Hi,
I have tried to think about different ways to easily align the PCB DUT into the test jig fixture. I will build the jig from various stacks of PCB's.
Lower PCB: Solder pogo pins.
Middle PCB1: Holes for pogo pins to keep them aligned and vertical.
Middle PCB2: Cutout which is slightly smaller than the DUT PCB which the DUT PCB will press against and rest on.
Upper PCB: Cutout for DUT PCB to keep it aligned.
The upper PCB could be a stack of 2 or 3 pcs of the same PCB. This way the DUT PCB can "fall" into the slot before it "meets" the test pogo pins.
Then it can be pressed further down onto the pogo pins until it meets the "Middle PCB2".
The DUT can be held down by a clamp (the normal ones used), or there could be
cutout slots in the absolute upper PCB(s) where some sliders (PCB material as well) could be used to keep the DUT PCB down.
These sliders will be gliding upon the lower "Upper PCB". These Upper PCBs could all be the same with removable mouse bite slots where the
sliders is to be positioned. Actually with some clever design, all Middle and Upper PCB's could be the same design with removable cutouts etc.
Another solution to the Upper PCB approach could be to use alignment pins. I have some concerns about this.
Due to friction and tight tolerance it could be cumbersome to press the PCB down when there are 4 alignment pins.
I have also trouble finding alignment pins which can be screwed onto the jig boards.
There are lots of dowel pins, but these must somehow be secured to the jig boards.
I thought of one solution: I could use 4 (or more) robust pogo pins with conical tip as alignment pins:
https://www.aliexpress.com/store/product/Free-Shipping-100pcs-lot-P156-B-33-85mm-spring-test-probes-pogo-pin/518673_1686189927.htmlThis tip is 2mm thick (thickest I could find). I could have 1.5mm holes on the DUT PCB. The conical tip would enter the holes when positioning the PCB,
then it can be pressed down until it meets the test point pogo pins. I would think that the conical tip will center align into the holes...
The tips themselves are actually a tiny bit wobbling. The solution for this is to let the tip itself enter the Middle PCB1.
Any tips, comments?