What is the Refresh Rate and Gray Level of LED Display

What does LED display refresh rate and gray level mean? As follow optokingdom Engineer will explain for everyone.

With the development of indoor LED display and application more and more, both in the command center, the monitoring center and the studio, you can see the LED display is widely used. However, the overall performance of the LED display system, the display is able to meet the needs of the users? Whether these LED display images can accord with human visual viewing? These LED display can withstand different camera angles of different camera shutter test? This is the LED display needs to face the need to consider the problem, I would some factors affecting LED display (including the refresh and gray level etc.) make a analysis.
LED display refresh rate (visual refresh rate)

“Visual refresh rate” refers to the rate of screen updates, usually in Hertz (Hz) as a unit, in general, the visual refresh rate of more than 3000Hz, for high-performance LED display. The higher the visual refresh frequency, the more stable the screen display, the smaller the sense of visual flicker. LED display low “visual refresh rate”, in addition to its influence on camera, photography, horizontal horizontal stripes, but also has a similar lighting and flashing tens of thousands of pieces of image, the human eye watch may therefore produce discomfort, and even cause damage to the eyes.

Although the human eye, the visual refresh rate of more than 60Hz has been felt is a continuous picture, but the higher the visual refresh frequency, the more stable the image display, the more difficult to feel the human eye fatigue. Now in the high quality video, in order to get a more detailed picture, such as wonderful playback or close-up photography process, have to take more than 1000Hz per second camera. At this time, LED display for will be captured, under the high-speed shutter can still show footage (no black scan line) or continuous tone, is a great challenge.

Gray level of LED display screen

“Gray level” refers to a variety of colors in between the dark and the light, the color changes with different class, generally in the 14 bit gray scale (bit), which has at least more than 16384 kinds of color class, is a high-performance LED display screen. If the gray series deficiencies, lack of hierarchy or color will occur is gradient color gradation is not very smooth, but can not fully show the color film. LED display screen effect greatly reduced. Some of the low efficiency of the LED display screen in the 1/500s shutter, you can check out the obvious color distribution, if we increase the shutter speed, such as 1/1000s or 1/2000s, the situation will be more obvious.

What is the impact of the LED screen refresh rate and gray level?

We know that LED screen several core components, such as LED switching power supply, LED drive chip, LED lamp, the refresh frequency and gray level LED display, LED driver chip directly determines the LED screen frequency, gray level refresh in visual performance. In the current LED driver chip, the high technology “ScrambledPWM (S-PWM) technology, S-PWM technology is to improve the traditional pulse width modulation (PWM) technology, which will be an image conductiontime dispersed into a number of shorter turn-on time to increase the overall visual update rate. Further, a new generation of LED driver chip built-in S-PWM technology, can be originally each frame (frame) counting time (LED ON, LED OFF grain grain) way, broken down into several average counts, and each scattered parts, can not maintain the original scattered before the ratio of On/Off. As shown below.

S-PWM technology provides a different counting mode, so the image refresh rate can be raised to a maximum of 64 times. If replaced by S-PWM to improve the image refresh frequency of the operation, just use a low order clock (such as 5MHz) can be easily refresh the visual refresh rate 64 times, and can reach more than 4800Hz. Compared to the general video refresh rate of at least 10 times higher than the capacity, but also to avoid the occurrence of high frequency electromagnetic interference (EMIissue), over-voltage surge (Overshoot) and under voltage surge (Undershoot) problem.

S-PWM driver chip LED display, with a digital camera high-speed shutter to take photos, there will still be no horizontal black scan line and color distribution (as shown below). Its visual refresh frequency, the performance of gray level, far beyond the use of traditional switching type driver chip LED display.

High quality LED driver chip, built in S-PWM technology, making the refresh rate of up to 3840Hz, gray level up to 16bit, in the case of high-speed shutter camera, after the emergence of the level of black scan lines and color distribution

Optokingdom Engineer shares LED Display Module 7 Core Parameter Analysis

The LED display module is the core part of the display, it is equipped with a LED circuit board and the shell, and the LED lamp is arranged together are packaged according to certain rules, then add some water treatment and a product composition. With the continuous development of LED display industry and the growing demand for applications, the function and role of the LED display module can not be ignored.
full color led display screens
So, today we come to understand the LED display module under the seven parameters:

1.LED panels module color

It is the most basic parameters in the LED panels module, the application of different colors in different occasions. According to the variety of colors can be divided into single color, full-color single point of control of two.

