CN205946261U

CN205946261U - Multichannel LED flow equalize drive arrangement and backlight device

Info

Publication number: CN205946261U
Application number: CN201620863241.3U
Authority: CN
Inventors: 李锦乐; 宋贵奇
Original assignee: Shenzhen TCL New Technology Co Ltd
Current assignee: Shenzhen TCL New Technology Co Ltd
Priority date: 2016-08-10
Filing date: 2016-08-10
Publication date: 2017-02-08
Anticipated expiration: 2026-08-10

Abstract

The utility model discloses a multichannel LED flow equalize drive arrangement and backlight device, this multichannel LED flow equalize drive arrangement and include LLC half -bridge resonance power, first series -wound loop and second series -wound loop, and this LLC half -bridge resonance power has a secondary and the 2nd secondary, first series -wound loop at least by the component that flow equalizes, first rectifier element, third rectifier element, the 6th rectifier element and the 8th rectifier element with a secondary and the 2nd secondary series connection are formed, the second series -wound loop comprises second rectifier element, fourth rectifier element, the 5th rectifier element and the 7th rectifier element and a secondary and the 2nd secondary series connection at least, this multichannel LED flow equalizes drive arrangement and includes still that two at least series connection set up the LED banks on first series -wound loop, and two at least series connection set up the 2nd LED banks on the second series -wound loop. The utility model discloses a multichannel LED banks flow equalizes.

Description

Multi-channel LED current equalization driving means and back lighting device

Technical field

This utility model is related to backlight technology field, more particularly, to a kind of multi-channel LED current equalization driving means and back lighting device.

Background technology

LED light source has been widely used in non-active light-emitting display device.As back lighting, in order to realize multiple LED Lamp luminance proportion is it is often necessary to high-precision all stream drives so that the electric current flowing through multiple LED reaches balance.

Drive all using traditional approach currently for LED multi-path flow equalizing, the constant voltage module of such as Fig. 1 adds Buck voltage increase and current constant Module or as the constant voltage module of Fig. 2 adds Boost blood pressure lowering constant flow module, by the use of constant voltage module output as the constant current of multichannel DC/DC The input of circuit, then DC/DC circuit is individually done with current constant control, so it is easy to ensure the constant of multiplex output circuit, but Because the voltage of output voltage and LED is generally larger, the whole efficiency that therefore suffix cascades DC/DC constant-current circuit is not very high, And volume is big, relatively costly.

LLC half-bridge resonance power supply is little because of its switching loss, has very high conversion efficiency, has been successfully applied to LED-backlit and has driven In galvanic electricity road, driven with all stream realizing LED circuit, but due to being limited by components and parts and technique, be also only used for 1 tunnel, 2 tunnels at present Or 4 paths of LEDs lamp passage all stream drive it is difficult to drive more LED passages.

Content of the invention

Main purpose of the present utility model is to provide a kind of multi-channel LED current equalization driving means and back lighting device it is intended to reality All stream of existing multi-way LED lamp group circuit drives.

For achieving the above object, this utility model provides a kind of multi-channel LED current equalization driving means, including LLC half-bridge resonance Power supply, the first series loop and the second series loop, described LLC half-bridge resonance power supply has the first secondary windings and second subprime Winding；Described first series loop at least by equal fluid element, the first rectifier cell, the 3rd rectifier cell, the 6th rectifier cell and 8th rectifier cell is connected composition with described first secondary windings and second subprime windings in series；Described second series loop is at least By the second rectifier cell, the 4th rectifier cell, the 5th rectifier cell and the 7th rectifier cell and described first secondary windings and the Secondary stage windings in series connects composition；

Described multi-channel LED current equalization driving means also include at least two and are arranged in series in described first series loop One LED light group, and at least two be arranged in series the second LED light group in described second series loop.

Preferably, the first end of described first secondary windings is successively through described equal fluid element, described first rectifier cell, institute State the 8th rectifier cell to be connected with the second end of described second winding；The first end of described second subprime winding is successively through described 6th rectifier cell, described 3rd rectifier cell are connected with the second end of described first secondary windings；

The quantity of described first LED light group is two, and described two first LED light groups are arranged at described first rectifier cell And described 8th rectifier cell between；

Or, described two first LED light groups are arranged between described 6th rectifier cell and described 3rd rectifier cell；

Or, in described two first LED light groups one located at described first rectifier cell and described 8th rectifier cell Between, another is located between described 6th rectifier cell and described 3rd rectifier cell.

Preferably, the second end of described first secondary windings is successively through described 4th rectifier cell, described 5th rectification unit Part is connected with the first end of described second subprime winding；Second end of described second subprime winding is successively through described 7th rectification unit Part, described second rectifier cell are connected with the first end of described first secondary windings；

The quantity of described second LED light group is two, and described two second LED light groups are arranged at described 4th rectifier cell And described 5th rectifier cell between；

Or, described two second LED light groups are arranged between described 7th rectifier cell and described second rectifier cell；

Or, in described two second LED light groups one located at described 4th rectifier cell and described 5th rectifier cell Between, another is located between described 7th rectifier cell and described second rectifier cell.

