First, let's explain the full names of GOB and GOB. COB (Chip on Board) and GOB (Glue on Board) are two packaging technologies for LED display screens, which have significant differences in process, performance and application scenarios. The following is a detailed comparison of the two:
1. Let's explain their differences from the packaging process
COB LED screen technical principle: The LED chip is directly bonded to the PCB board and encapsulated by laminating (epoxy resin or silicone), eliminating the bracket and reflow soldering steps of traditional SMD.
COB LED screen packaging process features: The chip is in direct contact with the substrate, the structure is compact, there is no exposed solder joint, and the protection is stronger.
GOB LED screen technical principle: A transparent glue layer (such as high-transmittance silicone) is coated on the surface of the traditional SMD LED module to form a protective layer to enhance protection.
GOB LED screen packaging process features: Based on the improvement of SMD process, the problem of insufficient SMD protection is compensated by gluing.
2. Core differences
Technical basis: COB LED screen is a direct encapsulation chip, and it has no SMD bracket. GOB LED screen is based on SMD process, with additional glue reinforcement.
Protection capability: COB LED screen is dustproof, waterproof, impact-resistant, and suitable for harsh environments. GOB LED screen has better protection, but its protection performance is weaker than COB.
Heat dissipation performance: COB LED screen adopts chip direct contact PCB design, which has better heat dissipation. GOB LED screen relies on SMD heat dissipation design, and the glue layer may affect heat dissipation.
Pixel pitch: COB LED screen can achieve 0.63mm pitch, but GOB LED screen is limited by SMD process, and its current pixel pitch remains at 1.25mm
Display effect: COB LED screen has no halo when displaying, wide viewing angle, and uniform color, but the glue layer of GOB LED screen may cause slight light scattering
Cost: COB LED screen has a relatively complex process and high cost. GOB LED screen is based on SMD improvement and has relatively low cost.
Maintenance difficulty: COB LED screen needs to replace the entire module, and GOB LED screen has a glue layer, which will increase the difficulty of maintenance.
3. Application scenarios
COB LED screen: suitable for high-density, high-reliability scenarios, such as indoor conference rooms, medical displays, and high-end commercial advertisements.
GOB LED screen: suitable for outdoor or semi-outdoor environments (such as stages and stadiums), projects that require certain protection but have limited budgets.
4. Summary of advantages and disadvantages
Advantages of COB LED screen: high protection, high density, long life, suitable for the future Micro LED trend; disadvantage is high cost.
Advantages of GOB LED screen: high cost performance, significantly improved protection; disadvantage is that the display effect and heat dissipation are slightly inferior to COB.
5. Development trend
COB LED screen: As Mini/Micro LED technology matures, COB's share in the high-end LED screen market will gradually expand.
GOB LED screen: As a transitional solution for SMD, it still has a certain space in the mid- and low-end market, but it may gradually be replaced by COB.
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