80-Position Mezzanine Plug at 0.80mm Pitch
The 0.031" (0.80mm) pitch packs 80 circuits into a dual-row layout, and the 0.201" (5.10mm) height above board sets the mated stack height — critical when you're budgeting z-space between mezzanine boards. This is a plug with center strip contacts, right-angle SMT mount, meant to mate with the matching Free Height receptacle on the opposing board.
Pitch, Position Count, and the Board Footprint
The 0.80mm pitch is the tightest in the Free Height series — compare it to the sibling 1-120532-2, which runs 84 positions at a wider 0.039" (1.00mm) pitch and a taller 0.250" (6.35mm) stack height. That extra pitch buys you more routing channels between pads, but the 316229-3's 0.80mm pitch is the right call when the board real estate is the constraint. Both are dual-row plugs, but the 316229-3 carries a board guide to keep the alignment during reflow — the 1-120532-2 substitutes a pick-and-place feature instead. The 316229-3's gold thickness is 11.8µin (0.30µm) versus the 50.0µin (1.27µm) on the 1-120532-2; the thicker gold on the sibling buys more mating cycles if your application cycles boards frequently, but for a typical mezzanine stack that mates once in production, the 316229-3's gold is adequate.
Board Layout and Assembly Considerations
The board guide is not cosmetic — it prevents the part from skewing during reflow, which matters when you have 80 solder joints at 0.80mm pitch. No press-fit or through-hole here; this is a reflow-only part, so your stencil aperture and paste volume need to match the fine-pitch footprint. The package is Tube, so plan for tube-fed pick-and-place or manual placement for prototypes.