Full-color LED display screen driving circuit

Abstract

The utility model discloses a full-color LED display screen driving circuit which comprises a display controller, a row control module and at least two display driving units. The display controller is connected with each display driving unit through the row control module, and the red light driving end of each red light display branch of each display driving unit is connected with different red light constant current ports of the constant current driving chip of the display driving unit. The green light driving end of each green light display branch of each display driving unit is respectively connected with different green light constant current ports of the constant current driving chip of the display driving unit; and the blue light driving ends of the blue light display branches of each display driving unit are respectively connected with different blue light constant current ports of the constant current driving chip of the display driving unit. According to the full-color LED display screen, the problem of non-uniform display caused by local overheating of the full-color LED display screen can be effectively avoided.

Description

Technical Field

[0001] The utility model relates to the field of LED displays, in particular to a full-color LED display driving circuit. Background Art

[0002] For the existing full-color LED displays, the red LED beads, green LED beads and blue LED beads are respectively driven by different constant-current driving chips; under the same working conditions, the forward conduction voltage drops of the red LED beads, green LED beads and blue LED beads are different. The forward conduction voltage drop of the red LED beads is the smallest, and the conduction current of the red LED beads is usually higher than that of the blue and green LED beads. This causes the constant-current driving chip for driving the red LED beads to bear more additional voltage drops, and the constant-current driving chip for driving the red LED beads is prone to overheating during operation, resulting in local overheating problems in the full-color LED display, making the full-color LED display prone to problems of uneven display colors and reducing the display effect of the full-color LED display.

[0003] In view of the existence of the above problems, it is necessary to study a full-color LED display driving circuit to overcome the deficiencies in the prior art. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a full-color LED display driving circuit to overcome the deficiencies in the prior art.

[0005] To achieve the above object, the solution of the utility model is:

[0006] A full-color LED display driving circuit, which includes a display controller, a row control module, and at least two display driving units; the row control module includes a plurality of switching tubes, the input ends of each switching tube are connected to a driving power supply, and the control ends of each switching tube are respectively connected to the display controller; the display driving unit includes at least one red light display branch, at least one green light display branch, at least one blue light display branch, and a constant current driving chip; each red light display branch includes a plurality of red light LED beads, the anodes of the red light LED beads of each red light display branch are respectively connected to the output ends of the switching tubes of the row control module, and the cathodes of the red light LED beads of each red light display branch are connected to the red light driving end of the red light display branch; each green light display branch includes a plurality of green light LED beads, the anodes of the green light LED beads of each green light display branch are respectively connected to the output ends of the switching tubes of the row control module, and the cathodes of the green light LED beads of each green light display branch are connected to the green light driving end of the green light display branch; each blue light display branch includes a plurality of blue light LED beads, the anodes of the blue light LED beads of each blue light display branch are respectively connected to the output ends of the switching tubes of the row control module, and the cathodes of the blue light LED beads of each blue light display branch are connected to the blue light driving end of the blue light display branch; the constant current driving chip is connected to the display controller, and the constant current driving chip has at least one red light constant current port, at least one green light constant current port, and at least one blue light constant current port; the red light driving ends of the red light display branches of each display driving unit are respectively connected to different red light constant current ports of the constant current driving chip of the display driving unit, the green light driving ends of the green light display branches of each display driving unit are respectively connected to different green light constant current ports of the constant current driving chip of the display driving unit, and the blue light driving ends of the blue light display branches of each display driving unit are respectively connected to different blue light constant current ports of the constant current driving chip of the display driving unit.

[0007] The constant current driving chip is internally provided with a main control module, a communication module, a display processing module, a video memory module, a first constant current control module, a second constant current control module, and a third constant current control module; the main control module is respectively connected to the communication module, the display processing module, and the video memory module, and the communication module is used for communicating with the display controller; the first constant current control module, the second constant current control module, and the third constant current control module are respectively connected to the display processing module, the first constant current control module is connected with a first current setting resistor, the first constant current control module leads out each red light constant current port of the constant current driving chip, the second constant current control module is connected with a second current setting resistor, the second constant current control module leads out each green light constant current port of the constant current driving chip, the third constant current control module is connected with a third current setting resistor, and the third constant current control module leads out each blue light constant current port of the constant current driving chip.

[0008] The first constant current control module of the constant current driving chip leads out each red light constant current port of the constant current driving chip through the first blanking module. The second constant current control module of the constant current driving chip leads out each green light constant current port of the constant current driving chip through the second blanking module. The third constant current control module of the constant current driving chip leads out each blue light constant current port of the constant current driving chip through the third blanking module. The main control module is connected to the first blanking module, the second blanking module and the third blanking module through the blanking control module.

