Chip-on-board, COB, is a technology where uncoated semiconductor elements (dice, die, chip) are mounted directly on a PCB or a substrate of e.g. glasfibre epoxy, typically FR4 and die bonded to pads of gold or aluminium. For the fact that in an IC the die itself is very small compared to its package, the COB-technology gives opportunity to leave away the package. In consequence board designs may be layouted more densely and at the end will be much smaller.