The quantity of described first LED light group be three, between described first rectifier cell and described 8th rectifier cell and Between described 6th rectifier cell and described 3rd rectifier cell, one of both are provided with two described first LED light groups, Another one arranges described first LED light group；

Or, the quantity of described first LED light group is four, described first rectifier cell and described 8th rectifier cell it Between be respectively arranged with two described first LED light groups and described 6th rectifier cell and described 3rd rectifier cell between.

The quantity of described second LED light group be three, between described 4th rectifier cell and described 5th rectifier cell and Between described 7th rectifier cell and described second rectifier cell, one of both are provided with two described second LED light groups, Another one arranges described second LED light group；

Or, the quantity of described second LED light group is four, described 4th rectifier cell and described 5th rectifier cell it Between be respectively arranged with two described second LED light groups and described 7th rectifier cell and described second rectifier cell between.

Preferably, described multi-channel LED current equalization driving means also include the second electric capacity, the 3rd electric capacity, the 4th electric capacity and the 5th Electric capacity, described second electric capacity is connected in parallel between described first rectifier cell and described 8th rectifier cell；Described 3rd electricity Hold and be connected in parallel between the second rectifier cell and the 7th rectifier cell；Described 4th electric capacity is connected in parallel in described 3rd rectification Between element and described 6th rectifier cell；Described 5th electric capacity is connected in parallel in the 5th rectification described in described 4th rectifier cell Between element.

Preferably, described multi-channel LED current equalization driving means also include the second electric capacity, the 3rd electric capacity, the 4th electric capacity and the 5th Electric capacity, described second capacitances in series is connected between described first rectifier cell and described 8th rectifier cell；Described 3rd electricity Hold and be connected in series between the second rectifier cell and the 7th rectifier cell；Described 4th capacitances in series is connected to described 3rd rectification Between element and described 6th rectifier cell；Described 5th capacitances in series is connected to the 5th rectification described in described 4th rectifier cell Between element.

Preferably, described LLC half-bridge resonance power supply also includes transformator, the first driving switch, the second driving switch and LLC Controller；Described transformator has armature winding, the first secondary windings and second subprime winding；The first end of described armature winding With the outfan of described first driving switch and the input mutual connection of described second driving switch, the second end of described armature winding Through the 6th capacity earth, the controlled end of described first driving switch is connected with the first control end of described LLC controller, and described The input termination alternating current power supply of one driving switch；The controlled end of described second driving switch is controlled with the second of described LLC controller End processed connects, the output head grounding of described second driving switch.

Preferably, described LLC half-bridge resonance power supply also includes the inspection stream for detecting electric current in described first series loop Resistance and being connected with described inspection leakage resistance, in order to the described inspection current signal that detects of leakage resistance is fed back to described LLC control The feedback module of device.

This utility model also provides a kind of back lighting device, including multi-channel LED current equalization driving means as above, this multichannel LED all flows driving means and includes LLC half-bridge resonance power supply, the first series loop and the second series loop, this LLC half-bridge resonance electricity Source has the first secondary windings and second subprime winding；Described first series loop at least by equal fluid element, the first rectifier cell, 3rd rectifier cell, the 6th rectifier cell and the 8th rectifier cell are connected with described first secondary windings and second subprime windings in series Connect composition；Described second series loop is at least by the second rectifier cell, the 4th rectifier cell, the 5th rectifier cell and the 7th rectification Element is connected composition with described first secondary windings and second subprime windings in series；This multi-channel LED current equalization driving means also includes At least two are arranged in series the first LED light group in described first series loop, and at least two are arranged in series in described The second LED light group in two series loops.

This utility model multi-channel LED current equalization driving means are applied in back lighting device, and this multi-channel LED current equalization driving means is led to Cross by least two series connection the first LED light groups be arranged at least by equal fluid element, the first rectifier cell, the 3rd rectifier cell, the Six rectifier cells and the 8th rectifier cell are connected the first of composition and go here and there with described first secondary windings and second subprime windings in series On connection loop；And at least two series connection the first LED light group be arranged at least by the second rectifier cell, the 4th rectifier cell, the 5th Rectifier cell and the 7th rectifier cell are connected the second of composition and connect with described first secondary windings and second subprime windings in series Loop and be arranged in series the second LED light group in described second series loop by multiple LED load in series in the same circuit Upper so that the electric current flowing through each LED light group in series loop is all equal, meanwhile, effect through equal fluid element is so that flow through the The electric current of one series loop and the second series loop is all equal, finally achieves and all flows driving to multi-way LED lamp group, and then realizes The brightness of multiple LED light groups, the purpose of chroma equalization.

