1. Packaging method:
1) SMD packaging through the SMD form of multiple discrete devices pasted on the PCB board to form the LED application light source components, such practices exist point light, glare and ghosting problems.
2) COB refers to Chip-On-Board, the low power chip directly packaged on the aluminum substrate for fast heat dissipation, small chip area, high heat dissipation efficiency, low drive current. Thus has a low thermal resistance, high thermal conductivity of high heat dissipation.
Compared with ordinary SMD small power light source features: higher brightness, small thermal resistance (<6℃/W), smaller light decay, higher apparent finger, perfect light spot, long life.
2. Production process :
1) The system thermal resistance of traditional SMD package application is: chip – solid crystal adhesive – solder joint – solder paste – copper foil – insulation layer – aluminum.
2) The system thermal resistance of COB package is: chip – solid crystal adhesive – aluminum.
COB package in the production process and the traditional SMD production process is basically the same, in the solid crystal, welding line process and SMD package efficiency is basically equivalent, but in the dispensing, separation, spectroscopy, packaging, COB package efficiency is much higher than SMD products.
Traditional SMD package labor and manufacturing costs account for roughly 15% of the cost of materials, COB package labor and manufacturing costs account for roughly 10% of the cost of materials, using COB package, labor and manufacturing costs can save 5%.
COB package system thermal resistance is much lower than that of traditional SMD package system thermal resistance, so it can significantly improve the lifetime of LED.