In SMD (Surface Mount Device) technology, beads are soldered onto the PCB whereas the COB process involves covering the silicon placement point with thermally conductive epoxy resin on the surface of the substrate. And the LCD chip is fixed to the interconnected substrate using conductive or non-conductive adhesive via adhesive or solder. Because of this chip establishes electrical co... https://www.campuscomponent.com/blogs/post/difference-between-cob-and-cog-lcd-technology