0.35mm Pitch, 0.6mm Stack — the BM28 Ultra-Compact Header
The Hirose BM28B0.6-34DP/2-0.35V(53) is a 34-position, 2-row header from the BM28 series, built for the tightest board-to-board stacking applications. Its defining dimension is the 0.014" (0.35mm) pitch — that's the spacing that decides your PCB routing density and the FPC/FFC pad pitch it mates with. The mated stack height of 0.6mm sets the z-budget for the entire enclosure; there's no adjustment, so the mating receptacle must match this exact height. The outer shroud contacts and solder retention features are what keep this seated during reflow and through the life of the product. Surface-mount termination with the shroud means the connector self-aligns on the pads — no through-hole anchors, so the solder joints take all the mechanical load. The solder retention feature adds a bit of extra hold to the outer corners, which matters when the board flexes in a thin device.
34 vs 36 Positions — the Nearest Sibling
The closest functional alternative is the 36-position BM28B0.6-36DP/2-0.35V(53) — same 0.014" (0.35mm) pitch, same 0.018" (0.46mm) height above board, same gold plating and solder retention. The only difference is two extra positions. That means the PCB footprint shifts by 0.70mm in length (two pitches at 0.35mm each), so a board laid out for 34 positions won't accept the 36-position part without a layout change. The 30-position BM28B0.6-30DP/2-0.35V(53) is the other direction — same footprint rules apply.
RoHS compliance is confirmed on record, so it passes the materials declaration for EU-market equipment.