Until now, Ohmite’s family of axial leaded current sense resistors had power ratings which are limited by the maximum temperature which the epoxy molding compound can tolerate. The new addition however, has a high purity alumina shell, filled with alumina powder, and then sealed with a high temperature compound. Inside is the same non-inductive, 3-piece metal element as the 10 Series, but since alumina ceramic can withstand much higher temperatures than semiconductor grade moulding compounds, this resistor can be safely rated at 4 watts in an 18mm x 6.4mm package, compared with the 3 watt component in this family which is 14.5mm x 5.2mm and the 5 watt type which is 23.8mm x 8.4mm.
The process to manufacture these items lends itself to mass production, since no moulding press with long cycle times and limited capacity for body cavities is required. Nine standard resistance values are available, all at 1% tolerance.