SMD (Surface Mounted Device) / COB (Chip On Board)
Wired LEDs are becoming less common in favour of surface mounted devices (SMD). SMD LEDs are directly soldered onto a printed circuit board (PCB). This provides significantly better heat dissipation as well as the possibility of denser packing on the board. This way, a higher light intensity and homogeneity can be achieved. Another development is the chip-on-board technology where different light emitting chips (dice) are densely bonded on the LED pad, so that the fill factor of the LED (i.e. the ratio between luminous area and total area) is increased. These modules reach the highest light intensity, but such multi-chip LEDs also require more effort to dissipate the heat.