1), monochromatic is a single color, can not be changed, then the power can work.

2), full color is single point to each module can control the color, to achieve a certain degree of time can display pictures and video effects on the number of modules. To add a full-color single point control system can realize the effect.

2.LED display module brightness

One to the brightness, we think of the word high brightness, this parameter is a parameter that people pay more attention to. Brightness in the LED inside is a complex problem, we usually say in the LED display module brightness is usually luminous intensity and transparency, is generally related to the degree of each module can be summed up.

3.LED display module light angle

No LED display module with lens light angle, mainly by the LED lamp to decide different light angle LED lamp emitting angle is different, generally provided by the manufacturer for LED lamp module angle.

4.LED display module operating temperature

The normal working temperature of the LED screen module is usually between -18 C and 58 C, if the requirements are relatively high, it is necessary to carry out special treatment, such as air conditioning or exhaust fan.

5.LED screen module voltage

It is one of the most important parameters in the LED screen module, and the low voltage module of 12V is more common. In connection with the power supply and control system must check the correctness of the voltage value, in order to power, otherwise it will damage the LED module.

6.LED module size

Usually refers to the length and width of the higher dimensions.

The maximum length of a single connection: this parameter when we do large projects with more than, it means in a series LEDscreen module, a LED screen module is connected. This is related to the size of the connection line of the LED display module. Also according to the actual situation to customize.

7.LED module waterproof level

This is mainly for outdoor, it is to ensure that the LED display module can be an important indicator of long-term work in the open air. Usually in the case of open air the best waterproof level to reach IP65.

Optokingdom engineer teaches you how to Troubleshoot your LED screen

When using LED screens it is inevitable to face some problems sometimes. Now Optokingdom engineer would like to tell you how to distinguish and determine the LED display fault diagnosis.

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1.Check if the graphic card settings is well or not, according to the instruction in the CD-ROM electronic file.

2. Check the basic connection of the system, such as DVI cable, network cable, the sending card and computer PCI slot, and the serial cable connection.

3. Check if  the computer and LED power supply system have met the needs or not. When the LED screen’s power is low, the LED screen flicker when it show only white color. You should use appropriate power supply according to the actual needs.

4. Check whether the green light of the sending card has a regular flashing, if flashing see next Step 6 directly, if not flashing, restart. Before entering the win98 / 2k / xp please check the green light is flashing regularly or not. If  flashing, please turn into Step2, to check if the DVI cable is connected properly. If the problem is not resolved, then there must a problem of the sending card, the video card and the DVI cable. please repeat step 3 after replacing one of them.

5. Follow the instructions of the software to set or re-install and then set until the sending card green light flashes, otherwise repeat step 3.

6.Check whether the green light (data light) of the receiving card is flashing synchronously with the green light of the sending card. If it blinks turn to Step 8, check that the red light (power) is on. If it is on please turn to Step 7, If the power supply is not on, check if the power supply is reversed or the power supply doesn’t have output. If the power supply voltage is 5V, turn off the power supply, remove the adapter and cable to try again, if the problem is not solved for the receiver card failure , Replace the receiving card, repeat step 6.

7. Check whether the network cable is connected well or too long (you must use the standard CAT5 network cable, the network cable without repeater is the longest distance and 100 meters). Check whether the cable is made according to the standard (see the system installation and setup ), If the problem is not resolved to receive card failure, replace the receiving card, repeat step 6.

8. Check if the LED screen power light is on. If not, go to step 7 and check that the interface of the adapter card matches the LED module.

More Troubleshooting tips about your led display please visit our website http://www.optokingdom.com/user-manual.html

We are the most trusted online store for HSTV LED Display,LED screen,led wall,led signs and led panel. We offer the highest quality of LED Screens, Displays,signs,panels suitable for both indoor and outdoor advertisement.

