The thermal path (60c) thermally connects the interior of the package to the external environment.

In the arrangement, the thermal coupling element is located to form a thermal path from the heat region of the first tier die to the heat sink.

Care must be taken to make sure that there is a good thermal path to the thermistor, and that thermal mass is as small as possible.

The thermal insulation produced is in fact a combination of insulation and thermal inertia achieved by multiple air holes and extending the thermal path crossing the wall.

Using the inventive dummy load, there is no thermal path back to the light emitting diode (LED) board.