Page 10 - october22_previewaa.indd

TAP TIMES -10- OCTOBER 2022

High-power socket design (from 8) will melt. Great care must be taken in the
test program, sense feedback loop and
The heat transfer and convection cooling in test cell operation to prevent over current
this area is poor, so there is little external conditions lasting more than 50ms.
relief for the current/temperature function.
Probe lifetime
More robust materials The lifetime of the probes under high-cur-
Increasing the contact surface area, lower- rent loads also diminishes as the contact
ing contact resistance, and adding more resistance increases.
robust materials for the probe tip are the
main ways to address the issue. With high temperature (usually >250°C)
at the tips of the probe, tin migrates to the
The expectation though is that the mate- surface of the probes. Aggressive abrasive
rial and the operation of the probe will be cleaning can reduce the eff ects of the tin
degraded if high currents are regularly migration but adds to the tip wear
driven through the probe. and smooths the asperities needed to

make good contact.
In some conditions, the probe may be
destroyed as well as the surrounding PC Increasing the contact force of the com-
board and socket plastic material, which next page

High Connection Density, Inc.

542 Gibraltar Dr., Milpitas, CA 95035 Phone: 408/739-9700
www.hcdcorp.com - sales@hcdcorp.com
ISO:9001:2015