HaiSheng Firmly Believe LED Display Market full of Sunshine,As Supplier & Buyer in Synchronous

Now many LED Display manufacturers complain that the world LED Display Market become dull ,depressly and backward !But after profound understanding and calm reflection, our HaiSheng LED Co.,Ltd deeply realized that the international LED Display Market must be full of sunshine,as soon as the buyer and seller in synchronous.
(I.)Quality Consciousness in synchronous:
Both buyer and seller must pay the most attention on the quality ,the international LED Display Market will be full of sunshine. When bargaining price,both buyer and seller forget the quality important.When happen quality problem,both of them are going to argue hotly and blame each other sharply !Why does this kind of scene happen? The main reason is profit maximization.When buyer want to make more profit ,they cut price cruelly,they forget the the important quality.When seller want to get order and make more profit,they are cheating on workmanship and materials,they forget the most important quality too !
Both buyer and seller must pay attention on the quality consequences!For example,when buyer purchase 10 pcs Traffic LED Display,after 10 days they fixed them on Highway,the LED Display start to sparking ,stimulate and harm the driver’s eyes ,in this way it is very easy cause the traffic accident.So in short there is very big market require the LED Display,but because of the consumer worry about its quality,they will not choose to use the LED Display.
Only when the buyer and seller realize the most important quality in synchronously,the LED Display Market will become bigger and bigger !
ShenZhen HaiSheng LED Co.,Ltd insist on the Policy of “The Quality First,The User Supreme” .We always pay the most attention our factory LED Display quality !Our only wish is that we are the trustworthy manufacturer to our consumers!We regard All over the world consumers as our friends,sisters and brothers! Welcome you cooperate with us hand-in-hand warmly !We will suply you the international first class quality products and the best serive ! To supply you the convienence is our happiest !


(II.)Price Consciousness in synchronous:
Even I do do not need to say anything,both buyer and seller must pay the most attention on the price,because they get profit from the price.
But when both buyer and seller bargain the price,pls do not forget Consciousness in synchronous.The seller must know clearly that foreign buyer must pay for sea or air freight,declear custom,pay for tax ,pay for warehouse or shop rent and staff salary.On the other hand,the buyer must know clearly that seller have to pay for material ,factory working site rent,water,electricity cost,have to pay for tax ,worker and staff salary.Both buyer and seller have to pay for expense ! But the buyer ususally cut the price sharply,the seller have to face the fierce market competition,if he does not accept this order,the other factory maybe accept this order.Then he is forced to accept this order,he take a risk and attempt to to cut corners for making little profit. Then at last happen the big accident.
For example,a HK customer buy 1pc Outdoor Aluminium Decorative LED Display from Mainland,for the cheapest price ,he lost the biggest face ! After a few days he fixed it on a facmous building,the LED Display burst into flames.It not only makes safe problem,and make the building look very ugly ! The building facade become black ! As soon as HK citizens walking along the road and look the black building feel very afraid.So when buyer and seller bargain price,pls do not forget to guarantee the quality !
Our HaiSheng Co.,Ltd remember the quality is a factory’s life ! Our factory ‘s Outdoor Aluminium Decorative LED Display is fireproofing,anti-corrosion,windbarrier,provide you a safe protection ! It is light in weigt,free in noise,easy installation,beautiful design and bring you the wonderful enjoy imaginning life ! Welcome all over the world friends contact with us warmly ! Let’s enjoy the happy lfe together !

HaiSheng LED CO.,LTD Predict The 2017 LED Display Market Trend

In near these years, with the continue developing of LED display market optimization, the enterprises make full use of LED display feature and product differentiation .The market developing trend is obvious, and it become the way which LED display enterprises enhance core competitiveness and win greater space for development . HaiSheng LED CO.,LTD tell you that 2017 LED display industry market trend is going to be as following:

1.Innovative led screen are blossoming in radiant splendour.

2.Small pitch LED display market is leading cutting-edge market development.

3.Indoor led display market continue to be occupying in new applications

4.Transparent LED Curtain Display will bring the new view of outdoor media market.

5. Rental led display market has the great growing potential.


LED Display industry market analysis:

During 2016-2021, China LED display industry market demand and the investment advisory report predicts that the next few years, the global LED display market demand is going to continue to maintain rapid growth, the average annual growth rate is going to exceed 20% expected by 2020, the global LED Display market scale is going to reach 30 billions US dollars, China is going to be the most important manufacturing base.
LED Display industry market prospect:

We are outdoor & indoor led screen solution supplier and manufacturer
Of every kind of led screen. If you need any advertising led display with the cheapest price and the best quality, welcome you feel free to contact
With us any time or visit and register in our website www.optokingdom.com .We are dedicating 9 years in the field of the production of LED display ,providing fixed installation and rental LED displays,Decorative Aluminum Led Curtain Screen, LED strip curtain display, Transparent LED Display. All our Product are CE certified & ISO 9001:2000.We have confidence on our factory products the best quality and the best service !