[0009] The communication module of the constant current driving chip leads out the data input port, data output port, latch port, clock port and enable port of the constant current driving chip. The latch port, clock port and enable port of the constant current driving chip of each display driving unit are respectively connected to the display controller. The data input port of the constant current driving chip of the first display driving unit in each display driving unit is connected to the display controller. The data output port of the constant current driving chip of the first display driving unit in each display driving unit is connected to the data input port of the constant current driving chip of the second display driving unit, and so on until the data output port of the constant current driving chip of the penultimate display driving unit is connected to the data input port of the constant current driving chip of the last display driving unit.

[0010] The switching tube uses a MOS tube.

[0011] After adopting the above scheme, the red light display branches, blue light display branches and green light display branches of each display driving unit of the present utility model all provide current through a constant current driving chip of the display driving unit. In this way, the power consumption of the constant current driving chips of each display driving unit is similar, and the heat generation of the constant current driving chips of each display driving unit is the same, thus avoiding the phenomenon that some constant current driving chips in the existing full-color display screen are prone to overheating during operation, and solving the problem of uneven display colors in the full-color LED display screen caused by local overheating. Description of the Drawings

[0012] Figure 1 is the circuit schematic diagram of the present utility model.

[0013] Figure 2 is the principle block diagram of the constant current driving chip of the present utility model.

[0014] Label Description:

[0015] Display controller 1,

[0016] Row control module 2, switching tube K,

[0017] Display driving unit 3,

[0018] Red light display branch 31, red light LED lamp bead DR,

[0019] Green light display branch 32, green light LED lamp bead DG,

[0020] Blue light display branch 33, blue light LED lamp bead DB,

[0021] Constant current drive chip 34,

[0022] Main control module 341,

[0023] Communication module 342,

[0024] Display processing module 343,

[0025] Video memory module 344,

[0026] First constant current control module 345, first blanking module 3451, first current setting resistor 3452,

[0027] Second constant current control module 346, second blanking module 3461, second current setting resistor 3462,

[0028] Third constant current control module 347, third blanking module 3471, third current setting resistor 3472,

[0029] Blanking control module 348,

[0030] Red light constant current port Rout, green light constant current port Gout, blue light constant current port Bout,

[0031] Data input port SDI, data output port SDO, latch port LATCH, clock port SCLK, enable port OE,

[0032] Drive power supply 4. Detailed implementation manners

[0033] In order to further explain the technical solution of the present invention, the present invention will be elaborated in detail below through specific embodiments.

[0034] Such as Figure 1 And Figure 2As shown in the figure, the present utility model discloses a full-color LED display driving circuit, which includes a display controller 1, a row control module 2, and at least two display driving units 3; the row control module 2 includes a plurality of switching tubes K, the input ends of each switching tube K are connected to a driving power supply 4, and the control ends of each switching tube K are respectively connected to the display controller 1; the display driving unit 3 includes at least one red light display branch 31, at least one green light display branch 32, at least one blue light display branch 33 and a constant current driving chip 34; each red light display branch 31 includes a plurality of red light LED beads DR, the anodes of the red light LED beads DR in each red light display branch 31 are respectively connected to the output ends of the switching tubes K of the row control module 2, and the cathodes of the red light LED beads DR in each red light display branch 31 are connected to the red light driving end of this red light display branch 31; each green light display branch 32 includes a plurality of green light LED beads 321, the anodes of the green light LED beads 321 in each green light display branch 32 are respectively connected to the output ends of the switching tubes K of the row control module 2, and the cathodes of the green light LED beads 321 in each green light display branch 32 are connected to the green light driving end of this green light display branch 32; each blue light display branch 33 includes a plurality of blue light LED beads DB, the anodes of the blue light LED beads DB in each blue light display branch 33 are respectively connected to the output ends of the switching tubes K of the row control module 2, and the cathodes of the blue light LED beads DB in each blue light display branch 33 are connected to the blue light driving end of this blue light display branch 33; the constant current driving chip 34 is connected to the display controller 1, and the constant current driving chip 34 has at least one red light constant current port Rout, at least one green light constant current port Gout and at least one blue light constant current port Bout; the red light driving ends of the red light display branches 31 of each display driving unit 3 are respectively connected to different red light constant current ports Rout of the constant current driving chip 34 of this display driving unit 3, the green light driving ends of the green light display branches 32 of each display driving unit 3 are respectively connected to different green light constant current ports Gout of the constant current driving chip 34 of this display driving unit 3, and the blue light driving ends of the blue light display branches 33 of each display driving unit 3 are respectively connected to different blue light constant current ports Bout of the constant current driving chip 34 of this display driving unit 3.

