™ Test Probesfor testing at 175ºC
The reason is the plating. The standard plating on a test probe is gold-over-nickel. When this kind of probe is used at temperatures above 150ºC, the nickel plating under the gold diffuses outward into the gold layer, and ultimately reaches the outside surface of the sliding contacts in the probe. When exposed to air, the nickel starts to oxidize and the performance of the test probe starts to deteriorate.
How bad does it deteriorate? A typical test probe with two sliding plungers used in a 0.5mm pitch socket will degrade from 50 milliohms average CRES when testing at room temperature, to 320 milliohms average CRES when testing at 175ºC. That’s bad!
HOT PIN™ test probes really improve the situation. Depending on the barrel material selected, the same 0.5mm pitch pin when modified to become a HOT PIN™ will operate at 175ºC with good durability and an average CRES of about 80 milliohms.
HOT PIN™ test probes have a proprietary boundary layer of palladium cobalt between the gold and the nickel. The PdCo layer acts as a barrier to stop the nickel from diffusing into the gold and forming oxides on the contact surfaces. And it forms a noble foundation to the gold that enhances the overall durability.
HOT PIN™ use pre-clad or e-barrel™ electroformed barrels to stop oxide formations on the barrel ID.
It’s definitely a cool way to do some hot testing.