Brief description

Fig. 1 is the circuit structure block diagram of Buck booster type constant current LED drive circuit in prior art；

Fig. 2 is the circuit structure block diagram of Boost blood pressure lowering die mould constant current LED drive circuit in prior art；

Fig. 3 is the electrical block diagram of this utility model multi-channel LED current equalization driving means and back lighting device one embodiment；

Fig. 4 is the circuit structure signal of this utility model multi-channel LED current equalization driving means and another embodiment of back lighting device Figure.

Drawing reference numeral explanation：

Label	Title	Label	Title	Label	Title
						10	LLC half-bridge resonance power supply	N1	Armature winding	D8	8th rectifier cell
11	LLC controller	N2	First secondary windings	R1	Inspection leakage resistance
						12	First driving switch	N3	Second subprime winding	C1	First electric capacity
13	Second driving switch	D1	First rectifier cell	C2	Second electric capacity
						14	Feedback module	D2	Second rectifier cell	C3	3rd electric capacity
141	Error amplifier	D3	3rd rectifier cell	C4	4th electric capacity
						U1	Optocoupler	D4	4th rectifier cell	C5	5th electric capacity
Q1	First metal-oxide-semiconductor	D5	5th rectifier cell	C6	6th electric capacity
						Q2	Second metal-oxide-semiconductor	D6	6th rectifier cell
T1	Transformator	D7	7th rectifier cell

The realization of this utility model purpose, functional characteristics and advantage will be described further in conjunction with the embodiments referring to the drawings.

Specific embodiment

Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is carried out Clearly and completely describe it is clear that described embodiment is only a part of embodiment of the present utility model, rather than all Embodiment.Based on the embodiment in this utility model, those of ordinary skill in the art are not making creative work premise Lower obtained every other embodiment, broadly falls into the scope of this utility model protection.

It is to be appreciated that the directional instruction (such as up, down, left, right, before and after ...) of institute in this utility model embodiment It is only used for explaining the relative position relation between each part, motion conditions etc. under a certain particular pose (as shown in drawings), such as When really this particular pose changes, then directionality instruction also correspondingly changes therewith.

In addition, the description being related to " first ", " second " etc. in this utility model is only used for describing purpose, and it is not understood that For indicating or implying its relative importance or the implicit quantity indicating indicated technical characteristic.Thus, define " first ", The feature of " second " can be expressed or implicitly include at least one this feature.In addition, the technical side between each embodiment Case can be combined with each other, but must be capable of by those of ordinary skill in the art based on, when the combination of technical scheme Will be understood that the combination of this technical scheme does not exist when appearance is conflicting or cannot realize, also do not require in this utility model Protection domain within.

This utility model provides a kind of multi-channel LED current equalization driving means.

With reference to Fig. 3, in one embodiment, the utility model proposes multi-channel LED current equalization driving means to include LLC half-bridge humorous Shake power supply 10, the first series loop and the second series loop.

Specifically, this LLC half-bridge resonance power supply has the first secondary windings N2 and second subprime winding N3, by for the first time Level winding N2 and second subprime winding N3 exports the supply voltage of positive and negative alternate.

First series loop is at least by equal fluid element, the first rectifier cell D1, the 3rd rectifier cell D3, the 6th rectifier cell D6 and the 8th rectifier cell D8 and described first secondary windings N2 and second subprime winding N3 is connected in series composition.Rectifier cell D1, D3, D6, D8 are used for be transformed into after DC source through the alternating current power supply that LLC half-bridge resonance power supply 10 exports, and export to each LED load energy supply.Wherein, equal fluid element is used for realizing flowing through the first rectifier cell D1 being attached thereto and the second rectifier cell D2 Electric current is equal.This equal fluid element can be realized using electric capacity, the first electric capacity C1 as shown in Figure 3, balanced special using the ampere-second of electric capacity Property realizes current balance function.

Second series loop is at least by the second rectifier cell D2, the 4th rectifier cell D4, the 5th rectifier cell D5 and the 7th Rectifier cell D7 and described first secondary windings N2 and second subprime winding N3 is connected in series composition.Rectifier cell D2, D4, D5, D7 is used for be transformed into after DC source through the alternating current power supply that LLC half-bridge resonance power supply 10 exports, and exports and supplies to each LED load Energy.

Wherein, described first series loop has at least been arranged in series two the first LED light groups, described second series loop On be at least arranged in series two the second LED light groups.It should be noted that in the first series loop and second series loop LED light group quantity will be corresponding to, then can adopt two the first LED light groups and two the second LED light groups, or, can adopt Three the first LED light groups and three the second LED light groups etc., quantity does not limit.

During work, when LLC half-bridge resonance power supply 10 is just output as by the first secondary windings N2 and second subprime winding N3 During half cycle, the electric current of the first end of the first end of the first secondary windings N2 and second subprime winding N3 is just now rectifier cell D1, D3, D6, D8 turn on, and the first secondary windings N2 and second subprime winding N3 is exported by corresponding rectifier cell D1, D3, D6, D8 Voltage rectified after export, be supplied to the first LED light group to drive the first LED light group to light.