[0035] In the present utility model, each red light display branch 31, each blue light display branch 33, and each green light display branch 32 of each display driving unit 3 of the present utility model are all supplied with current by a constant current driving chip 34 of the display driving unit 3. In this way, the power consumption of the constant current driving chips 34 of each display driving unit 3 is similar, so that the heat generation of the constant current driving chips 34 of each display driving unit 3 is the same, thereby avoiding the phenomenon that some of the constant current driving chips 34 in the existing full-color display screen are prone to overheating during operation, and solving the problem that the existing full-color LED display screen has uneven display colors due to local overheating.

[0036] In an embodiment of the present utility model, the constant current driving chip 34 is internally provided with a main control module 341, a communication module 342, a display processing module 343, a video memory module 344, a first constant current control module 345, a second constant current control module 346, and a third constant current control module 347. The main control module 341 is respectively connected to the communication module 342, the display processing module 343, and the video memory module 344. The communication module 342 is used for communicating with the display controller 1. The first constant current control module 345, the second constant current control module 346, and the third constant current control module 347 are respectively connected to the display processing module 343. The first constant current control module 345 is connected with a first current setting resistor 3452. The first constant current control module 345 leads out each red light constant current port Rout of the constant current driving chip 34. The second constant current control module 346 is connected with a second current setting resistor 3462. The second constant current control module 346 leads out each green light constant current port Gout of the constant current driving chip 34. The third constant current control module 347 is connected with a third current setting resistor 3472. The third constant current control module 347 leads out each blue light constant current port Bout of the constant current driving chip 34. Among them, the first current setting resistor 3452 is used for setting the output current of each red light constant current port Rout. The second current setting resistor 3462 is used for setting the output current of each green light constant current port Gout. The third current setting resistor 3472 is used for setting the output current of each blue light constant current port Bout. The first current setting resistor 3452, the second current setting resistor 3462, and the third current setting resistor 3472 can be built into the constant current driving chip 34 or can be arranged outside the constant current driving chip 34. In addition, in the present utility model, each red light constant current port Rout of the constant current driving chip 34 is led out by the first constant current control module 345, each green light constant current port Gout of the constant current driving chip 34 is led out by the second constant current control module 346, and each blue light constant current port Bout of the constant current driving chip 34 is led out by the third constant current control module 347. The first constant current control module 345, the second constant current control module 346, and the third constant current control module 347 are independent of each other, so as to avoid the problem of mutual interference among the red light constant current port Rout, the green light constant current port Gout, and the blue light constant current port Bout.

[0037] In an embodiment of the present utility model, the first constant current control module 345 leads out each red constant current port Rout of the constant current driving chip 34 through the first blanking module 3451, the second constant current control module 346 leads out each green constant current port Gout of the constant current driving chip 34 through the second blanking module 3461, and the third constant current control module 347 leads out each blue constant current port Bout of the constant current driving chip 34 through the third blanking module 3471; the main control module 341 controls the first blanking module 3451, the second blanking module 3461, and the third blanking module 3471 by connecting to the first blanking module 3451, the second blanking module 3461, and the third blanking module 3471 through the blanking control module 8. The first blanking module 3451, the second blanking module 3461, and the third blanking module 3471 are used to prevent the "ghosting" problem of the full-color LED display screen. The first blanking module 3451, the second blanking module 3461, the third blanking module 3471, and the blanking control module 8 are common circuits.

[0038] In an embodiment of the present utility model, the communication module 342 of the constant current driving chip 34 communicates with the display controller 1 through the SDI protocol. The communication module 342 of the constant current driving chip 34 leads out the data input port SDI, the data output port SDO, the latch port LATCH, the clock port SCLK, and the enable port OE of the constant current driving chip 34; the latch port LATCH, the clock port SCLK, and the enable port OE of the constant current driving chip 34 of each display driving unit 3 are respectively connected to the display controller 1; the data input port SDI of the constant current driving chip 34 of the first display driving unit 3 in each display driving unit 3 is connected to the display controller 1; the data output port SDO of the constant current driving chip 34 of the first display driving unit 3 in each display driving unit 3 is connected to the data input port SDI of the constant current driving chip 34 of the second display driving unit 3, and so on until the data output port SDO of the constant current driving chip 34 of the penultimate display driving unit 3 is connected to the data input port SDI of the constant current driving chip 34 of the last display driving unit 3.

