The development history of LED displays has been more than ten years. The current common LED display screens are, according to industry standards, mainly divided into DIP LED display screens and SMD LED display screens. The LED display screen is formed by stitching LED modules one by one.
Whether it is DIP or SMD, it is ultimately spliced into a surface to display the playback content. In terms of structure, each LED module is composed of a light surface, a PCB circuit board, an IC surface, and a bottom shell mask.
So what's the difference between a DIP LED display and SMD LED display? The author makes a comparison from the following three aspects.
1, Raw materials
The first is the difference between lamp beads. The LED beads used for DIP LED display screens are mainly irregular long round lamp beads. The main models are f3 / f5 / 346 and other models. The packaging technology is mature, the waterproof performance is good, and the light-emitting surface is a full light-emitting surface.
SMD LED lamp beads are mainly in the shape of a cube or a rectangular parallelepiped. The packaging process is to fill the chip into a metal bracket and then dry it with glue. The specifications are 3535/3528/2835/2727 (2525) / 2121/1921(1820) / 1515/1010 and many other types, its packaging technology has matured, the light-emitting surface is single front light.
2, PCB circuit boards
The second is the difference between PCB circuit boards. The PCB circuit board used for the surface-mounted LED display is a padded surface, which is used to solder the lamp pins of the surface-mounted LED lamp beads. The PCB circuit board used for the in-line LED module is vacant at the relevant pad position and is reserved for the in-line LED lamp beads to be soldered.
Finally, the simple cattle power socket used by some DIP LED modules is different from the SMD modules and is also DIP instead of surface-mount.
Second, In terms of the production process, the production process of the DIP LED display module is: printing IC surface solder paste on the PCB → SMD IC → temperature-reflow soldering through reflow soldering → inserting DIP LED lamp beads into the corresponding PCB board Hole position → Spraying tin → Reflow soldering for heating the lamp surface → Power socket and simple post-solder welding process → Testing and aging maintenance → Outdoor LED module is spray-proofed and paint-proof (for indoor LED modules, this can be omitted) Step) → Put on the bottom case mask lock screw → testing and aging → packing and shipping.
The production process of SMD LED display module is: printing IC surface solder paste on PCB → SMD IC (including simple cow and power socket) → temperature reflow soldering through reflow soldering → printing lamp surface solder paste on PCB → table Paste LED lamp beads → Over-reflow soldering to heat-up the lamp surface → test aging maintenance → outdoor LED modules are spray-proofed and glued (for indoor LED modules, this step can be omitted) → put the bottom case mask lock screw → Test aging → Shipping.
From a technical point of view, the production process of SMD LED display modules is simpler than DIP LED display modules.
3, Application and usage
Due to the limitation of its structure, the DIP LED lamp beads are mainly used in P10, P16, P20, and other pitches. The smaller pitch is P8, and the minimum pitch is P6. Because of its good waterproof performance, it is mainly used in outdoor products.
The SMD LED lamp beads can be adjusted due to their structural rules, and the metal bracket can be adjusted. There are various types. Indoor P10 / P7.62 / P6 / P5 / P4.75 / P4 / P3 / P2.5 / P2 / P1.875 / P1.667 / P1.56 / P1.25 / P1.0 and so on. Various pitch applications are available.
4, Performance of the display
The first is brightness comparison. For products with the same pitch, such as DIP P10 outdoor full-color LED display and SMD P10 outdoor full-color LED display, the brightness of DIP is generally greater than that of SMD.
The second is the appearance comparison. As mentioned earlier, the DIP lamp beads are long and round, and the display surface is originally uneven, and its light is multi-faceted. Therefore, in terms of appearance, the surface of the DIP LED display is not as flat as the SMD LED display Smooth. The effect of lighting, at a close distance, is not as smooth and supple as the display effect of the surface display.
The last is a comparison of service life. DIP lamp beads are generally larger than SMD lamp beads, and the sealing of the package is more complete and unified than SMD lamp beads (DIP lamp beads have a uniform arc surface, and SMD lamp beads are a cube with 6 sides) ), From the perspective of actual performance, DIP LED display is brighter than SMD LED display and has a longer service life. Of course, in the same pitch applications, DIP LED display is also much more expensive than SMD LED display. On the contrary, the application of SMD LED display screens is becoming more and more widespread, and the market share is increasing. It is also related to the application of more space requirements and the continued decline in prices.
The above is a comprehensive summary of the differences between the DIP LED display and the SMD LED display.