Which led is better ? SMD or COB ?
COMPARISON OF SMD AND COB TWO LED PACKAGING TECHNOLOGY
SMD (patch) light source has a large luminous angle, up to 120-160 degrees, high assembly density, small size and light weight of electronic products. The volume and weight of patch components are only about 1/10 of those of traditional cartridge components. After SMT is generally used, the volume of electronic products is reduced by 40%-60% and the weight is reduced by 60%-80%. In addition, it has high reliability and strong anti-vibration ability. Solder joint defect rate is low; high frequency characteristic is good, reducing electromagnetic and radio frequency interference; it is also easy to realize automation, improve production efficiency, reduce costs by 30%-50%, save materials, energy, equipment, manpower, time and so on. A kind of
COB (integrated) packaging technology is one of the bare chip mounting technologies. LED chips are handed over and mounted on printed circuit boards. The electrical connection between the chips and the substrate is realized by lead stitching method and covered with resin to ensure reliability. COB light source module belongs to high power integrated light source. The circuit can be designed at will according to customer's requirements, and the heat dissipation is more reasonable. It can effectively avoid the shortcomings of spot light and glare existing in the combination of discrete light source devices. With less glare, the color rendering of the light source can be effectively improved by adding appropriate red chip combinations without significantly reducing the efficiency and lifetime of the light source. The angle of view is large and easy to adjust, which reduces the light refraction loss. The light output is more uniform and the installation is simple and convenient. A kind of
The comparison tables are as follows: Project_Traditional SMD Packaging_
Solid crystal, welding line efficiency and traditional SMD equivalent, post-site glue,
Separation, spectroscopy and packaging efficiency are higher than traditional SMD.
Thermal Resistance_Chip-Solid Crystal Adhesive-Solder Joint-Solder Paste-Copper Foil-Insulation
Layer-Aluminum Material (Thermal Resistance is Higher than COB Packaging)Chip-Solid Crystal Adhesive-Aluminum Material (Low Thermal Resistance)
Light quality Discrete device combination has spot and glare
Large angle of view and easy adjustment to reduce the loss of light refraction
Application of During the period of LED, it is necessary to fix the chip on the PCB board by reflow soldering.
COB light source is directly used in lamp without mounting and reflow process.
Upper and lower
Cost High Low
Comparing the advantages mentioned above, it can be seen that COB light source has five advantages over traditional SMD package light source. It has great advantages in light source production efficiency, thermal resistance, light quality, application and cost. The comprehensive cost can be reduced by about 25%, and the device is simple and convenient to use, and the process is simple. A kind of
From this we can see that SMD packaging gradually to COB transformation is the general trend! A kind of
LED Packaging Technology
1. Surface Mount Packaging (SMD). In 2002, surface mount packaging LED (SMD LED) was gradually accepted by the market and gained a certain market share. The shift from pin-type packaging to SMD conformed to the general trend of the development of the entire electronic industry. Many manufacturers launched such products.
2. COB Packaging (Integration)
COB package can directly encapsulate multiple chips in metal-based printed circuit board MCPCB. Direct heat dissipation through the substrate can not only reduce the manufacturing process and cost of the bracket, but also have the advantage of reducing heat resistance.