CN209731658U

CN209731658U - LED drive circuit

Info

Publication number: CN209731658U
Application number: CN201920170690.3U
Authority: CN
Inventors: 刘志峰
Original assignee: Shenzhen Lujing Sunshine Electricity Co Ltd
Current assignee: Shenzhen Lujing Sunshine Electricity Co Ltd
Priority date: 2019-01-29
Filing date: 2019-01-29
Publication date: 2019-12-03
Anticipated expiration: 2029-01-29

Abstract

The utility model discloses a kind of LED drive circuit, comprising: LED drive control module, current detection module, transformer and LED load module；The input terminal of LED drive control module is connect with power supply and current detection module respectively, and the output end of LED drive control module and the input terminal of transformer connect；The output end of transformer is connect with LED load module；LED drive control module includes the switch submodule of LED drive control integrated circuit and several power switch tube compositions parallel with one another, and LED drive control integrated circuit is connect with current detection module and switch submodule respectively；Switch submodule is also connect with the primary side of transformer respectively.The utility model transformer output end is directly connected to LED load, cancels output rectifier and filter, and circuit stability is high, it reduces by available circuit 1/3 number of electronic components, greatly reduction small product size, reduces production cost, circuit efficiency is improved, realizes the high efficiency drive function of LED drive circuit.

Description

LED drive circuit

Technical field

The utility model relates to LED drive power technical field more particularly to a kind of LED drive circuits.

Background technique

Under the background that global energy shortage, environmental consciousness are continuously improved, the LED (light emitting diode) of green energy conservation is illuminated It is developing rapidly.Therefore, LED drive circuit requirement is also being continuously improved, high reliability, high efficiency, Gao Hengliu Precision, low system cost, small circuit size and security isolation etc. become the key technique index of LED drive circuit.For reality The security isolation of existing LED drive circuit, existing LED drive circuit none do not use the normal output rectification filter technology of power supply Scheme ensures that LED drive circuit is safely isolated, and adds output rectification filter in LED drive circuit, certainly will need in electricity Increase electronic component in road, small product size is caused to increase, also increases production cost；On the other hand, existing LED driving electricity Road work generates biggish electric current, and output power of circuit is big, causes circuit efficiency low.

Therefore, the prior art is defective, needs to improve.

Utility model content

The purpose of the utility model is to overcome the deficiencies in the prior art, provide a kind of LED drive circuit.

The technical solution of the utility model is as follows: a kind of LED drive circuit, comprising: LED drive control module, electric current inspection Survey module, transformer and LED load module；The input terminal of the LED drive control module respectively with power supply and current detecting Module connection, the output end of the LED drive control module are connect with the input terminal of the transformer；The output of the transformer End is connect with the LED load module as load；If the LED drive control module include LED drive control integrated circuit and Do the switch submodule of power switch tube composition parallel with one another, the LED drive control integrated circuit respectively with current detecting Module is connected with switch submodule；The switch submodule is also connect with the primary side of the transformer respectively.

Further, the LED drive control integrated circuit includes drive control chip；The drive control chip packet It includes:

Current detecting foot is connect with the current detection module, for detecting the output voltage of LED drive circuit and defeated Electric current out；

Switching tube drives output pin, connect respectively with first power switch tube and the second power switch tube, for controlling Make the on or off of first power switch tube and the second power switch tube.

Further, the primary side of the transformer includes primary coil and ancillary coil；One end of the primary coil with The other end of first inductance connection, the primary coil is connect with first capacitor；One end of the ancillary coil and the one or two pole Pipe connection.

Further, the transformer further includes secondary side；The secondary side of the transformer includes the first secondary coil and second Secondary coil, first secondary coil and second subprime coil are connect with the LED load module respectively.

Further, the current detection module includes the first current detection circuit and the second current detection circuit；It is described The output end of first current detection circuit is connect with the first sample resistance, and the output end of first current detection circuit connects institute State the input terminal of LED drive control integrated circuit；The input terminal of second current detection circuit is connected to the second sample resistance Between third sample resistance, the output end of second current detection circuit connects the LED drive control integrated circuit Input terminal.

Further, the LED load module includes the LED load electricity to match with several power switch tube quantity Road.

Using the above scheme, the utility model has the following beneficial effects:

Two kinds of working conditions of the utility model form complete circuit operation principle, and LED drive control integrated circuit is certainly The electric current and voltage of dynamic acquisition current detection module, and analytical calculation is carried out according to the collected data, control the first power tube With the on or off of the second power tube, the driving function of LED drive circuit is realized, transformer output end is directly and LED load Connection, circuit efficiency are high.

