Fixture mechanics is an essential part of the in-circuit (ICT) or functional (FCT) testing of an integrated circuit board or an electronic device. Some input of forces is needed to facilitate the generation of signal inputs and outputs in order to verify the operational state of a unit during or after manufacturing.
Reliable and repeatable mechanical actuation is critical in any application that isn’t a one off event (e.g. using a stick to move a rock – it’s probably not a concern if the stick breaks as long as the rock is moved). If electronic devices could be tested with a stick, there wouldn’t be any concerns with questionable reliability because there would be an essentially unlimited supply of replacements available (unless you happen to be testing in the middle of some forsaken treeless environment like the Mohave desert!). Test fixtures are mechanical systems, some fairly simple and some quite complex, but they all require some level of mechanical actuation in order to connect and communicate with the device under test (DUT). The mechanics of the fixture are a critical component of a test system; without a reliable and repeatable actuator, the system is no better than a broken stick with no readily available replacement and may only be as functionally useful as a “boat anchor” if it is not generating test result data that is useful in validating the product and the processes that are used to produce it.
In-circuit and functional test fixtures vary widely in scale and complexity. Some are bound by the features and rules of the base platforms they are to be used on, and thus often become a matter of fitting 20 pounds of %*)@! in a 10 pound bag. Others are unique stand alone fixtures or systems that are more “design from scratch” projects and not strictly bound by any parameters or rules of an existing base platform. The design process is often a mixture of developing unique solutions to mechanical challenges and of more mundane tasks such as placing board supports and selecting probe styles. All the tasks are critical to the overall function and reliability of the system, so the challenge is often to maintain a high level of detailed concentration when completing all the tasks to ensure a robust and reliable product.
The mechanical engineering design team at Circuit Check consists of 20 engineers that have nearly a combined 350 years of service designing fixtures and test systems. This experience is a crucial element in designing fixtures that are reliable runners that pose as little risk as possible to the device under test, and in training and developing new engineers as Circuit Check continues to grow and to expand into new markets and technologies.