CN207266333U - A kind of multi-channel LED current equalization drive circuit - Google Patents
A kind of multi-channel LED current equalization drive circuit Download PDFInfo
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- CN207266333U CN207266333U CN201720887260.4U CN201720887260U CN207266333U CN 207266333 U CN207266333 U CN 207266333U CN 201720887260 U CN201720887260 U CN 201720887260U CN 207266333 U CN207266333 U CN 207266333U
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Abstract
This application discloses a kind of multi-channel LED current equalization drive circuit,Including driving transformer,Balance inductance and two-way rectification circuit,The driving transformer includes first vice-side winding and second vice-side winding of the output phase with alternating voltage,The balance inductance includes inductance battery core,And the first inductor winding and the second inductor winding that two numbers of turn that are wound in the inductance battery core are identical,The Same Name of Ends of first vice-side winding is electrically connected the Same Name of Ends of first inductor winding,The Same Name of Ends of second vice-side winding is electrically connected the different name end of second inductor winding,The different name end of first vice-side winding and the different name end of first inductor winding are electrically connected two voltage input ends of first via rectification circuit,The Same Name of Ends of the different name end of second vice-side winding and second inductor winding is electrically connected two voltage input ends of No. second rectification circuit.This programme circuit structure is simple, without increasing constant-current circuit, significant effect and reduces cost.
Description
Technical field
It the utility model is related to LED drive circuit technical field, and in particular to a kind of multi-channel LED current equalization drive circuit.
Background technology
LED (Light-Emitting Diode, light emitting diode), is a kind of semiconductor that can convert electrical energy into luminous energy
Electronic component.The purposes of LED is quite varied, and indicator light, display board etc. are mainly used at the beginning of development, with technology it is continuous into
Step, LED are gradually widely used on the display devices such as display, television set.
With the development of demand and science and technology, LED display device from initial 15 cun, 17 cun by now 70 cun and with
On, in the LED display device below 70 cun, two paths of LED lamp group can meet display demand, but the large-size screen monitors of 70 cun and the above
LED display device, traditional two paths of LED show the requirement that can not meet large-sized LED display device, therefore present 70 cun
And the large-size screen monitors LED display device of the above, it generally will carry out auxiliary using 4 paths of LEDs lamp groups and show.
Present many display device production firms are typically all one group in parallel respectively in original two paths of LED lamp group
LED light group, 4 paths of LEDs lamp groups of composition are to meet the requirement of large-sized LED display device, but effect is all bad, refer to figure
1, Fig. 1 is the drive circuit of the two paths of LED lamp group of the prior art, when two LED light groups voltage difference with it is larger when, voltage it is low that
The linear constant current circuit power consumption of group is big, and fever is serious, poor reliability, and increases that constant-current circuit cost is also high, and one specific
Experimental data show, when the voltage difference of two paths of LED lamp group is 2%, the difference between current of two paths of LED lamp group can reach 10% or
More than 10%.
Utility model content
The purpose of this utility model is that a kind of multi-channel LED current equalization drive circuit is proposed, to solve above technical problem.
For this purpose, the utility model uses following technical scheme：
A kind of multi-channel LED current equalization drive circuit provided by the utility model, including driving transformer, balance inductance and two-way
Rectification circuit；
The driving transformer includes first vice-side winding and second vice-side winding of the output phase with alternating voltage；It is described flat
Weighing apparatus inductance includes inductance battery core, and the first inductor winding and the second electricity that two numbers of turn being wound in the inductance battery core are identical
Feel winding；
The Same Name of Ends of first vice-side winding is electrically connected the Same Name of Ends of first inductor winding；Second secondary around
The Same Name of Ends of group is electrically connected the different name end of second inductor winding；
The different name end of first vice-side winding and the different name end of first inductor winding are electrically connected first via rectified current
Two voltage input ends on road；The Same Name of Ends of the different name end of second vice-side winding and second inductor winding is electrically connected second
Two voltage input ends of road rectification circuit.
