HPDC series chip resistors use an aluminium nitride (AlN) ceramic substrate which has about 6 times the thermal conductivity of alumina, which is the conventional substrate material for chip resistors. In addition they feature large area terminations for improved thermal contact with a PCB. As a result, heat generated in the resistor element is effectively conducted away, reducing the temperature rise.
Because of these features, HPDC resistors offer a high power density solution with ratings of 2.4W in 1206 and 3.5W in 2512 footprints. The short term overload performance is also enhanced, at 4.7W in 1206 and 7.7W in 2512 for 5 seconds, making them ideal in active capacitor bleed circuits.
These high power resistors may also be used in temperature controlled heating applications in which the power applied is restricted only by the maximum element temperature of 155°C and the maximum termination temperature of 110°C.