Advantages and disadvantages and development trends of LED display DIP, SMD and COB

one. DIP display

DIP package, short for dual inline-pin package , commonly known as plug-in display. It was the first of the three package modes. Lamp beads are manufactured by packaging LED lamp manufacturers, LED module and then by display manufacturers to insert it into the LED lamp board PCB, after wave soldering DIP produce semi-outdoor and outdoor modules waterproof module. In the beginning, the red, green and blue lights were inserted into the PCB to form an RGB pixel. In the later stage, the RGB three chips can be packaged in a single lamp bead, that is, a three-in-one outdoor display, which is relatively improved. Production efficiency and production costs. However, regardless of the single-lamp RGB or 3-in-1 RGB, the dot pitch is limited by the diameter of the lamp bead. At present, only P6 can be achieved, and it is difficult to achieve a higher density outdoor display SMD LED lamp beads. The protection performance is good, but the viewing angle is not accurate and fixed, generally between 100-110 , so it is suitable for outdoor large-distance display.

DIP display currently appears to be more complex in production organization, difficult to implement mechanized production, and production efficiency. The quality of the display screen is subject to the quality of the lamp bead in the lamp bead packaging factory. Each batch is not well controlled, so the quality is not well controlled. In addition , there are many DIP manufacturers, there is no high technical and equipment threshold, and the competition is fierce. Many manufacturers use inferior raw materials and PCB boards to reduce the cost to gain market share, low quality, and almost no perfect after-sales guarantee.

DIP products are relatively rough in appearance, with a viewing angle of only 100-110 degrees, low quality, high energy consumption, no environmental protection, and low price. Currently, they can occupy a strong market share in the outdoor P20-P8 market.

2. SMD display

SMD package, a Surface Mounted Devices acronym meaning: surface mount devices, it is SMT (Surface Mount Technology Chinese: Surface Mount Technology) components of. “In the initial stages of electronic circuit board production, via assembly was done entirely by hand. After the first automated machines were introduced, they could place some simple lead components, but complex components still required manual placement for wave soldering. Surface mount components were introduced about twenty years ago and have opened up a new era. From passive components to active components and integrated circuits, they have finally become surface mount devices (SMD) and can be accessed by pick and place equipment. fitted in a long period of time that all people may eventually lead elements SMD package. SMD technology used widely in the LED display.

Three-in-one is a kind of LED display SMD technology, which means that SMT lamps of RGB three different color LED chip packages are packaged in the same glue body at a certain pitch . Full-color LED display using three-in-one SMD technology The screen view angle is relatively large relative to the DIP , and the surface can be treated by light diffuse reflection, and the obtained effect is not granular, and the uniformity is good. In terms of color, the three-in-one full-color splitting color separation is easier than the three-in-one, and the color saturation is high. The three-in-one uses the entire surface to illuminate , so the overall color of the three-in-one is more uniform. The overall flatness of the three-in-one is easier to control. It has always been the standard technology used in HD LED displays.

In the early stage of development, because of the complicated manufacturing process and difficult maintenance, the cost is very high, and it is generally used for high-end LED display products. In recent years, due to the rapid development of three-in-one technology and continuous improvement of production technology, a large number of automatic equipments have been used. SMD has developed rapidly and the cost has been reduced. It is the mainstream product of LED indoor display. And it has begun to penetrate into the outdoor display market, but the brightness and outdoor waterproof, moisture, dust, anti-static, anti-oxidation has always been its insurmountable gap.

three. COB display

The COB package, short for Chip on board , is a new package that differs from DIP and SMD packaging technologies. Wei Qiaoshun Optoelectronics pioneered this technology in the field of LED display. After years of technical practice, it is the only manufacturer that has mastered this technology and serialized and mass-produced its products. We have hundreds of derivatives based on COB's patented technology. The key to Wei Qiaoshun's patented technology lies in the COB package + lamp drive.

Compared with the previous dot matrix module , DIP and SMD , Wei Qiaoshun's COB display has the following significant advantages.

1. Ultra-thin: according to the actual needs of customers, using a thickness of from 0.4-1.2mm thickness of the PCB, so that the weight is reduced to a minimum of 1/3 of original traditional products, customers can significantly reduce construction, transportation and engineering costs.

2. Anti-collision and compression: COB products directly encapsulate the LED chip directly in the concave lamp position of the PCB board, and then encapsulate it with epoxy resin. The surface of the lamp point is convex into a spherical surface, smooth and hard, and resistant to impact. mill. Even if there is a bad point , the COB product can be repaired point by point, and the repair is very simple.

3. Large viewing angle: traditional LED display, first of all, the LED chip is at the bottom of the lamp cup, forming a certain gap between the cup and the cup, and then the accuracy of the position of the packaged lamp in the process of patching, and the unevenness of the mask again. For three reasons, the viewing angle is reduced and the viewing angle is not uniform. DIP 's viewing angle is 100-110 degrees, SMD 's viewing angle is 120-140 degrees, and COB package uses shallow well spherical illumination, viewing angle is greater than 175 degrees, close to 180 degrees, and has better optical diffuse color than SMD. effect.

4. bendable: COB package bendable ability unique characteristics, bending of the PCB without causing damage to the packaged LED chip, the SMD may cause bending of the PCB sealing off the chip pins. Therefore , the LED arc screen, the circular screen, and the wavy screen can be conveniently fabricated using the COB module . It is an ideal substrate for personalized screens in bars and nightclubs. It can be seamlessly spliced, the production structure is simple, and the price is much lower than that of the flexible circuit board and the LED display screen made by the traditional display module . The high-density P4 series module has a cylindrical bending capacity of 50cm in diameter and is an ideal substrate for cylindrical media in airports, stations and shopping malls.