When LLC half-bridge resonance power supply 10 is output as negative half period by the first secondary windings N2 and second subprime winding N3, The electric current at second end of second end of the first secondary windings N2 and second subprime winding N3 be just, now rectifier cell D2, D4, D5, D7 turn on, the voltage that the first secondary windings N2 and second subprime winding N3 is exported by corresponding rectifier cell D2, D4, D5, D7 Export after rectified, be supplied to the second LED light group, to drive the second LED light group to light.

It should be noted that in LLC half-bridge resonance power supply 10, defeated by the first secondary windings N2 and second subprime winding N3 Going out the positive half cycle of electric current and negative half period is symmetrical structure, namely the current amplitude of positive half cycle and negative half period is equal.According to equal The current balance function of fluid element, namely the ampere-second equilibrium response of electric capacity, in a cycle, the average current flowing through electric capacity is zero. So that to flow through the first rectifier cell D1 equal with the second rectifier cell D2 electric current in the presence of the first electric capacity C1, and because the One rectifier cell D1 is to be connected in series relation with rectifier cell D3, D6, D8 and the first LED light group, meanwhile, the second rectifier cell D2 It is to be connected in series relation with rectifier cell D4, D5, D7 and the second LED light group, therefore flow through the electric current and second of the first series loop The electric current of series loop is also equal, so so that the electric current flowing through each LED light group is all equal, it is achieved thereby that to multichannel The purpose of LED light group all stream.

In a preferred embodiment of the first series loop, the first end of described first secondary windings N2 is successively through described equal Fluid element, described first rectifier cell D1, described 8th rectifier cell D8 are connected with second end of described second winding N3；Institute The first end stating second subprime winding N3 is successively through described 6th rectifier cell D6, described 3rd rectifier cell D3 and described first Second end of secondary windings N2 connects.

In the present embodiment, the quantity of described first LED light group can be two, three or four, even more many.

Specifically, when the quantity of the first LED light group is two, described two first LED light groups may be disposed at described the Between one rectifier cell D1 and described 8th rectifier cell D8, for example, LED1, LED2 as shown in Figure 3.

Or, described two first LED light groups may be disposed at described 6th rectifier cell D6 and described 3rd rectifier cell Between D3.For example, LED5 and LED6 as shown in Figure 3.

Or, in described two first LED light groups one located at described first rectifier cell D1 and described 8th rectification Between element D8, another is located between described 6th rectifier cell D6 and described 3rd rectifier cell D3.Specifically, described two In individual first LED light group one located at the first LED between described first rectifier cell D1 and described 8th rectifier cell D8 Group can be any one in LED1 and LED2；Between described 6th rectifier cell D6 and described 3rd rectifier cell D3 One LED light group can be any one in LED5 and LED6.

When LLC half-bridge resonance power supply 10 is output as positive half cycle by the first secondary windings N2 and second subprime winding N3, The electric current of the first end of the first end of the first secondary windings N2 and second subprime winding N3 is just, the first series loop obtains electricity Pressure, now rectifier cell D1, D3, D6, D8 conducting, corresponding rectifier cell D1, D3, D6, D8 are by the first secondary windings N2 and the The supply voltage of secondary stage winding N3 output exports, to drive any two-way in LED1, LED2, LED5, LED6 after carrying out rectification Work.

When the quantity of the first LED light group is three, described first rectifier cell D1 and described 8th rectifier cell D8 it Between and described 6th rectifier cell D6 and described 3rd rectifier cell D3 between, one of both are provided with two described first LED light group, another one is provided with described first LED light group.

Specifically, if being provided with two the first LED light groups between the first rectifier cell D1 and described 8th rectifier cell D8, For example, LED1 and LED2 as shown in Figure 3, then setting between described 6th rectifier cell D6 and described 3rd rectifier cell D3 One the first LED light group can be any one in LED5 or LED6；If described 6th rectifier cell D6 and described 3rd rectification Be provided with two the first LED light groups between element D3, for example, LED5 and LED6 as shown in Figure 3, then the first rectifier cell D1 with Being provided with first LED light group between described 8th rectifier cell D8 can be any one in LED1 and LED2.

When LLC half-bridge resonance power supply 10 is output as positive half cycle by the first secondary windings N2 and second subprime winding N3, The electric current of the first end of the first end of the first secondary windings N2 and second subprime winding N3 is just, the first series loop obtains electricity Pressure, now rectifier cell D1, D3, D6, D8 conducting, corresponding rectifier cell D1, D3, D6, D8 are by the first secondary windings N2 and the The supply voltage of secondary stage winding N3 output exports, to drive any three tunnels in LED1, LED2, LED5, LED6 after carrying out rectification Work.

When the quantity of the first LED light group is four, described first rectifier cell D1 and described 8th rectifier cell D8 it Between be respectively arranged with two described first LED light groups and described 6th rectifier cell D6 and described 3rd rectifier cell D3 between.

Specifically, it is provided with two the first LED light groups, example between the first rectifier cell D1 and described 8th rectifier cell D8 As, LED1 and LED2 as shown in Figure 3, and described 6th rectifier cell D6 and described 3rd rectifier cell D3 is provided with two the One LED light group, for example, LED5 and LED6 as shown in Figure 3.

