Cob is a new technology of LED packaging for LED light engine.
COB lighting, single LED chips are placed directly on a circuit board (or substrate) which has thermal properties to disperse heat. Heat dissipation is a very important aspect of LED lighting because it can have a major impact on the life expectancy of the luminaire. Traditional LED chips are not placed directly on the substrate and therefore there is greater thermal resistance. As a result of improved heat dissipation, COB lights can have a higher LED chip density and therefore achieve higher light levels while maintaining or improving life expectancy. COB downlights and spotlights are characterised by the yellow chip (package) visible inside the reflector. Sometimes a diffuser or cover is placed on the light to hide the COB chip.
COB LED is less thermal resistance Among different LED components such as high power LED, SMD, dip etc, COB LED is best in less thermal resistance and cooling.