Preferably, the first via rectification circuit driving has LED1 lamps group and LED2 lamp groups；
The first via rectification circuit include capacitance Cd1, rectifier diode D1, rectifier diode D2, rectifier diode D3,
Rectifier diode D4, capacitance C1 and capacitance C2；
The different name end of first inductor winding is electrically connected the cathode of capacitance Cd1, the different name end of first vice-side winding
It is electrically connected the cathode of rectifier diode D2 and the anode of rectifier diode D4；
The anode of capacitance Cd1 is electrically connected the cathode of rectifier diode D1 and the anode of rectifier diode D3；Rectification two
The anode of pole pipe D1 is electrically connected the cathode of capacitance C2 and the positive input terminal of LED2 lamp groups；The anode of capacitance C2 is electrically connected respectively
Connect the cathode of the negative input end of LED1 lamp groups, the anode of capacitance C1, the cathode of rectifier diode D3 and rectifier diode D4；Capacitance
The cathode of C1 is electrically connected the anode of rectifier diode D2 and the positive input terminal of LED1 lamp groups.
Preferably, No. second rectification circuit driving has LED3 lamps group and LED4 lamp groups；
No. second rectification circuit include capacitance Cd2, rectifier diode D5, rectifier diode D6, rectifier diode D7,
Rectifier diode D8, capacitance C3 and capacitance C4；
The Same Name of Ends of second inductor winding is electrically connected the cathode of capacitance Cd2, the different name end of second vice-side winding
It is electrically connected the cathode of rectifier diode D6 and the anode of rectifier diode D8；
The anode of capacitance Cd2 is electrically connected the cathode of rectifier diode D5 and the anode of rectifier diode D7；Rectification two
The anode of pole pipe D5 is electrically connected the cathode of capacitance C4 and the positive input terminal of LED4 lamp groups；The anode of capacitance C4 is electrically connected respectively
Connect the cathode of the negative input end of LED3 lamp groups, the anode of capacitance C3, the cathode of rectifier diode D7 and rectifier diode D8；Capacitance
The cathode of C3 is electrically connected the anode of rectifier diode D6 and the positive input terminal of LED3 lamp groups.
Preferably, the driving transformer includes a transformer battery core；Be wound with the transformer battery core primary side around
The group vice-side winding identical with two structures；
Wherein, two vice-side windings are respectively first vice-side winding and second vice-side winding.
Preferably, the driving transformer includes identical the first transformer and the second transformer of structure；
The primary side winding of first transformer and the series connection of the primary side winding of second transformer.
Wherein, the vice-side winding of first transformer is first vice-side winding, the secondary of second transformer
Winding is second vice-side winding.
Preferably, the LED1 lamps group includes the LED of multiple series connection；The LED2 lamps group includes multiple series connection
LED。
Preferably, the LED3 lamps group includes the LED of multiple series connection；The LED4 lamps group includes multiple series connection
LED。
Preferably, the coiling direction of first inductor winding and second inductor winding is opposite.
Preferably, the primary side winding of the driving transformer is electrically connected with driving power；
Wherein, the driving power is AC power.
The beneficial effects of the utility model：The utility model compensate for the voltage difference of each LED light group using balance inductance, become
Two vice-side windings of depressor will export essentially equal electric current, and the electric current of so rectified rear each LED light group is also complete
It is equal, it is achieved thereby that between the LED light group of different voltages current balance purpose, this programme circuit structure is simple, without
Increase constant-current circuit, reduce production cost.
Brief description of the drawings
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, drawings in the following description are only
It is some embodiments of the utility model, for those of ordinary skill in the art, before not making the creative labor property
Put, other attached drawings can also be obtained according to these attached drawings.
Fig. 1 is the structure principle chart of the LED drive circuit of the prior art；
Fig. 2 is a kind of structure principle chart for multi-channel LED current equalization drive circuit that the utility model embodiment provides；
Fig. 3 is a kind of particular circuit configurations figure for multi-channel LED current equalization drive circuit that the utility model embodiment provides；
Fig. 4 is the structure principle chart for another multi-channel LED current equalization drive circuit that the utility model embodiment provides.
In figure：10th, driving power；20th, driving transformer；30th, balance inductance；41st, first via rectification circuit；42nd, second
Road rectification circuit.
Embodiment
Purpose of utility model, feature, advantage to enable the utility model is more obvious and understandable, below will knot
The attached drawing in the utility model embodiment is closed, the technical scheme in the utility model embodiment is clearly and completely described,
Obviously, the embodiments described below are only the utility model part of the embodiment, and not all embodiment.Based on this reality
With the embodiment in new, those of ordinary skill in the art are obtained all other without making creative work
Embodiment, shall fall within the protection scope of the present invention.