When LLC half-bridge resonance power supply 10 is output as positive half cycle by the first secondary windings N2 and second subprime winding N3, The electric current of the first end of the first end of the first secondary windings N2 and second subprime winding N3 is just, the first series loop obtains electricity Pressure, now rectifier cell D1, D3, D6, D8 conducting, corresponding rectifier cell D1, D3, D6, D8 are by the first secondary windings N2 and the The supply voltage of secondary stage winding N3 output exports, to drive the first LED light group LED1, LED2, LED5, LED6 after carrying out rectification Work.

In a preferred embodiment of the second series loop, second end of described first secondary windings N2 is successively through described Four rectifier cell D4, described 5th rectifier cell D5 are connected with the first end of described second subprime winding N3；Described second subprime Second end of winding N3 is successively through described 7th rectifier cell D7, described second rectifier cell D2 and described first secondary windings N2 First end connect；

In the present embodiment, the quantity of described second LED light group can be two, three or four, even more many.

Specifically, when the quantity of described second LED light group is two, described two second LED light groups are arranged at described Between 4th rectifier cell D4 and described 5th rectifier cell D5, for example, as LED7 and LED8 in Fig. 3.

Or, described two second LED light groups are arranged at described 7th rectifier cell D7 and described second rectifier cell D2 Between, for example, as LED3 and LED4 in Fig. 3.

Or, in described two second LED light groups one located at described 4th rectifier cell D4 with described 5th rectification unit Between part D5, another is between described 7th rectifier cell D7 and described second rectifier cell D2.

Specifically, in described two second LED light groups one located at described 4th rectifier cell D4 and described 5th rectification The second LED light group between element D5 can be any one in LED7 and LED8；Another is located at described 7th rectifier cell D7 The second LED light group and described second rectifier cell D2 between can be any one in LED3 and LED4.

When LLC half-bridge resonance power supply 10 is output as negative half period by the first secondary windings N2 and second subprime winding N3, The electric current at second end of second end of the first secondary windings N2 and second subprime winding N3 is just, the second series loop obtains electricity Pressure, now rectifier cell D2, D4, D5, D7 conducting, corresponding rectifier cell D2, D4, D5, D7 are by the first secondary windings N2 and the The supply voltage of secondary stage winding N3 output carries out exporting after rectification, with drive LED3 in the second LED light group, LED4, LED7, Any two-way work in LED8.

When the quantity of the second LED light group is for three, described 4th rectifier cell D4 and described 5th rectifier cell D5 Between and described 7th rectifier cell D7 and described second rectifier cell D2 between, one of both are provided with two described Two LED light groups, another one arranges described second LED light group.

Specifically, if being provided with two the second LED light groups between the 4th rectifier cell D4 and described 5th rectifier cell D5, For example, LED5 and LED6 as described in Figure 3, then be provided between described second rectifier cell D2 and described 7th rectifier cell D7 Any one second LED light group, for example, LED3 or LED4 as shown in Figure 3；If described second rectifier cell D2 and the described 7th It is provided with two the second LED light groups between rectifier cell D7, for example, LED3 and LED4 as shown in Figure 3, then the 4th rectifier cell Be provided with second LED light group between D4 and described 5th rectifier cell D5, can for LED7 and LED8 any one.

When LLC half-bridge resonance power supply 10 is output as negative half period by the first secondary windings N2 and second subprime winding N3, The electric current at second end of second end of the first secondary windings N2 and second subprime winding N3 is just, the second series loop obtains electricity Pressure, now rectifier cell D2, D4, D5, D7 conducting, corresponding rectifier cell D2, D4, D5, D7 are by the first secondary windings N2 and the The supply voltage of secondary stage winding N3 output carries out exporting after rectification, with drive LED3 in the second LED light group, LED4, LED7, Any three tunnel work in LED8.

When the quantity of described second LED light group is four, described 4th rectifier cell D4 and described 5th rectifier cell It is respectively arranged with two described second LED and described 7th rectifier cell D7 and described second rectifier cell D2 between D5 Group.

Specifically, it is provided with two the second LED light groups, example between described 7th rectifier cell D7 the second rectifier cell D2 As, LED3 and LED4 as shown in Figure 3, and described 4th rectifier cell D4 and described 5th rectifier cell D5 is provided with two the Two LED light groups, for example, LED7 and LED8 as shown in Figure 3.

When LLC half-bridge resonance power supply 10 is output as negative half period by the first secondary windings N2 and second subprime winding N3, The electric current at second end of second end of the first secondary windings N2 and second subprime winding N3 is just, the second series loop obtains electricity Pressure, now rectifier cell D2, D4, D5, D7 conducting, corresponding rectifier cell D2, D4, D5, D7 are by the first secondary windings N2 and the The voltage of secondary stage winding N3 output exports, to drive LED light group LED3, LED4, LED7, LED8 to light after carrying out rectification.

