emitter GND, the input DIM that base stage is described switch controlled circuit 700 of described 3rd audion Q3.It should be noted that in the present embodiment, described first audion Q1 is NPN type triode, described second audion Q2 is PNP type triode, and described 3rd audion Q3 is NPN type triode.Wherein, the dim signal that the base stage of the 3rd audion Q3 receives is turned on when high level overturns by low level, the base stage making the second audion Q2 is connected to ground by the second resistance R2, now the base voltage of the second audion Q2 is relatively low relative to its emitting voltage, now, second audion Q2 turns on rapidly, the voltage signal making accessory power supply VAUX export quickly is transferred to the base stage of the first audion Q1, identical with the conducting principle of the second audion Q2, first audion Q1 turns on the most rapidly, thus realize improving the first audion Q1, namely the purpose of the switch efficiency of switching tube 600.
Above-mentioned first rectification circuit 100 includes that the first diode D1 and the second diode D2, described first capacitor filter 300 include the first electric capacity C1；The anode of described first diode D1 is connected with the negative electrode of described second diode D2, the link node of described first diode D1 and described second diode D2 is the input of described first rectification circuit 100, the negative electrode of described first diode D1 is connected with the positive pole of described first electric capacity C1, and the anode of described second diode D2 is connected with the negative pole of described first electric capacity C1.The positive pole of the first electric capacity C1 and the colelctor electrode of the first audion Q1 are connected simultaneously, and the negative pole of the first electric capacity C1 and the negative drive end of the first lamp bar 10 are connected, and the positive drive end of the first lamp bar 10 and the emitter stage of the first audion Q1 are connected.
When described backlight drive circuit is opened, first level output terminals A (the A end as shown in Figure 3) output supply voltage of described transformator T (transformator 800 as shown in Figure 2) extremely described first diode D1 and described second diode D2, when described supply voltage is in positive half period, described first diode D1 rectification, when described supply voltage is in negative half-cycle, described second diode D2 rectification.Described supply voltage input after rectified is to described first output capacitance C1, described supply voltage is filtered processing and being depressed at its positive pole output positive electricity the colelctor electrode of described first audion Q1 by described first output capacitance C1, is depressed into the negative drive end of described first lamp bar 10 at its negative output terminal output negative electricity.
When the base stage input high level of described 3rd audion Q3, described 3rd audion Q3 conducting, described second audion Q2 conducting, the output voltage of described accessory power supply VAUX is added to the base stage of described first audion Q1 through described second audion Q2 and described first resistance R1, described first audion Q1 conducting, the current path conducting formed between described first lamp bar and described transformer circuit 30, described first lamp bar 10 is bright.
When the base stage input low level of described 3rd audion Q3, described 3rd audion Q3 cut-off, described second audion Q2 cut-off, the output voltage of described accessory power supply VAUX cannot be added to the base stage of described first audion Q1 through described second audion Q2 and described first resistance R1, described first audion Q1 cut-off, the current path formed between described first lamp bar 10 and described transformer circuit 30 blocks, and described first lamp bar 10 goes out.
Backlight drive terminal circuit owing to the utility model proposes is the control opened and shut off that the current path by getting through and block between the first lamp bar 10 and transformer circuit 30 realizes to the first lamp bar 10.Therefore, rising edge and the trailing edge of the backlight drive circuit dimming waveform that the utility model proposes are the most precipitous, have widened the dimming scope of backlight drive circuit.Relative to prior art, technical solutions of the utility model have the advantages that dimming scope is wide.
Further, as it is shown on figure 3, described backlight drive circuit also includes that the second lamp bar 20, described transformer circuit 30 also include second subprime outfan B (B end as shown in Figure 3), the second rectification circuit 200 and the second capacitor filter 400；The input of described second rectification circuit 200 is connected with described second subprime outfan B, the outfan of described second rectification circuit 200 is connected with the input of described second capacitor filter 400, the outfan of described second capacitor filter 400 is connected with the power input of described light adjusting circuit 500, and the drive output of described light adjusting circuit 500 is connected with described second lamp bar 20.
Concrete, described second rectification circuit 200 includes that the 3rd diode D3 and the 4th diode D4, described second capacitor filter 400 include the second electric capacity C2；The anode of described 3rd diode D3 is connected with the negative electrode of described 4th diode D4, the input that link node is described second rectification circuit 200 of described 3rd diode D3 and described 4th diode D4；The negative electrode of described 3rd diode D3 is connected with the positive pole of described second electric capacity C2, and the anode of described 4th diode D4 is connected with the negative pole of described second electric capacity C2.The positive pole of the second electric capacity C2 also colelctor electrode with the first audion Q1 is connected simultaneously, and the negative pole of the second electric capacity C2 also negative drive end with the second lamp bar 20 is connected, and the positive drive end of the second lamp bar 20 and the emitter stage of the first audion Q1 are connected.
