I've got a small smt board I've already got working prototypes of, which uses a tactile switch. I've got another much less expensive tact switch of similar size that I had avoided due to a difference in actuators I originally had no way around. Now I think I've got a way around that issue, and would like to design the board so it could be used with either switch if possible.
Both switches have four leads. There is overlap between the manufacturer-recommended pad layout for one switch and the manufacturer-recommended layout for the other switch, but it isn't exact. (One has the leads slightly further apart and a bit differently sized.) Also, one manufacturer recommends rectangular pads, the other recommends a squat T shaped pad. I've attached an image that shows the two separate footprints, and also shows them overlaid.
I've designed a number of prototype boards in the past, but am new to design for automated SMT production. So I thought I'd get some advice here about the advisability / likelihood of success of combining the two footprints. My thought was to make a composite pad the shape of the two pads overlaid, but have separate stencils, applying solder paste only for the particular switch being used in that run. We are likely to be having them assembled in runs of 1k-2k boards. The boards are double sided with SMT components on both side. The switch and a couple of 8-pin SOICs are the largest components.
This is for a consumer application in a very benign environment, so I'm not too worried about part of the pad (corresponding to the switch not being used) being exposed without soldermask.
Thoughts?
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