It is understood that in positive half cycle, the first end through the first secondary windings N2 for the electric current, equal fluid element, first whole Fluid element D1, the first LED light group LED1, the second LED light group LED2, the 5th LED light group LED5, the 7th LED light group LED7, the 8th Rectifier cell D8, second subprime winding N3, the 6th rectifier cell D6 and the 3rd rectifier cell D3 flow to the first secondary windings N2's Second end, so, by LED light group LED1, LED2, LED5, LED6 formed the first series loop so that flow through LED light group LED1, The electric current of LED2, LED5, LED6 is equal, in negative half period, the second end through the first secondary windings N2 for the electric current, the 4th rectifier cell D4, the 5th rectifier cell D5 and second subprime winding N3, the 7th rectifier cell D7, LED3, the 4th LED light group LED4, the 6th LED Lamp group LED6, the 8th LED light group LED8, the second rectifier cell D2 and equal fluid element flow to the first end of the first secondary windings N2, So, by LED light group LED3, LED4, LED7, LED8 formed the second series loop so that flow through LED light group LED3, LED4, The electric current of LED7, LED8 is equal, simultaneously as the current balance function of the first electric capacity C1 is so that flow through by the first rectifier cell D1 group The series loop becoming is finally equal with the electric current of the series loop being made up of the second rectifier cell D2.So that flowing through each The electric current of LED light group is all equal, it is achieved thereby that the purpose to multi-channel LED lamp group all stream.

With reference to Fig. 4, in a preferred embodiment, the common end grounding of LED1 and LED2；And/or, described LED7 and LED8 Common end grounding.The i.e. common end grounding of LED1 and described LED2；Or, the common end grounding of described LED7 and LED8, or The common end grounding of person LED1 and LED2, and the common end grounding of described LED7 and LED8.

The common end grounding of LED3 and LED4；And/or, the common end grounding of described LED5 and LED6.I.e. LED3 with described The common end grounding of LED4；Or, the common end grounding of described LED5 and LED6, or the common end grounding of LED3 and LED4, And the common end grounding of described LED5 and LED6.

In above-described embodiment, this LLC half-bridge resonance power supply 10 can be driven using transformator T1, the first driving switch 12, second Move switch 13 and LLC controller 11 to realize, described transformator T1 also has armature winding N1, the first secondary windings N2 and second Secondary windings N3, the first secondary windings N2 and second subprime are around the first secondary windings N2 and of as LLC half-bridge resonance power supply Secondary stage winding N3.Wherein, the outfan of the first end of described armature winding N1 and described first driving switch 12 and described the The common port of the input of two driving switch 13 connects, the second end the 6th electric capacity C6 ground connection of described armature winding N1, described The controlled end of the first driving switch 12 is connected with the first control end of described LLC controller 11, described first driving switch 12 Input termination power；The controlled end of described second driving switch 13 is connected with the second control end of described LLC controller 11, described The output head grounding of the second driving switch 13.Second end of the first end of armature winding N1 and described first secondary windings N2 and institute State the second end Same Name of Ends each other of second subprime winding N3.Wherein, described first driving switch 12 is preferably the first metal-oxide-semiconductor Q1； Described second driving switch 13 is preferably the second metal-oxide-semiconductor Q2, and the drain electrode of described first metal-oxide-semiconductor Q1 is connected with power supply, and described first The source electrode of metal-oxide-semiconductor is connected with the drain electrode of the first metal-oxide-semiconductor Q1, and the grid of described first metal-oxide-semiconductor Q1 is being subject to of the first driving switch 12 Control end；The source ground of described second metal-oxide-semiconductor Q2, the grid of described second metal-oxide-semiconductor Q2 is the controlled end of the second driving switch 13.

During work, LLC controller 11 passes through to control the complementary conducting of the first metal-oxide-semiconductor Q1 and described second metal-oxide-semiconductor Q2 and cuts Only, carry out driving transformer T1 the alternating voltage of input be converted to suitable voltage output to lead to each LED light group for each LED light group Road provides energy, thus driving LED light group to work.

Control the complementary conducting of the first metal-oxide-semiconductor Q1 and the second metal-oxide-semiconductor Q2 when LLC controller 11 output pwm control signal thus T1 level of transformator is made to export in positive half cycle, the first end of the first end of the first secondary windings N2 and second subprime winding N3 Electric current is just, now, by the first secondary windings N2 and second subprime winding N3 output supply voltage to the first series loop, with Drive the first series loop work.

Control the complementary conducting of the first metal-oxide-semiconductor Q1 and the second metal-oxide-semiconductor Q2 when LLC controller 11 output pwm control signal thus T1 level of transformator is made to export in negative half period, second end of second end of the first secondary windings N2 and second subprime winding N3 Electric current is just, now, by the first secondary windings N2 and second subprime winding N3 output supply voltage to the first series loop, with Drive the second series loop work.