Further illustrate the technical solution of the utility model below with reference to the accompanying drawings and specific embodiments.
Please refer to Fig.2, a kind of multi-channel LED current equalization drive circuit provided by the utility model, including driving power 10, driving
Transformer 20, balance inductance 30 and two-way rectification circuit.Wherein, two-way rectification circuit is respectively first via rectification circuit 41 and
No. two rectification circuits 42.
Specifically, driving power 10 is AC power, the voltage output end of driving power 10 is electrically connected driving transformer 20
Primary side winding.
Driving transformer 20 includes first vice-side winding N1 and second vice-side winding N1 of the output phase with alternating voltage；As
A kind of optional embodiment, driving transformer 20 can be a change with the primary side winding vice-side winding identical with two structures
Depressor, is specially：
Driving transformer 20 includes a transformer battery core；A primary side winding and two structures are wound with the transformer battery core
Identical vice-side winding；
Wherein, two vice-side windings i.e. the first vice-side winding N1 and the second vice-side winding N2, the first vice-side winding N1 and second
The number of turn, phase, the coiling direction all same of vice-side winding N2.Please refer to Fig.2, the first vice-side winding N1 and the second vice-side winding N2
Same Name of Ends be respectively positioned on the upside of Fig. 2.
Specifically, balance inductance 30 includes inductance battery core, and two numbers of turn being wound in inductance battery core it is identical first
Inductor winding L1 and the second inductor winding L2；In the present embodiment, the coiling side of the first inductor winding L1 and the second inductor winding L2
To opposite.Please refer to Fig.2, the Same Name of Ends of the first inductor winding L1 is located on the left of Fig. 2, and the Same Name of Ends of the second inductor winding L2 is located at
On the right side of Fig. 2.
The specific electrical connection of each function module is as follows：
The Same Name of Ends of first vice-side winding N1 is electrically connected the Same Name of Ends of the first inductor winding L1；Second vice-side winding N2's is same
Name end is electrically connected the different name end of the second inductor winding L2；The different name end of first vice-side winding N1 and the different name of the first inductor winding L1
End is electrically connected two voltage input ends of first via rectification circuit 41；The different name end of second vice-side winding N2 and the second inductor winding L2
Same Name of Ends be electrically connected No. second rectification circuit 42 two voltage input ends.
It should be noted that in alternating current circuit, Same Name of Ends and different name end are for distinguishing electric potential direction, are definition
, certain nonspecific one end, interchangeable definition.
Please refer to Fig.2, by taking two paths of LED lamp group as an example, specific circuit conditioning principle is as described below：
The voltage for the LED light group that first via rectification circuit 41 drives is reduced to V1, the LED light of No. second rectification circuit 42 driving
The voltage of group is reduced to V2.
Assuming that V2 is more than V1, potential difference is △ V=V2-V1.
Assuming that the first vice-side winding N1, the second vice-side winding N2, the first inductor winding L1, the second inductor winding L2's is of the same name
Terminal voltage is just.
Because N1, N2 are identical, Vn1=Vn2；Because L1, L2 are identical, Vl1=Vl2, can be derived from,
Vn1=Vn2=V1+1/2 △ V, Vl1=Vl2=1/2 △ V.
It can be seen from the above that the drive circuit shown in Fig. 2 compensate for the voltage difference of each LED light group, two of driving transformer 20
Vice-side winding will export essentially equal electric current, after so rectified, the electric current of each LED light group be also it is essentially equal, from
And realize the purpose of the current balance of multiple LED light groups under different voltages.
Please continue to refer to Fig. 3, Fig. 3 is a kind of physical circuit knot of multi-channel LED current equalization drive circuit provided in this embodiment
Composition.
Specifically, the driving of first via rectification circuit 41 has LED1 lamps group and LED2 lamp groups；No. second rectification circuit 42 drives
There are LED3 lamps group and LED4 lamp groups.
First via rectification circuit 41 includes capacitance Cd1, rectifier diode D1, rectifier diode D2, rectifier diode D3, whole
Flow diode D4, capacitance C1 and capacitance C2.Physical circuit connection relation is as follows：
The different name end of first inductor winding L1 is electrically connected the cathode of capacitance Cd1, and the different name end of the first vice-side winding N1 is electrically connected
Connect the cathode of rectifier diode D2 and the anode of rectifier diode D4.Wherein, the cathode of capacitance Cd1 and rectifier diode D2 be just
Extremely two voltage input ends of first via rectification circuit 41.