When described backlight drive circuit is opened, described first level output terminals A output supply voltage gives described first diode D1, described second diode D2；Described second subprime outfan B output supply voltage gives described 3rd diode D3 and described 4th diode D4.When described supply voltage is in positive half period, described first diode D1 and described 3rd diode D3 rectification, when described supply voltage is in negative half-cycle, described second diode D2 and described 4th diode D4 rectification.Described supply voltage after rectified is separately input into described first output capacitance C1 and described second output capacitance C2, described first output capacitance C1 and described second output capacitance C2 are filtered the colelctor electrode processed and its positive pole output positive electricity is depressed into described first audion Q1 respectively to described supply voltage, are depressed into described first lamp bar 10 and the negative drive end of described second lamp bar 20 at its negative pole output negative electricity.
When the base stage input high level of described 3rd audion Q3, described 3rd audion Q3 conducting, the output voltage of described accessory power supply VAUX is added to the base stage of described first audion Q1 through described second audion Q2 and described first resistance R1, described first audion Q1 conducting, the current path conducting formed between described first lamp bar 10 and described transformer circuit 30, described first lamp bar 10 is bright；The current path conducting formed between described second lamp bar 20 and described transformer circuit 30, described second lamp bar 20 is bright.
When the base stage input low level of described 3rd audion Q3, described 3rd audion Q3 cut-off, the output voltage of described accessory power supply VAUX cannot be added to the base stage of described first audion Q1 through described second audion Q2 and described first resistance R1, described first audion Q1 cut-off, the current path formed between described first lamp bar 10 and described transformer circuit 30 blocks, and described first lamp bar 10 goes out；The current path formed between described second lamp bar 20 and described transformer circuit 30 blocks, and described second lamp bar 20 goes out.
It should be noted that by the break-make duration controlling described light adjusting circuit 500, it is possible to achieve to described first lamp bar 10 and the regulation of the brightness of described second lamp bar 20.Because the switches switching frequency of described light adjusting circuit 500 is very fast, so, can't there is OFF state in eye-observation to described first lamp bar 10 and described second lamp bar 20, and simply brightness difference can occur because of the change of the break-make duration of light adjusting circuit 500.
It is worth mentioning that, described transformer circuit 30 also includes for flowing through described first lamp bar 10 and the equal current-sharing electric capacity C3 of described second lamp bar 20 electric current, first end of described current-sharing electric capacity C3 is connected with described second subprime outfan, and second end of described current-sharing electric capacity C3 is connected with the input of described second rectification circuit 200.
Set up the second rectification circuit the 200, second output capacitance C2 and the second lamp bar 20 so that described backlight drive circuit can apply in more electronic equipment.In addition, as required, can also set up the 3rd rectification circuit (not shown), the 3rd output capacitance (not shown) and the 3rd lamp article (not shown), the group number of this backlight drive circuit drivable lamp bar does not limits.
This utility model also proposes a kind of television set, this television set includes above-mentioned backlight drive circuit, the concrete structure of this backlight drive circuit is with reference to above-described embodiment, owing to this television set have employed whole technical schemes of above-mentioned all embodiments, the most at least having all beneficial effects that the technical scheme of above-described embodiment is brought, this is no longer going to repeat them.Wherein, this backlight drive circuit includes the first lamp bar 10 and provides the transformer circuit 30 of working power to described first lamp bar 10；Wherein, described transformer circuit 30 includes first level output terminals A (A end as shown in Figure 3), the first rectification circuit the 100, first capacitor filter 300 and light adjusting circuit 500；Described light adjusting circuit 500 has a power input, drive output and for receiving the signal input part of dim signal；The input of described first rectification circuit 100 is connected with described first level output terminals A, and the outfan of described first rectification circuit 100 is connected with the input of described first capacitor filter 300；The outfan of described first capacitor filter 300 is connected with the power input of described light adjusting circuit 500, and the drive output of described light adjusting circuit 500 is connected with described first lamp bar 10.
The foregoing is only preferred embodiment of the present utility model; not thereby the scope of the claims of the present utility model is limited; every under inventive concept of the present utility model; utilize the equivalent structure transformation that this utility model description and accompanying drawing content are made, or directly/be indirectly used in other relevant technical fields and be included in scope of patent protection of the present utility model.