It should be noted that LLC half-bridge resonance power supply 10 has ZVT characteristic, it is to avoid LLC half-bridge resonance electricity So that output increases, the work efficiency of device is lifted source 10 internal loss, and due to there is no switching loss, switch Frequency can also improve, thus reducing the volume of magneticss, can also reduce the capacity of filter capacitor simultaneously；Additionally reduce Output inductor, the resonant inductance of this LLC half-bridge resonance power supply 10 can be undertaken using the leakage inductance of transformator T1, this Sample, decreases the number of capacitive element and magneticss, thus reducing circuit cost.

In addition it is also necessary to illustrate, LLC half-bridge resonance power supply 10 also has resonant inductance and magnetizing inductance, in this reality Apply in example, this resonant inductance and magnetizing inductance are all integrated in transformator T1, and by the use of the leakage inductance of transformator T1 as resonance electricity Sense, and by the use of the magnetizing inductance of transformator T1 as magnetizing inductance to reduce magneticss number.

Further, described LLC half-bridge resonance power supply 10 is also included for detecting electric current in described first series loop Inspection leakage resistance R1 and be connected with described inspection leakage resistance R1, the current signal in order to described inspection leakage resistance R1 is detected feeds back to The feedback module 14 of described LLC controller.

Specifically, described inspection leakage resistance R1 is connected between described LED1 and ground.

By examining leakage resistance R1, the current signal flowing through LED light group is exported anti-to LLC controller 11 by feedback module 14 Feedback receiving terminal, so that LLC controller 11 controls to adjust the turn-on frequency of the first metal-oxide-semiconductor Q1 and the second metal-oxide-semiconductor Q2 controlling transformation The size of device T1 output current, thus the electric current of stabilizing transformer T1 output is it is ensured that the electric current in LED light group is a steady state value.

In the present embodiment, feedback module 14 includes optocoupler U1 and error amplifier 141, described error amplifier 141 defeated Enter end be connected with the common port of described inspection leakage resistance R1 and the first LED light group LED1, the outfan of described error amplifier 141 and The input of described optocoupler U1 connects, and the outfan of described optocoupler U1 is the outfan of described feedback module 14.

Specifically, optocoupler U1 includes light emitting diode and phototriode, the negative electrode of light emitting diode and error amplifier Outfan connect, the colelctor electrode of phototriode is connected with the feedback reception end of LLC controller 11.

When detection signal amplifies output to optocoupler U1 through error amplifier 141, the light emitting diode triggering of optocoupler U1 is led Leading to thus driving phototriode to turn on, realizing the unidirectional output of detection signal.

It should be noted that when electric current flows through inspection leakage resistance R1, it will produce a voltage drop on inspection leakage resistance R1 VRS, this voltage VRS to flow through inspection leakage resistance R1 electric current be directly proportional, voltage VRS through error amplifier 141 amplification after export to Optocoupler U1, is transmitted to the feedback reception end of LLC controller 11 by optocoupler U1 isolation, so, is achieved that to each LED light group electricity The monitoring of stream.

Based on above-described embodiment, with reference to Fig. 3, described multi-channel LED current equalization driving means still further comprise the second electric capacity C2, Second electric capacity C3, the 4th electric capacity C4 and the 5th electric capacity C5, described second electric capacity C2 is connected in series in described first rectifier cell D1 And described 8th rectifier cell D8 between；Described 3rd electric capacity C3 is connected in series in the second rectifier cell D2 and the 7th rectifier cell Between D7；Described 4th electric capacity C4 is connected in series between described 3rd rectifier cell D3 and described 6th rectifier cell D6；Institute State the 5th electric capacity C5 to be connected in series in described in described 4th rectifier cell D4 between the 5th rectifier cell D5.Wherein, the second electric capacity C2, the 3rd electric capacity C3, the 4th electric capacity C4 and the 5th electric capacity C5 are used for the DC source after rectification being filtered process.

This utility model also provides a kind of back lighting device, and this back lighting device includes above-mentioned multi-channel LED current equalization driving means；Institute The detailed construction stating multi-channel LED current equalization driving means can refer to above-described embodiment, and here is omitted；It is understood that by In employing above-mentioned multi-channel LED current equalization driving means in back lighting device, therefore, the embodiment of this back lighting device include above-mentioned many Paths of LEDs all flows whole technical schemes of driving means whole embodiments, and the technique effect being reached is also identical, and here is not Repeat again.

These are only preferred embodiment of the present utility model, not thereby limit the scope of the claims of the present utility model, every The equivalent structure made using this utility model description and accompanying drawing content or equivalent flow conversion, or be directly or indirectly used in Other related technical fields, are all included in the same manner in scope of patent protection of the present utility model.

