Looks like I’m going to need to create my own 44-pin PC edge connector (22 pins each side, 0.156 centers) since I don’t find one anywhere.
I’m curious how to specify chamfering the edge. Is this specified in the fab drawing? If so, how?
You draw a comment on one of user layers and notify your pcb fab that you want a chamfer.
Kicad doesn’t have any way to specify chamfer in it’s data model, I’m not sure if gerbers support it at all.
You could do it in the PCB outline. Define the pad pattern for the connector and place it. Bit of a kludge, but should work.
A bit curious here: remember those from old SBCs (KIM-1, SYM-1). Am I on track?
I’m pretty sure OP is not talking about chamfered pads but about chamfered pcb edge.
That’s what I meant, but perhaps phrased it unclearly. Where did I mention “chamfered pads”? I distinctly said “PCB outline”.
I’m not sure what that means then. Or how that helps achieve chamfered pcb edge.
Given that I have a US Patent on Connector for Edge-Card PCB (for Medical device) I can say from many experiences (though, not from China) the Chamfer MUST be noted on a Drawing for the fab-house to read and be held accountable for errors and cost.
Best to also add note to a Purchase Order
Snippet of Connector Abstract (from patent) FYI. Every engineer that designs an EdgeCard PCB knows to use Chamfer and notate it. Sure, there are many EdgeCard PCB’s without it and many don’t need it IF the design dictates it… If using a Connector for which you know very little about, look up it’s interface reqmt…
If you mean the longtitudal chamfer, it’s unnecesary for an edge connector of the type the OP mentioned. The only chamfer needed is the one on the corners, which is done with the PCB outline.
But I understand the discussion now, we’ve been talking about two different things.
I usually look to see if the mating connector manufacturer has a recommended requirement for the mating PCB and more or less copy that onto my fab print.
For example, from the Samtec HSEC8 connector print:
I recently did some 0.156" edge connectors on boards ordered from AllPCB. They did the chamfering without my even asking, all I had to do was check the “Golden Fingers” box in the online quote.
You really should contact your PCB vendor for how they want the chamfer (to make inserting into an edge connector easier) annotated. Also if you want the finger contacts to be hard-gold plated (different process and end result from ENIG) find out if they want anything special. I remember in the dark ages the PCB vendor my company used (I forget the vendor’s name) wanted the fingers to be shorted together because they used an electroplate method to deposit the gold. This short would then be removed when the chamfer was cut. Your vendor might request something similar, or might not.
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