LED
Packaging
The LED
chip is mounted
in a housing which provides mechanical stability, electrical
connections, and
focuses the light. It also dissipates the heat generated in the chip.
This housing is called packaging.
There are
different
ways of packaging an LED chip:
1. 5mm-LED
The
chip is glued into a small pan connected to the - lead, a bonding wire
connects
to the + lead. The complete assembly is molded into a transparent
plastic which
holds the leads in place.
Since the heat is transferred via the - lead,
only, this
packaging is only suitable for low power LEDs.
For lighting LEDs it would operate near the thermal limits of the chip.
The
first generation of LED lights used this packaging - resulting in low
lifetime