HaiSheng LED CO.,LTD Teach You to Identify LED Display Quotation Avoiding Unreasonable Price

When buying a led display, we always ask a quotation as a reference, so that can estimate the project cost and know whether the budget is overrun.

With years of experience, HaiSheng LED CO.,LTD here will give you details of the LED display quotes included cost to help you buy LED screen with a clear and intuitive understanding.

p10 led display P6-Module-64 x32 (3)

1. The Screen body cost: Is generally based on how much money per square meter, that is, you can see LED display offer xxx $ / m2, different display model, the materials used, the price will be different. Screen quotation includes a full set of LED screen required: die, module circuit board, IC driver chip, power module, steel box and plastic mask and display all internal flat cable, connecting line and so on.

2. Control system costs: Sending card and receiving card costs, one screen is generally only use a sending card, installed inside the host computer, There are countless receiving cards. The number of control card is determined according to the size of the screen. Generally speaking, the larger the area, the higher the density of the display, will use more receiving cards.

3. Control computer: control LED display of the necessary equipment, requires configuration requirements or higher: dual-core CPU, 2G memory, 512M or more discrete graphics, motherboards have PCI slots.
(If you already have one, you can ignore this part of the cost)

4. Sound + Amplifier: Let the display sync video playback sound of the equipment, generally equipped with an amplifier, 2 stereo.(not necessary,basis your real need)

5. Power distribution cabinet: Small area LED display doesn’t need to use; recommended using on the display with maximum power consumption of more than 10KW power ,It can Provides a voltage source current for the operation of each device of led display, effectively prevent the display power switch for the jump Box and other failures.

6. Air conditioning: cooling equipment, traditional outdoor LED display more than 20m2 manufacturers must be configured by air conditioning to ensure the normal operation of the screen body and extend the life of the display device. Large indoor display screen is strongly recommended with wall-mounted air conditioning, effective cooling, to ensure that the normal high-temperature display under the line, reduce the failure rate.(HaiSheng LED Co., Ltd launches several new product auto cooling such as Led Strip Curtain Display, Decorative Aluminum Led Curtain Screen, Transparent LED Display, they Do not require air conditioning cooling)

7. Multi-function card: Indoor led display, the main role of sub-time intelligent adjustment led full color display brightness, temperature and other values, intelligent regulation to achieve energy saving, extend the life of led display; outdoor led display do not need to use .

8. Arrester : Usually use on outdoor LED display, mainly anti-lightning protection devices; indoor led display do not need to use.

9. Video capture card: TV card, a small card, installed in the computer, coupled with the appropriate driver software that allows the display simultaneously broadcast cable TV channel programs, buying or not it depends on the user’s needs, inexpensive.

10.LED video processor: Mainly to improve the large overall display and functional applications, and fully tap the value of the display. To solve a variety of video signal access, processing and display problems, to complete the format conversion between the many signal formats. LED video processor brand and model number, price varies.

11.LED playback software: including computer system software, LED video player software. It’s free.

12.Freight: Different countries, different product weight, will lead to different costs, I believe that the majority of customers can accept.

The above is about the led display cost should include in the quotation.Knowing these can avoid you from price trap.


HaiSheng LED Co., Ltd – Market Leader Among LED Display Screen Manufacturers. Supplier of outdoor & indoor LED Display Various Types to Meet Your Choice.You also can visit our one-stop online shopping mall optokingdom.com to check led display price directly, Estimate project cost by filling in width and height of screen, system will automatic estimate cost for you.
We offer Project Free design for our customer,specific solution sent to you by filling project information on it. Visit this page:

All we do is offering time saving, safe, convenient and qualified one stop service to our clients.

HaiSheng LED CO.,LTD. Give you some tips to maintain the transparent LED display in daily!

Surprisingly, the transparent LED display is a popular product in our company! Because our company focuses on producing the transparent LED display of high rate of perspective, the light weight and the unparalleled pixel pitch! At present, in the high-grade office buildings of city center, commercial complex, windows and other places have begun to gradually apply the transparent LED display. In the process of using the transparent LED display, how should our customers to maintain it in daily? Now let me give you some tips!