Claims

1. a kind of multi-channel LED current equalization driving means are it is characterised in that include LLC half-bridge resonance power supply, the first series loop and the Two series loops, described LLC half-bridge resonance power supply has the first secondary windings and second subprime winding；Described first series loop At least by equal fluid element, the first rectifier cell, the 3rd rectifier cell, the 6th rectifier cell and the 8th rectifier cell and described first Secondary windings and second subprime windings in series connect composition；Described second series loop is at least by the second rectifier cell, the 4th whole Fluid element, the 5th rectifier cell and the 7th rectifier cell are connected group with described first secondary windings and second subprime windings in series Become；

Described multi-channel LED current equalization driving means also include at least two be arranged in series in described first series loop first LED light group, and at least two be arranged in series the second LED light group in described second series loop.

2. multi-channel LED current equalization driving means as claimed in claim 1 it is characterised in that described first secondary windings first End is successively through described equal fluid element, described first rectifier cell, described 8th rectifier cell and the second of described second winding End connects；The first end of described second subprime winding successively through described 6th rectifier cell, described 3rd rectifier cell with described Second end of the first secondary windings connects；

The quantity of described first LED light group is two, and described two first LED light groups are arranged at described first rectifier cell and institute State between the 8th rectifier cell；

Or, in described two first LED light groups one between described first rectifier cell and described 8th rectifier cell, Another is located between described 6th rectifier cell and described 3rd rectifier cell.

3. multi-channel LED current equalization driving means as claimed in claim 1 it is characterised in that described first secondary windings second End is connected with the first end of described second subprime winding through described 4th rectifier cell, described 5th rectifier cell successively；Described Second end of second subprime winding is successively through described 7th rectifier cell, described second rectifier cell and described first secondary windings First end connect；

The quantity of described second LED light group is two, and described two second LED light groups are arranged at described 4th rectifier cell and institute State between the 5th rectifier cell；

Or, in described two second LED light groups one located between described 4th rectifier cell and described 5th rectifier cell, Another is located between described 7th rectifier cell and described second rectifier cell.

4. multi-channel LED current equalization driving means as claimed in claim 1 it is characterised in that described first secondary windings first End is successively through described equal fluid element, described first rectifier cell, described 8th rectifier cell and the second of described second winding End connects；The first end of described second subprime winding successively through described 6th rectifier cell, described 3rd rectifier cell with described Second end of the first secondary windings connects；

The quantity of described first LED light group is three, between described first rectifier cell and described 8th rectifier cell and described Between 6th rectifier cell and described 3rd rectifier cell, one of both are provided with two described first LED light groups, in addition One described first LED light group of one setting；

Or, the quantity of described first LED light group is four, between described first rectifier cell and described 8th rectifier cell and It is respectively arranged with two described first LED light groups between described 6th rectifier cell and described 3rd rectifier cell.

5. multi-channel LED current equalization driving means as claimed in claim 1 it is characterised in that described first secondary windings second End is connected with the first end of described second subprime winding through described 4th rectifier cell, described 5th rectifier cell successively；Described Second end of second subprime winding is successively through described 7th rectifier cell, described second rectifier cell and described first secondary windings First end connect；

The quantity of described second LED light group is three, between described 4th rectifier cell and described 5th rectifier cell and described Between 7th rectifier cell and described second rectifier cell, one of both are provided with two described second LED light groups, in addition One described second LED light group of one setting；

Or, the quantity of described second LED light group is four, between described 4th rectifier cell and described 5th rectifier cell and It is respectively arranged with two described second LED light groups between described 7th rectifier cell and described second rectifier cell.

6. the multi-channel LED current equalization driving means as described in any one of claim 1 to 5 are it is characterised in that described LED multi-path is equal Stream driving means also include the second electric capacity, the 3rd electric capacity, the 4th electric capacity and the 5th electric capacity, and described second capacitances in series is connected to institute State between the first rectifier cell and described 8th rectifier cell；Described 3rd capacitances in series is connected to the second rectifier cell and the 7th Between rectifier cell；Described 4th capacitances in series is connected between described 3rd rectifier cell and described 6th rectifier cell；Institute State the 5th capacitances in series to be connected to described in described 4th rectifier cell between the 5th rectifier cell.

7. the multi-channel LED current equalization driving means as described in any one of claim 1 to 5 are it is characterised in that described LLC half-bridge is humorous The power supply that shakes also includes transformator, the first driving switch, the second driving switch and LLC controller；Described transformator have primary around Group, the first secondary windings and second subprime winding；The first end of described armature winding and the outfan of described first driving switch And the input mutual connection of described second driving switch, the second end the 6th capacity earth of described armature winding, described first drive The controlled end of dynamic switch is connected with the first control end of described LLC controller, the input termination exchange of described first driving switch Power supply；The controlled end of described second driving switch is connected with the second control end of described LLC controller, described second driving switch Output head grounding.

8. multi-channel LED current equalization driving means as claimed in claim 7 are it is characterised in that described LLC half-bridge resonance power supply also wraps Include for detecting in described first series loop the inspection leakage resistance of electric current and being connected with described inspection leakage resistance, in order to flow described inspection Resistance detection to current signal feed back to the feedback module of described LLC controller.

9. a kind of back lighting device is it is characterised in that the multi-channel LED current equalization including as described in claim 1 to 8 any one drives Device.