"Analysis of Key Points on COB Packaging Technology"

Small-pitch LEDs have begun to continue to break through the upper limit of ultra-high-definition displays, and the various limitations presented by SMD in the field of micro-pitch have made the contribution of COB technology more and more prominent. In the past few years, COB was just an emerging term, but in the rapidly developing LED industry, COB has now become the mainstream development direction, and COB's support for ultra-high-definition display has become an important development trend in the display industry.
01 Flip VS Dress Technology

COB 技术自身所具备的优势已然成为市场关注的焦点，而倒装 COB 更是将 COB 技术提升到了一个全新的高度。COB itself belongs to a multi-lamp bead integrated stent-less packaging technology. It directly packages the light-emitting chip on the PCB board, eliminating the need for complicated surface mount processes and eliminating the solder pins of the brackets. The LED chip and solder wires of each pixel are tightly and completely encapsulated in the glue by epoxy resin glue, without any exposed elements. This provides effective protection for the LED chip and can solve the problem of external factors on pixels. Damage caused by points. Flip-chip COB can greatly increase the current density and enhance the stability and light efficiency of lamp beads. The flip-chip structure can well meet such needs. Based on the advantages of micro spacing, high reliability, and non-glare of surface light sources of formal COB, the reliability is further improved, the production process is simplified, the display effect is better, and the chip-level spacing can be achieved to reach Micro LED level.
02 Co-negative VS co-positive technology
Conventional LED displays adopt a common anode (positive electrode) power supply method, and current flows from the PCB board to the lamp beads. Common anode lamp beads, corresponding driver ICs, and RGB lamp beads are used for unified power supply. The common cathode refers to the common cathode (negative electrode) power supply method. It adopts a common cathode lamp bead and a special common cathode driver IC solution. R and GB are supplied separately, and the current passes through the lamp bead and then to the IC negative electrode. After adopting common cathode, we can directly apply different voltages according to the different voltage requirements of the diode, so that there is no need to configure a voltage dividing resistor, which reduces this part of energy consumption. However, the display brightness and display effect will not be affected, and the energy saving effect can be improved by 25% to 40%.
03 Create standardization of ink
Committed to creating the consistency of pure ink, the black area of a single pixel is as high as 99%. It adopts top panel ink treatment technology and surface non-reflective treatment technology. The surface of the pixel points is smooth and hard, and has anti-knock, anti-impact, shockproof, pressure resistance, waterproof, moisture-proof, dustproof, oil pollution, oxidation, anti-static and many other excellent properties. It has a high degree of stability and easy maintenance, and can bring a wonderful visual experience. When a black screen, The consistency of the entire screen is even better.
04 Effectively reduce moire patterns
The COB packaged micro-pitch LED display adopts a high fill factor optical design, emits uniform light, similar to a" surface light source", and can effectively reduce moire patterns. Its matte coating technology also significantly improves the contrast, reduces glare and glare, and effectively resists blue light damage. It not only reduces human visual fatigue, but also can take high-definition videos or photos under camera or camera shots., especially suitable for applications that require long-term viewing and screen shooting (such as lecture halls, studios, etc.).
05 Reliable protection reduces bad dot rate
COB packaging technology encapsulates pixels on a PCB board, realizing comprehensive sealing of the PCB circuit board, crystal grains, solder feet and leads. The surface is smooth and has no exposed components, achieving full IP65 protection capabilities. The surface of the pixel points is smooth and hard, with excellent performances such as anti-knock, anti-impact, shock-proof, anti-pressure, waterproof, moisture-proof, dustproof, anti-oil, anti-oxidation, and anti-static. It is highly stable and easy to maintain. It can be used directly during daily cleaning and maintenance. Use a damp cloth to wipe off surface stains. The COB packaging process allows the bad dot rate and the out-of-control rate of the entire screen to be controlled below one in a million. The fanless design not only reduces noise, but also reduces failure points, effectively ensuring that the screen will hardly be used. No maintenance costs are incurred.