  1. Screen body is strictly prohibited the water, the iron powder and the other conductive metal. Thetransparent LED display should be placed in a low dust environment. Because the large dust will affect the display. At the same time, if it has too much dust, it will cause damage to the circuit.
  2. Whenit’s flooded with various reasons, please turn off the power immediately and contact the serviceman. You can use it until the screen body is dry.
  3. When the surface is stained with dust, please clear it with the vacuum cleaneror the air gun facilities. Do not wipe directly with the rags and othe In order to prevent the body from falling off, you can’t operate it with force.
  4. In order toprevent damage to the product surface, you can’t wipe with cloth which it is too hard, rough or dirty.
  5. It suggested that the rest time of thetransparent LED display must be more than 2 hours a day. In the rainy season, you can use it at least once a week. Generally, you should open the screen at least once a month and lighten it more than 2 hours.
  6. Need tohave a regular check whether it is in the normal work, whether it has the damage to the line. If it can’t work, it should be replaced in a timely manner. When the line is damaged, please repair or replace the damaged line.
  7. For the sake of prevent to cause the current and the power cord heat is too large,you can’t play for a long time in all yellow, all red, all green, and the other full screen. When the LED lamp is damaged, it will affect the display life.
  8. Do not disassemble, splicing screen body.
  9. If the Internal wiring is caused the failure, please contact the service manimmediately.


These are my suggestions for you! Haisheng LED CO.,LTD. can offer the transparent LED display of the high quality and the affordable price to you! And we can provide the professional service and guide to our customers! You can see more at: http://www.optokingdom.com/Transparent-LED-Display-c2098.html

The share from Haisheng— The design of the lifting stage in Spring Festival Gala! (Chapter 2)

The characteristics and the horizontal layout of the lifting stage in Spring Festival Gala makes us very surprised, do you know the structure of the stage and the difficulties in design and installation? Now let me tell you!


Part 3: Structure of the stage

Because No.1 CCTV Studio is an existing building, the installation of the equipment just can rely on the method of “expansion” on the scene. The all single machine equipment are installed on two channels. Between the channel steel and the ground is connected by expansion. According to the characteristics of small size and difficult structure arrangement, it adopted the program which use the geared motor to drive the gears directly. The power is transmitted from the drive gear to the other pair of gears. Consequently, with the drive of the gear, the middle frame can run. At the same time, the middle steel frame, fixed steel frame and LED steel are connected together with the chain. The chain is formed into a closed chain. Because the fixed steel frame can not exercise, with the operation of the middle frame, LED steel will run. Between LED screen and LED steel frame is connected by the screws. The control of the travel and the speed of the elevator is based on an encoder which is mounted at the end of the motor.


Part 4:Difficulties in design and installation

1.Difficulties in design

The difficulty in design is the shaking of fixed steel frame. If the design is not reasonable to shake, it will bring great security risks to the show. The biggest obstacle to solve the problem is that the space is insufficient. At last, it carried out the physical trial and the measurement through the steel frame mechanical calculation tools.

  1. Difficulties in mechanical installation

Accuracy of installation position and operation precision is the difficulty in mechanical installation. The requirement of the verticality is so high after the installation of the single device. If it is skew, the lifting platform must rub each other. Seriously, it will damage to the LED screen. Because the lifting table is the vertical and horizontal arrangement, when the position is skew, it must affect the gap between front and back or left and right lifting platform. It will cause a 0 gap, too large a gap or a negative gap. Therefore, the uniformity control of the gap must be accurate between the each lift table. After the strict quality checks, the clearance of the lift is controlled within the allowable range.


The design of the lifting stage in Spring Festival Gala is innovative and scientific! As an excellent supplier in LED industry, Haisheng company has rich experience in design of the stage solution for 8 years! We offer over 500 stage projects’ devices! Our company boasts with comprehensive products lines of stage, including stage led lighting, amplifier and speaker equipment, stage led lighting consoles, dance floor LED screen, complete stage project equipment, LED ceiling display and stage rental LED display etc. We can meet your personalized requirements and provide the professional service and guide to our customers! You can see the products at: http://www.optokingdom.com/

The share from Haisheng — The design of the lifting stage in Spring Festival Gala! (Chapter 1)

  In the Spring Festival Gala on CCTV, not only did the changeable lifting stage left a deep impression on hundreds of millions of viewers in front of the TV, but also it brought a new concept of the stage! It will bring revolutionary changes to the stage design in the future, especially the stage design of the television studio!