The utility model compared with the prior art for, eliminate output rectifier and filter, transformer output end is direct LED load is connected, circuit stability is high, reduces in available circuit 1/3 number of electronic components, greatly reduction product body Product reduces production cost, improves circuit efficiency, realize the high efficiency drive function of LED drive circuit.

Detailed description of the invention

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, the accompanying drawings in the following description is only It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor Under, the structure that can also be shown according to these attached drawings obtains other attached drawings.

Fig. 1 is the block diagram of the utility model LED drive circuit；

Fig. 2 is the schematic diagram of the utility model LED drive circuit.

The embodiments will be further described with reference to the accompanying drawings for the realization, functional characteristics and advantage of the utility model aim.

Specific embodiment

Below in conjunction with the drawings and specific embodiments, the utility model is described in detail.

Shown in referring to Figures 1 and 2, the utility model provides a kind of LED drive circuit, comprising: LED drive control module 1, Current detection module 2, transformer 3 and LED load module 4；The input terminal of the LED drive control module 1 respectively with power supply It is connected with current detection module 2, the output end of the LED drive control module 1 is connect with the input terminal of the transformer 3；Institute The output end for stating transformer 3 is connect with the LED load module 4 as load；The LED drive control module 1 drives including LED Control the switch submodule 12 of integrated circuit 11 and several power switch tube compositions parallel with one another, the LED drive control collection 12 are connect with current detection module 2 and switch submodule respectively at circuit 11；The switch submodule 12 also respectively with the change The primary side of depressor 3 connects.

As one of embodiment, the switch submodule 12 is by the first power switch tube Q1 parallel with one another and second Power switch tube Q2 composition, the first power switch tube Q1 and the second power switch tube Q2 can be metal-oxide-semiconductor.

In the present embodiment, the detected value of current detection module described in the LED drive control integrated circuit automatic collection, And analytical calculation is carried out according to the collected data, the level height that LED drive control integrated circuit is exported according to calculated value control. When LED drive control integrated circuit exports high level, the first power switch tube Q1 conducting, the second power switch tube Q2 cut-off； When LED drive control integrated circuit exports low level, the first power switch tube Q1 cut-off, the second power switch tube Q2 conducting.

As one embodiment, the LED drive control integrated circuit 11 includes drive control chip, the drive control Chip includes:

Current detecting foot is connect with the current detection module 2, for detect LED drive circuit output voltage and Export electric current；

Switching tube drives output pin, connect respectively with the first power switch tube Q1 and the second power switch tube Q2, uses In the on or off for controlling the first power switch tube Q1 and the second power switch tube Q2.

As one embodiment, the current detection module 2 includes the first current detection circuit 21 and the second current detecting Circuit 22；The output end of first current detection circuit 21 is connect with the first sample resistance RS, the first current detecting electricity The output end on road 21 connects the input terminal of the LED drive control integrated circuit 11；Second current detection circuit 22 it is defeated Enter end to be connected between the second sample resistance RV1 and third sample resistance RV2, the output end of second current detection circuit 22 Connect the input terminal of the LED drive control integrated circuit 11.

As one embodiment, the primary side of the transformer 3 includes primary coil and ancillary coil；The primary coil One end and the first inductance connection, the other end of the primary coil are connect with first capacitor；One end of the ancillary coil and the The connection of one diode.

In the present embodiment, the transformer 3 further includes secondary side；The secondary side of the transformer 3 includes the first secondary coil With second subprime coil, the secondary side of the transformer 3 includes the first secondary coil and second subprime coil, first secondary wire Circle and second subprime coil are connect with the LED load module 4 respectively.

As one embodiment, the LED load module includes the LED to match with several power switch tube quantity Load circuit, several LED load circuits are in series by several LED light.

In the present embodiment, the LED load module 4 includes the first LED load circuit 41 and the second LED load circuit 42, first LED load circuit 41 and the second LED load circuit 42 are connect with the output end on the secondary side of transformer 3 respectively.