Claims (10)
1. a backlight drive circuit, including the first lamp bar and to the transformer circuit of described first lamp bar offer working power, it is characterised in that described transformer circuit includes transformator, the first capacitor filter and light adjusting circuit；Described transformator is connected with described first capacitor filter, and described light adjusting circuit has a power input, drive output and for receiving the signal input part of dim signal；The outfan of described first capacitor filter is connected with the power input of described light adjusting circuit, and the drive output of described light adjusting circuit is connected with described first lamp bar；
Described light adjusting circuit includes switching tube and switch controlled circuit；The input of described switching tube is the power input of described light adjusting circuit, the outfan of described switching tube is the drive output of described light adjusting circuit, the controlled end of described switching tube is connected with the control end of described switch controlled circuit, the signal input part that input is described light adjusting circuit of described switch controlled circuit.
2. backlight drive circuit as claimed in claim 1, it is characterised in that be additionally provided with the first rectification circuit between described transformator and described first capacitor filter；
The input of described first rectification circuit is connected with the first secondary output end of described transformator, and the outfan of described first rectification circuit is connected with the input of described first capacitor filter.
3. backlight drive circuit as claimed in claim 2, it is characterized in that, described switching tube is the first audion, the input of the most described switching tube of current collection of described first audion, the outfan of the most described switching tube of transmitting of described first audion, the controlled end that base stage is described switching tube of described first audion.
4. backlight drive circuit as claimed in claim 3, it is characterised in that described switch controlled circuit includes the first resistance, the second resistance, the second audion, the 3rd audion and accessory power supply；First end of described first resistance is the control end of described switch controlled circuit, second end of described first resistance is connected with the colelctor electrode of described second audion, the emitter stage of described second audion is connected with the positive output end of described accessory power supply, the negative output terminal ground connection of described accessory power supply；The base stage of described second audion is connected with the first end of described second resistance, second end of described second resistance is connected with the colelctor electrode of described 3rd audion, described 3rd transistor emitter ground connection, the signal input part that base stage is described switch controlled circuit of described 3rd audion.
5. backlight drive circuit as claimed in claim 3, it is characterised in that described first rectification circuit includes that the first diode and the second diode, described first capacitor filter include the first electric capacity；The anode of described first diode is connected with the negative electrode of described second diode, the link node of described first diode and described second diode is the input of described first rectification circuit, the negative electrode of described first diode is connected with the positive pole of described first electric capacity, and the anode of described second diode is connected with the negative pole of described first electric capacity.
6. backlight drive circuit as claimed in claim 5, it is characterized in that, the positive pole of described first electric capacity also colelctor electrode with described first audion is connected, the negative pole of described first electric capacity also negative drive end with described first lamp bar is connected, and the positive drive end of described first lamp bar is connected with the emitter stage of described first audion.
7. backlight drive circuit as claimed in claim 2, it is characterised in that described backlight drive circuit also includes the second lamp bar, and described transformer circuit also includes the second rectification circuit and the second capacitor filter；The input of described second rectification circuit is connected with the second subprime outfan of described transformator, the outfan of described second rectification circuit is connected with the input of described second capacitor filter, the outfan of described second capacitor filter is connected with the power input of described light adjusting circuit, and the drive output of described light adjusting circuit is connected with described second lamp bar.
8. backlight drive circuit as claimed in claim 7, it is characterised in that described second rectification circuit includes that the 3rd diode and the 4th diode, described second capacitor filter include the second electric capacity；The anode of described 3rd diode is connected with the negative electrode of described 4th diode, described 3rd diode and the input that link node is described second rectification circuit of described 4th diode；The negative electrode of described 3rd diode is connected with the positive pole of described second electric capacity, and the anode of described 4th diode is connected with the negative pole of described second electric capacity；The positive pole of described second electric capacity also colelctor electrode with the first audion is connected, and the negative pole of described second electric capacity also negative drive end with the second lamp bar is connected, and the positive drive end of the second lamp bar and the emitter stage of the first audion are connected.
9. backlight drive circuit as claimed in claim 7, it is characterized in that, described transformer circuit also includes that current-sharing electric capacity, the first end of described current-sharing electric capacity are connected with described second subprime outfan, and the second end of described current-sharing electric capacity is connected with the input of described second rectification circuit.
10. a television set, it is characterised in that include the backlight drive terminal circuit as described in claim 1 to 9 any one.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620081255.XU CN205754936U (en) | 2016-01-27 | 2016-01-27 | Backlight drive circuit and television set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620081255.XU CN205754936U (en) | 2016-01-27 | 2016-01-27 | Backlight drive circuit and television set |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205754936U true CN205754936U (en) | 2016-11-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620081255.XU Expired - Fee Related CN205754936U (en) | 2016-01-27 | 2016-01-27 | Backlight drive circuit and television set |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN205754936U (en) |
-
2016
- 2016-01-27 CN CN201620081255.XU patent/CN205754936U/en not_active Expired - Fee Related
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20161130 Termination date: 20210127 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |