Smiths Connectors is now Smiths Interconnect


The Lowest and Most Consistent Resistance Since Probes Began

One of the most celebrated award winning probe designs ever introduced, the ICT Probe Series has completely revolutionized in-circuit testing. The ICT probe was not just another new probe design, but a design that marked a major change in probe construction. As test engineers witnessed the lowest and most consistent resistance and the most accurate pointing accuracy they had ever measured on test probes, the outdated bias designs gave way to the ICT Probe Series. While other probe companies continue to focus on the out-dated bias designs introduced over 30 years ago, IDI continues to enhance our revolutionary probe designs, making advancements that set new industry standards.

The ICT Series is so unique, you can actually feel the difference for yourself. Our probes have a distinct feel when compressed. Compress one between your fingers. The friction you sense during deflection of the probe is normal and expected. It is your assurance that the probe is indeed providing the pointing accuracy and consistently low resistance we promise.

The End of The Bias

In the past, probe designs have relied on biasing techniques to ensure positive electrical contact between the plunger and the barrel. In essence, the plunger of the probe is forced to an angle inside the barrel to provide two solid contact points for current transfer. The clearance between the plunger and barrel is typically .002 in this type of design. While seemingly small, this clearance is an avenue for contamination to enter the internal portion of the probe, blocking or severely affecting the current transfer. Another consideration of a bias design is the effect on pointing accuracy. In a bias design, the plunger is forced to an angle inside the barrel, forcing the probe to its worst case pointing accuracy to ensure positive electrical contact.

The ICT Series probes are not biased. There is no clearance between the plunger and barrel. These probes use proven pin and socket connector technology to ensure positive electrical contact between the plunger and barrel. The top of the barrel is machined and coined to form four bifurcated beams. These beams provide a compliant fit between the plunger and barrel, absorbing manufacturing tolerances, gently wiping the plunger shaft on every deflection, and forcing the plunger to perfect center. This guarantees every plunger is in contact with every barrel 100% of the time without biasing. The result is the lowest and most consistent resistance of any probe on the market. Additionally, the elimination of the clearance between the plunger and the barrel virtually seals the internal portion of the probes from contaminants and provides the absolute best pointing accuracy.

New Plunger Packs More Power

The ICT Series features an improved plunger design and a corresponding new beam design. These new design enhancements make the ICT probe so strong, the barrel of the probe will bend before the beams will deform. During the manufacturing process, the bifurcated beams are customized for each plunger, eliminating any manufacturing tolerance between the plunger outside diameter and the inside diameter of the beams. 

The new plunger design has a reduction in the retained length of the plunger by .100. In a bias design, the shortening of the retained plunger length has a dramatic negative effect on pointing accuracy. However, since the ICT design perfectly aligns the plunger to the barrel, the shortening of the retained length of the plunger has minimal effect on pointing accuracy. This design also enables higher spring forces with longer spring volume. By increasing the area for the spring (length of the spring) while all other factors remain equal, the spring stress ratio is reduced allowing higher spring forces while eliminating tendencies for premature mechanical failure, specifically when over stroking occurs.

Proprietary Materials Lengthen Probe Life

The ICT Series also features the latest advances in materials and platings. Advancement in heat treating makes our steel plungers harder than before, while retaining their elastic properties. The ICT probes also feature our new G2 proprietary barrel material and plating. Our G2 Barrel has a “less slick” fit between the barrel and receptacle to minimize any tendencies for probe “walk out.” 

Unique Receptacles Reduce Walk Out

To further reduce probe walk out, IDI receptacles also feature four detents as compared to single detent designs.