Normally LED lighting product consist of 3 Parts: LED light source, LED power supply, Shell.
1.LED light source part:
LED light source include 3 main types:DIP, SMD, COB. The production procedure different for them.
—Dip is called dual inline-pin, which means it has 2 kinds of pins and 1 is cathode, the other one is anode. The cathode and anode is connected by the power supply so the LED can work. Picture as follow:
Dip LED is widely used on LED Screen, LED indicator light, some LED lighting product like LED PAR light, LED Corn light, LED tubes and so on. However, Dip LED is gradually abandoned due to its low light output and low heat-dissipation ability , many of them are replaced by SMD LED.
—SMD is called Surface Mounted Devices, which do not have Pin but contract electrode. The LED is powered through the electrode. Picture as follow:
SMD LED is more and more popular because of its good product efficiency and good heat-dissipation ability. Many of the SMD LED is low power LED, but high power LED SMD is increasing in the market, like LG 5630,5152, 3014. LED Candle bulb from No.1 lighting has some SMD version, like 5630 and 3014 version.
–COB is called chip on board, it is a new LED Packaging type of light source. The difference from SMD is: COB is the LED chip directly attached the metal plate, but SMD is stick to the surface. Picture of COB is like below:
COB is mostly used for high power LEDs, from 1W to 200W. No.1 Lighting’s COB LED Candle light used 1W LED chips. COB’s cost is higher than SMD due to its complicated production proess.