Part 1:Characteristics of the stage

There are four characteristics in Spring Festival Gala:

1.Work closely with actors or plot.

Whether the traditional stage exercise or not, the host or actor should stand or perform in accordance with the fixed position of the stage. When it needs the movement with the stage, the actor must in a fixed position on the stage. The stage occupied the No.1 CCTV studio in Spring Festival Gala. In addition to the area for audiences, the lifting stage which is composed of 304 lifting tables, it is full of every area where the actor will reach. So as long as the actors in the performance area, no matter where you are, the lifting stage can run with the actor according to the needs of the plot. It can change from the traditional sense of the person or the scene of the stage into a stage or landscape.

2.Fast and changeable combination.

It didn’t increase or decrease any props and scene on the stage in Spring Festival Gala. It just change the combination of the lifting platform and the video content of the LED screen. Each program has its own “scenery and props”, it can achieve them through the organic combination of the lifting platform and the change of LED screen video content! Although the change of each scene or situation just use a few seconds, it can make people to be personally on the scene and feel real!


3.Participate in performance.

Because the size of each lifting platform is small, it is up to 304 blocks. Not only the lifting stage plays the role in manned scenery, at the same time, but also it involved in a variety of performances. In the whole Spring Festival Gala, almost all the lifts are running to work in with the actors and performing to enjoy hundreds of millions of viewers. With the change of the story, the lifting platform plays a important role in performing.

4.Embodiment of scene and props.

Because the surface of the lifting platform is paved with the LED screen, and the LED screen is connected to the video control system. Therefore, when it is combined with the combination of lifting platform, it can create richer scene and props!

Part 2:Horizontal layout of stage.

No.1 CCTV Studio is a circular structure. The lifting stage is arranged in long strips. The length from front to rear is 34.835 meters. It is almost the entire length of the studio. The width from left to right is17.41 meters. The width is also exceed some theater stages. The whole performance area is all the lifting stages. The basic size of the lifting platform is 1m * 1m. There are 266 pieces of these basic lifting platforms. It accounted for a total of 87.5%. The lifting stage group is composed of four kinds of specifications.

The design of the lifting stage in Spring Festival Gala is changeable!


The products of the stage is various in our company. There are the outdoor rental LED display with PH3.91-PH16, the stage project products and the stage LED light with a variety of models. Our products can meet your personalized requirements! If you want to know more products about our company, you can enter to our website: http://www.optokingdom.com/


LED advertising large screen

The market of LED advertising large screen is growing consistently. From the growth rate of the market , the technology of LED advertising large screen continues to introduce new products.

The technical range of LED advertising large screen includes the semiconductor optoelectronic device technology, the electronic circuit technology, the integrated circuit technology, the information image processing technology, the information transmission technology, the computer network technology, the manufacturing of electronic products and the installation engineering of electronic products.


Due to the rapid development of semiconductor industry, the invention improves the manufacturing material of the light emitting diode and the manufacturing process. It has a qualitative leap in color and brightness. The high brightness of blue and pure green light-emitting diodes have the large-scale production and they have been applied. At present, LED advertising large screen can meet the requirements of different environment from indoor and outdoor. The red LED device of four elements and the high brightness blue of pure green are widely used in outdoor displays. LED device which is used of the technology about on display screen can get a better view and brightness. At present, it has been applied in high density and full color indoor displays. But the cost is relatively high. With the decrease of the cost, it will have a relatively large market potential in the future.


In order to make the display in line with the visual characteristics of the human eye, it appeared the technology of Nonlinear Grade Difference Gray. Through the technology of Nonlinear Grade Difference Gray, the effect of display is more real and delicate. In fact, by the constraints of the data and the image of the source, the actual value in use is meaningful to pursue a large quantities of gray control. The design of the driver circuit is based on general-purpose integrated circuits which is widely used now. The principle is relatively simple. The technology of products is relatively strong and the price is cheap. The driving circuit for universal IC design is mature in monochrome, dual color of the displays from indoor and outdoor. It is still the main driving circuit nowadays. In recent years, the constant current drive IC has been developed rapidly and they also widely used. It greatly improve the uniformity of LED display. At the same time, it reduces the capacitance of the display driving circuit and the fault point. It makes LED advertising large screen more reliable and more beautiful !