Double-sided automatic test equipment probe clamshell with vacuum-actuated bottom probe contacts and mechanical-actuated top probe contacts

A two-sided probe and clamshell fixture embodiment of the present invention comprises a vacuum-actuated bed-of-nails for probing the bottom side of a printed circuit board (PCB) device-under-test (DUT) and a pushrod-actuated bed-of-nails for probing the top side of the printed circuit board device-under-test. The fixture comprises a base, a bottom frame, and a bottom plate that are sealed for vacuum actuation by a gasket. When in place, the DUT completes the vacuum seal and the bottom bed-of-nails which includes a patterned array of spring loaded probe pins reaches through the bottom plate to contact probe points on the DUT. A set of push rods attached to the base push out through the bottom frame and operate a set of gear boxes attached to the outer edges of a top plate within a top frame. A patterned array of spring-loaded probe pins reaches through the top plate to contact probe points on the topside of DUT when a vacuum applied to the bottom assembly causes the pushrods to advance and operate the gear boxes. The gear boxes reverse the direction of force received to cause the topside pushrod-actuated bed-of-nails to engage the DUT.