5. Strong heat dissipation: SMD and DIP products mainly dissipate heat through colloids, lamp legs or pads. The heat dissipation area is small, and the heat will be concentrated on the chip. It will cause serious light attenuation and even dead light phenomenon for a long time, which reduces the display. The life and quality of the screen. The COB product is a PCB board on which the lamp is packaged. The heat of the wick is quickly transmitted through the copper foil on the PCB board, and the thickness of the copper foil of our PCB board has strict technical requirements, plus the immersion gold process, the PCB board. the price is the same size SMD and DIP 2 times. That's why our COB products are hotter to feel, and they are very hot, indicating that heat is easily emitted and hardly causes severe light attenuation. Therefore, there are very few dead lights, which greatly extend the life of the LED display. In terms of structural design, Wei Qiaoshun Optoelectronics also used aluminum trays to replace the traditional SMD and DIP plastic brackets, plus some auxiliary and effective heat dissipation means to quickly discharge heat.

6. High stability: The high reliability of Wei Qiao Shunguang 's COB products is reflected in the module's dead rate rate has been controlled at <5/100000, far higher than the national standard. There are the following points to ensure that we are not difficult to achieve this standard, or even better.

A. Production process: The processing technology of traditional LED display screen is quite numerous, especially in the process of reflow soldering. Under the high temperature state, the expansion coefficient of SMD lamp bead holder and epoxy resin is different, which is easy to cause bracket and epoxy resin. The package shell is peeled off, and a gap occurs. In the later use, the dead light phenomenon gradually appears, resulting in a high defect rate. The reason why the COB technology display is more stable is because there is no reflow soldering lamp in the processing technology. Even if there is a post-reflow soldering IC process, the diode chip has been cured and protected by epoxy resin, which avoids it. The problem of gaps between the lamp holder and the epoxy resin caused by high-temperature soldering in the welding machine, so our COB products are not prone to dead lights after leaving the factory.

B. Use of high-end manufacturing equipment: We use the most advanced ASM automatic welding equipment.

C. Strict quality control throughout the process:

D. Wei Qiaoshun's business philosophy: We convert the cost of using advanced production processes to provide customers with the highest quality raw materials. For example, our PCB board adopts the immersion gold process, and the price is twice that of the traditional module of the same specification. Usually we use larger chips and better ICs, and we use better heat sinking materials in the structure.

7. Six anti-advantages: waterproof, moisture-proof, dust-proof, anti-static, anti-oxidation, anti-UV is a weakness of SMD products, it is indeed the strength of Wei Qiaoshun products. The LED pad of the traditional LED display is bare. When it is wet or damp, it is easy to short-circuit between the lamp pad. The mask used is uneven and it is difficult to clean it when it is dusted. The alloy wire and iron bracket are easy to be used. Oxidation; exposed lamp pad is susceptible to static electricity and a dead light. The COB protects the chip with epoxy resin. It has no exposed lamp legs and can function as waterproof, dustproof and antistatic. When it comes to water, just wipe it with a cloth. The outdoor module is not afraid of water at all, and has no effect on the screen. After using for a period of time, the dust of the screen body can be directly wiped with a rag, and the dust is directly cleaned from the smooth surface. In addition, Wei Qiaoshun COB module uses the circuit board of the immersion process, and special treatment process, which can resist oxidation and ultraviolet rays. Wei Qiaoshun's COB module can work normally at temperatures as low as minus 30 degrees and at temperatures as high as 80 degrees above zero .

8. Energy-saving highlighting: At present, SMD is fiercely competitive. LED strips are commonly used for small chips. When used normally, the load of the lamp is high, the brightness is not up, and the brightness attenuation coefficient is large. After using for a period of time, the consistency will be Significantly worse. The COB products of Wei Qiaoshun Optoelectronics use large-chip LEDs, which can effectively improve the brightness, uniform heat dissipation, and small brightness attenuation coefficient. It can ensure good consistency after long-term use. With the same brightness, COB heat is smaller and more energy efficient.

The only drawback of the COB package is that the ink on the screen is not well controlled, so God is fair. At the same time, it gives all the benefits of COB , but also chooses a problem that makes COB a headache; but this does not affect the COB display. Excellent performance. Fortunately, we have found ways to improve the color of the ink.

At present, Weiqiaoshun Optoelectronics' products have entered the COB outdoor high-density high-brightness full-color range. Our products have an absolute advantage over traditional products. At the same time , they have unique advantages in indoor and outdoor LED shaped screens and creative modeling screens. The display engineering module can overcome the dot matrix module unit board, and has the advantage of surpassing the SMD quality in the indoor full color screen . It has an absolute advantage in indoor and outdoor ultra-thin and ultra-thin double-sided screens.

Therefore, the development in the next few years will be the era of the male and female elk. The dot matrix module will gradually fade out of the market due to the backwardness of the products and the inferior quality of the manufacturers. In the field of outdoor display, the P20-P10 market is still the world of DIP , but the market share is gradually shrinking due to the outdated product technology, and the P8-P6 will be the mainstream development market. Two points by SMD and COB . In the outdoor P5-P4 high - density and bright full-color market, there will be COB- led. SMD has a place in the low-end of indoor screens . At this time, because of the fierce competition, SMD may have the same destination as the dot matrix module. In terms of indoor high-end small spacing, COB products will have an absolute advantage. COB products have absolute advantages in indoor and outdoor shaped screens and creative modeling screens .

Therefore, the future is the era when quality is king, benefit is king, function is king, and service is king.

A lot of quantity, the price is very low, no benefit, no quality, no differentiation, it will die very badly!