Referring to shown in Fig. 2, utility model works principle is as follows:

When positive pole V+ is powered, LED drive control integrated circuit 11 controls the first power switch tube Q1 and is connected, and second Power switch tube Q2 cut-off, the voltage in circuit is transmitted to the primary coil of 3 primary side of transformer, first through the first inductance LS at this time Capacitor Cr and the first sample resistance RS return to power cathode V-；Positive voltage on the pin 1 of 3 primary coil of transformer, which flows to, to be drawn Foot 2,6 positive voltage of the pin output of secondary the first secondary coil of side of corresponding transformer 3, positive voltage is from the first LED load circuit 41 Voltage input end LD+ flow to load end LD-；And the output electric current of LED drive circuit generates electric current by the first sample resistance RS Sampling voltage, and detected by the first current detection circuit 21, according to the detected value of the first current detection circuit 21 adjustment first The resistance value of sample resistance RS realizes the output of control LED drive circuit to change the primary coil partial pressure of 3 primary side of transformer The size of electric current；On the other hand, positive voltage flows to pin 7 on the pin 8 of 3 ancillary coil of transformer, 3 ancillary coil of transformer The output of 7 positive voltage of pin flows through the second sample resistance RV1 and generates electric current, and detected by the second current detection circuit 22, passes through The detected value of second current detection circuit 22 calculates separately out the partial pressure value of the second sample resistance RV1 and third sample resistance RV2, Adjust the high voltage or low electricity of the resistance value control LED drive circuit output of the second sample resistance RV1 and third sample resistance RV2 Pressure.

Under another working condition, LED drive control integrated circuit 11, which controls the first power switch tube Q1, to be ended, and second The voltage of power switch tube Q2 conducting, circuit turns to, and positive voltage flows through pin 1, first by the pin 2 of 3 primary coil of transformer Inductance LS to the second power switch tube Q2,3 positive voltage of the pin output of corresponding 3 secondary side second subprime coil of transformer, positive voltage Load end LD- is flowed to from the voltage input end LD+ of the second LED load circuit 42；And under this working condition, LED drive circuit Output electric current current sampling voltage is equally generated by the first sample resistance RS, and detected by the first current detection circuit 21, The resistance value that the first sample resistance RS is adjusted according to the detected value of the first current detection circuit 21, to change 3 primary side of transformer Primary coil partial pressure realizes the size of the output electric current of control LED drive circuit；On the other hand, transformer 3 ancillary coil draws Positive voltage flows to pin 7 on foot 8, and 7 positive voltage of the pin output of 3 ancillary coil of transformer flows through the second sample resistance RV1 generation Electric current, and detected by the second current detection circuit 22, is calculated separately out by the detected value of the second current detection circuit 22 The partial pressure value of two sample resistance RV1 and third sample resistance RV2, adjustment the second sample resistance RV1's and third sample resistance RV2 Resistance value controls the high voltage or low-voltage of LED drive circuit output.

Compared with prior art, the utility model has the following beneficial effects:

The above is only the preferred embodiments of the present utility model only, is not intended to limit the utility model, all practical at this Made any modifications, equivalent replacements, and improvements etc., should be included in the guarantor of the utility model within novel spirit and principle Within the scope of shield.

Claims

1. a kind of LED drive circuit characterized by comprising LED drive control module, current detection module, transformer and LED load module；The input terminal of the LED drive control module is connect with power supply and current detection module respectively, and the LED drives The output end of dynamic control module is connect with the input terminal of the transformer；The output end of the transformer and the LED as load Load blocks connection；The LED drive control module includes that LED drive control integrated circuit and several power parallel with one another are opened The switch submodule of pipe composition is closed, the LED drive control integrated circuit connects with current detection module and switch submodule respectively It connects；The switch submodule is also connect with the primary side of the transformer respectively.

2. LED drive circuit according to claim 1, which is characterized in that the LED drive control integrated circuit includes driving Dynamic control chip.

3. LED drive circuit according to claim 1, which is characterized in that the primary side of the transformer includes primary coil And ancillary coil；One end of the primary coil and the first inductance connection, the other end and first capacitor of the primary coil connect It connects；One end of the ancillary coil is connect with first diode.

4. LED drive circuit according to claim 3, which is characterized in that the transformer further includes secondary side；The transformation The secondary side of device includes the first secondary coil and second subprime coil, first secondary coil and second subprime coil respectively with institute State the connection of LED load module.

5. LED drive circuit according to claim 1, which is characterized in that the current detection module includes the first electric current Detection circuit and the second current detection circuit；The output end of first current detection circuit is connect with the first sample resistance, institute The output end for stating the first current detection circuit connects the input terminal of the LED drive control integrated circuit；The second electric current inspection The input terminal of slowdown monitoring circuit is connected between the second sample resistance and third sample resistance, the output of second current detection circuit End connects the input terminal of the LED drive control integrated circuit.

6. LED drive circuit according to claim 1, which is characterized in that the LED load module include with it is described several The LED load circuit that power switch tube quantity matches.