[0039] In an embodiment of the present utility model, the switching tube K is a MOS tube, and the MOS tube has the advantage of fast response speed.

[0040] The above embodiments and diagrams do not limit the product form and style of the present utility model. Any appropriate changes or modifications made by those of ordinary skill in the art shall be regarded as not departing from the patent scope of the present utility model.

Claims

1. A full-color LED display screen driving circuit, characterized in that: It includes a display controller, a row control module, and at least two display driving units; The row control module includes a plurality of switch tubes, the input end of each switch tube is connected to a driving power supply, and the control end of each switch tube is respectively connected to a display controller; The display driving unit comprises at least one red light display branch, at least one green light display branch, at least one blue light display branch and a constant current driving chip; Each red light display branch includes a plurality of red light LED lamp beads, the anodes of each red light LED lamp beads of each red light display branch are respectively connected to the output ends of each switch tube of the row control module, and the cathodes of each red light LED lamp beads of each red light display branch are connected to the red light driving end of the red light display branch; Each green light display branch includes a plurality of green light LED lamp beads, the anodes of each green light LED lamp beads of each green light display branch are respectively connected to the output ends of each switch tube of the row control module, and the cathodes of each green light LED lamp beads of each green light display branch are connected to the green light driving end of the green light display branch; Each blue light display branch includes a plurality of blue light LED lamp beads, the anodes of each blue light LED lamp beads of each blue light display branch are respectively connected to the output ends of each switch tube of the row control module, and the cathodes of each blue light LED lamp beads of each blue light display branch are connected to the blue light driving end of the blue light display branch; The constant current driving chip is connected to the display controller, and the constant current driving chip has at least one red light constant current port, at least one green light constant current port and at least one blue light constant current port; The red light driving ends of each red light display branch of each display driving unit are respectively connected to different red light constant current ports of the constant current driving chip of the display driving unit, the green light driving ends of each green light display branch of each display driving unit are respectively connected to different green light constant current ports of the constant current driving chip of the display driving unit, and the blue light driving ends of each blue light display branch of each display driving unit are respectively connected to different blue light constant current ports of the constant current driving chip of the display driving unit.

2. A full-color LED display screen driving circuit as claimed in claim 1, characterized in that: The constant current drive chip is built with a main control module, a communication module, a display processing module, a display memory module, a first constant current control module, a second constant current control module and a third constant current control module; The main control module is respectively connected to the communication module, the display processing module and the display memory module, and the communication module is used to communicate with the display controller; The first constant current control module, the second constant current control module and the third constant current control module are respectively connected to the display processing module, the first constant current control module is connected to the first current setting resistor, the first constant current control module leads to each red light constant current port of the constant current driving chip, the second constant current control module is connected to the second current setting resistor, the second constant current control module leads to each green light constant current port of the constant current driving chip, the third constant current control module is connected to the third current setting resistor, and the third constant current control module leads to each blue light constant current port of the constant current driving chip.

3. A full-color LED display screen driving circuit as claimed in claim 2, characterized in that: The first constant current control module of the constant current drive chip leads to each red light constant current port of the constant current drive chip through the first blanking module, the second constant current control module of the constant current drive chip leads to each green light constant current port of the constant current drive chip through the second blanking module, and the third constant current control module of the constant current drive chip leads to each blue light constant current port of the constant current drive chip through the third blanking module; The main control module is connected to the first blanking module, the second blanking module and the third blanking module through the blanking control module.

4. A full-color LED display screen driving circuit as claimed in claim 2, characterized in that: The communication module of the constant current drive chip leads to the data input port, data output port, latch port, clock port and enable port of the constant current drive chip. The latch port, clock port and enable port of the constant current driving chip of each display driving unit are respectively connected to the display controller; the data input port of the constant current driving chip of the first display driving unit in each display driving unit is connected to the display controller; The data output port of the constant current driving chip of the first display driving unit in each display driving unit is connected to the data input port of the constant current driving chip of the second display driving unit, and so on, until the data output port of the constant current driving chip of the second to last display driving unit is connected to the data input port of the constant current driving chip of the first to last display driving unit.

5. A full-color LED display screen driving circuit as claimed in claim 1, characterized in that: The switch tube is a MOS tube.

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