With the development of LED display technology, there are more and more new terms of LED displays emerging in the market.

This article will explain the difference of COB, GOB, SMD 4-in-1 LED displays.

1. 4-in-1 LED means the four group of RGB chips share the same solder plate. It is widely used for small pixel pitch LED displays with pixel pitch below 2mm.

For fine pitch LED displays, because the pixel pitch is too small, such as P0.9, by common SMD LED lamp with one group of RGB chips encapsulated in one LED, it can not meet the requirements of the gap. and if do it by common SMD type, the SMT machine efficiency will be very low. thats why 4-in-1 type LED lamp is invented.

Four groups of RGB chip encapsulated on one LED, and share the same soldering points, this way the soldering to the PCB is stronger. and the machine efficiency is 4 times higher. 

Below is a P0.9 SMD 4-in-1 LED module and LED lamp

2. COB LED: COB means "chip on board" which means the RGB LED chip is embedded on the PCB board. this technology is also invented by the needs of fine pitch LED displays. with this technology, it does not need the SMT machine process. The LED chip is directly encapsulated on the PCB board.

This technology the advantage is that  the contrast ratio of the LED display is very high, when turned off, the display surface is mostly black.

and with this technology, it can have good protection to the LED chips, anti-collision.

The disadvantage is that it is basically impossible for customers to repair it.

3.GOB LED display: GOB means "Glue on board" 

It is actually common SMD type LED modules with fully glued on the module surface.

This process does not use common masks, but directly glue on the LED module surface.

All the LED lamp are fully wrapped with glue, even the LED legs, solder points.

By the process, common modules can be well protected. anti-collision, anti-humidity.

Disadvantage is it is also hard for customers to repair, need to send to factory to repair.

The repair needs to dig the glue out first and then change or repair the LED and glue it back.

Below is a P1.875 GOB module surface

No matter COB, GOB, 4-in-1, such technologies are just a compromise for the stability and reliability of LED displays. None of them so far can reach the level of LCD panel malfunction level.

For instance even the COB can not ensure 100% without dead pixels.

but it leads a way for future LED display technologies.

Visualpower can provide all above LED display types according to the specific project requirements.