The anode of capacitance Cd1 is electrically connected the cathode of rectifier diode D1 and the anode of rectifier diode D3；Rectification two
The anode of pole pipe D1 is electrically connected the cathode of capacitance C2 and the positive input terminal of LED2 lamp groups；The anode of capacitance C2 is electrically connected respectively
Connect the cathode of the negative input end of LED1 lamp groups, the anode of capacitance C1, the cathode of rectifier diode D3 and rectifier diode D4；Capacitance
The cathode of C1 is electrically connected the anode of rectifier diode D2 and the positive input terminal of LED1 lamp groups.
No. second rectification circuit 42 includes capacitance Cd2, rectifier diode D5, rectifier diode D6, rectifier diode D7, whole
Flow diode D8, capacitance C3 and capacitance C4.Physical circuit connection relation is as follows：
The Same Name of Ends of second inductor winding L2 is electrically connected the cathode of capacitance Cd2, and the different name end of the second vice-side winding N2 is electrically connected
Connect the cathode of rectifier diode D6 and the anode of rectifier diode D8；Wherein, the cathode of capacitance Cd2 and rectifier diode D6 be just
Extremely two voltage input ends of No. second rectification circuit 42.
The anode of capacitance Cd2 is electrically connected the cathode of rectifier diode D5 and the anode of rectifier diode D7；Rectification two
The anode of pole pipe D5 is electrically connected the cathode of capacitance C4 and the positive input terminal of LED4 lamp groups；The anode of capacitance C4 is electrically connected respectively
Connect the cathode of the negative input end of LED3 lamp groups, the anode of capacitance C3, the cathode of rectifier diode D7 and rectifier diode D8；Capacitance
The cathode of C3 is electrically connected the anode of rectifier diode D6 and the positive input terminal of LED3 lamp groups.
Specifically, LED1 lamp groups include the LED of multiple series connection；LED2 lamp groups include the LED of multiple series connection；LED3 lamps
Group includes the LED of multiple series connection；LED4 lamp groups include the LED of multiple series connection.
The present embodiment can realize the current balance of four paths of LEDs lamp groups, and need not increase constant-current circuit, according to specific experiment
Data show that for voltage difference in 10%-20%, the difference between current of the drive circuit of the present embodiment is only 1% between two paths of LED lamp group
Left and right, more perfectly realizes the current balance of each paths of LEDs lamp group.
Please continue to refer to Fig. 4, Fig. 4 is another multi-channel LED current equalization drive circuit that the utility model embodiment provides
Structure principle chart.
Driving transformer 20 can also use the identical transformer of two structures to realize.
Specifically, driving transformer 20 includes the first transformer and the second transformer；The primary side winding of first transformer and
The primary side winding series connection of second transformer.
Wherein, the vice-side winding of the first transformer is the first vice-side winding N1, and the vice-side winding of the second transformer is described
Second vice-side winding N2.
The present embodiment compensate for the voltage difference of each LED light group using balance inductance, and two vice-side windings of transformer will
Essentially equal electric current is exported, the electric current of so rectified rear each LED light group is also essentially equal, it is achieved thereby that different electricity
The purpose of current balance between the LED light group of pressure, this programme circuit structure is simple, without increasing constant-current circuit, reduces production
Cost.
The above, above example is only to illustrate the technical solution of the utility model, rather than its limitations；Although ginseng
The utility model is described in detail according to previous embodiment, it will be understood by those of ordinary skill in the art that：It is still
It can modify to the technical solution described in foregoing embodiments, or which part technical characteristic is equally replaced
Change；And these modifications or replacement, the essence of appropriate technical solution is departed from various embodiments of the utility model technical solution
Spirit and scope.
Claims (9)
1. a kind of multi-channel LED current equalization drive circuit, it is characterised in that including driving transformer, balance inductance and two-way rectified current
Road；
The driving transformer includes first vice-side winding and second vice-side winding of the output phase with alternating voltage；The balance electricity
Sense includes inductance battery core, and identical the first inductor winding of two numbers of turn being wound in the inductance battery core and the second inductance around
Group；
The Same Name of Ends of first vice-side winding is electrically connected the Same Name of Ends of first inductor winding；Second vice-side winding
Same Name of Ends is electrically connected the different name end of second inductor winding；
The different name end of first vice-side winding and the different name end of first inductor winding are electrically connected first via rectification circuit
Two voltage input ends；It is whole that the Same Name of Ends of the different name end of second vice-side winding and second inductor winding is electrically connected the second tunnel
Two voltage input ends of current circuit.
2. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that the first via rectification circuit drives
It is dynamic to have LED1 lamps group and LED2 lamp groups；
The first via rectification circuit includes capacitance Cd1, rectifier diode D1, rectifier diode D2, rectifier diode D3, rectification
Diode D4, capacitance C1 and capacitance C2；
The different name end of first inductor winding is electrically connected the cathode of capacitance Cd1, and the different name end of first vice-side winding is electrically connected
Connect the cathode of rectifier diode D2 and the anode of rectifier diode D4；
The anode of capacitance Cd1 is electrically connected the cathode of rectifier diode D1 and the anode of rectifier diode D3；Rectifier diode
The anode of D1 is electrically connected the cathode of capacitance C2 and the positive input terminal of LED2 lamp groups；The anode of capacitance C2 is electrically connected
The negative input end of LED1 lamp groups, the anode of capacitance C1, the cathode of the cathode of rectifier diode D3 and rectifier diode D4；Capacitance C1
Cathode be electrically connected the anode of rectifier diode D2 and the positive input terminal of LED1 lamp groups.
3. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that No. second rectification circuit drives
It is dynamic to have LED3 lamps group and LED4 lamp groups；
No. second rectification circuit includes capacitance Cd2, rectifier diode D5, rectifier diode D6, rectifier diode D7, rectification
Diode D8, capacitance C3 and capacitance C4；
The Same Name of Ends of second inductor winding is electrically connected the cathode of capacitance Cd2, and the different name end of second vice-side winding is electrically connected
Connect the cathode of rectifier diode D6 and the anode of rectifier diode D8；
The anode of capacitance Cd2 is electrically connected the cathode of rectifier diode D5 and the anode of rectifier diode D7；Rectifier diode
The anode of D5 is electrically connected the cathode of capacitance C4 and the positive input terminal of LED4 lamp groups；The anode of capacitance C4 is electrically connected
The negative input end of LED3 lamp groups, the anode of capacitance C3, the cathode of the cathode of rectifier diode D7 and rectifier diode D8；Capacitance C3
Cathode be electrically connected the anode of rectifier diode D6 and the positive input terminal of LED3 lamp groups.
4. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that the driving transformer includes one
Transformer battery core；The primary side winding vice-side winding identical with two structures is wound with the transformer battery core；
Wherein, two vice-side windings are respectively first vice-side winding and second vice-side winding.
5. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that the driving transformer includes knot
Structure identical the first transformer and the second transformer；
The primary side winding of first transformer and the series connection of the primary side winding of second transformer；
Wherein, the vice-side winding of first transformer is first vice-side winding, the vice-side winding of second transformer
For second vice-side winding.
6. multi-channel LED current equalization drive circuit according to claim 2, it is characterised in that the LED1 lamps group includes more
The LED of a series connection；The LED2 lamps group includes the LED of multiple series connection.
7. multi-channel LED current equalization drive circuit according to claim 3, it is characterised in that the LED3 lamps group includes more
The LED of a series connection；The LED4 lamps group includes the LED of multiple series connection.
8. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that first inductor winding and institute
The coiling direction for stating the second inductor winding is opposite.
9. multi-channel LED current equalization drive circuit according to claim 1, it is characterised in that the primary side of the driving transformer
Winding is electrically connected with driving power；
Wherein, the driving power is AC power.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720887260.4U CN207266333U (en) | 2017-07-20 | 2017-07-20 | A kind of multi-channel LED current equalization drive circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720887260.4U CN207266333U (en) | 2017-07-20 | 2017-07-20 | A kind of multi-channel LED current equalization drive circuit |
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| CN207266333U true CN207266333U (en) | 2018-04-20 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107155244A (en) * | 2017-07-20 | 2017-09-12 | 东莞市紫能电子科技有限公司 | A kind of multi-channel LED current equalization drive circuit |
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- 2017-07-20 CN CN201720887260.4U patent/CN207266333U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107155244A (en) * | 2017-07-20 | 2017-09-12 | 东莞市紫能电子科技有限公司 | A kind of multi-channel LED current equalization drive circuit |
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