We always have in our designs situations where one pin of a row of SMD discretes (mostly 0201's) is tied to a solid plane of copper with no thermals. Over the years, our fab houses flag this and have requested to adjust the mask opening on the plane connection to make it smaller so that it doesn't become a larger 'pad' than the other side of the discrete. We've had this done this successfully over the years. The question has arisen whether we could make this adjustment ourselves within Allegro so that the fab house doesn't have to do it. I can't think of a quick and easy way to do this. How does everyone else accomplish this? Thanks for any insight you can offer.
We have a very similar issue and on small parts such as 020s1 it can create an assembly issue since each side has a different metal exposure. Even just switching to a thermaled connection does not solve the metal exposure issue since the extra metal from the thermals bleeds off solder unevenly. I suspect these are caps since you want to reduce any possible extra inductance? If they were resistors that were pullups it makes sense to connect with a small trace and not direct connect to the plane. To deal with this we have an alternate part with soldermask defined pads. When placing you can right_mouse->alternate part assuming you set up the alternate footprint in OrCAD or Concept (DEHDL).
You can also do just an instance replace of the pad attached to the plane after initial layout is done. You would have to replace the pad with a soldermask defined pad. I find that a bit error prone.
Thank you all for your responses. In some cases, we can use thermals. In others, we cannot because too much of the plane would be diminished (some of these planes are powers, not GND). The option of alternate footprints with soldermask defined pads is probably the best. Thanks again.