Is the lack of fine-pitch probes and fixtures preventing product advancement? That’s the thinking of developers at AlphaTest Corp. With the drive toward product miniaturization, many electronic assemblies have small testing targets on close center-to-center spacing that cannot be contacted by traditional test probes. Thus, electronics manufacturers must locate fine-pitch test probes or risk not being able to advance product functions because of the inability to miniaturize; or because they must omit some test procedures; or scrap a product update.
A new generation of fine-pitch test-probes can probe these electrical targets with ±15 µm pointing accuracy on 10 mil center-to-center placement. AlphaTest has a range of such fine-pitch test probes under the µHELIX® Test Probe brand name in diameters of 20, 16, 12 and 8 mils. These include fine-pitch spring-loaded test probes that can meet the mechanical challenges of testing miniature circuits such as hybrids, RFID antennas, flex-circuits, flat panels and many of the following package types: StripLine, BGA, CSP, SoC, SiP, MEMS, mcm, photonic devices.
In medical electronics, St. Jude Medical, Inc., Scottsdale, Ariz., incorporates fine-probe testing of miniature implant products that it designs and manufactures for critical heart-related devices such as electronic pacemakers and defibrillation leads. All of these products must comply with standards as well as low physiological implant complication requirements.
“To test these medical devices, the fine-pitch probes are installed in electromechanical test fixtures,” says David Montgomery, St. Jude Medical Production Engineering Manager. “The fixtures include these probes (normally 20 mil or smaller), a guide plate, and a latching mechanism.”
Montgomery explains that the “package” for the electronics must be small and ergonomic to remain in the human body. And for that reason it is difficult to use an off-the-shelf test probe fixture.