Board-to-Board Mezzanine Header, 0.50mm Pitch
The Hirose DF12NB(4.0)-30DP-0.5V(51) is a 30-position header with outer shroud contacts from the DF12 series, designed for parallel board stacking at a mated height of 4mm.
The 4mm mated stacking height is the critical dimension for this part — it sets the card-to-card gap in a mezzanine pair. The header itself stands 0.130" (3.30mm) above the board surface before mating. With the matching receptacle (DF12NB series, 4mm stack height variant), the total gap between PCBs lands at exactly 4mm. The 0.50mm pitch forces tight routing — expect micro-vias or laser-drilled vias in the breakout region.
This 30-position header sits between the 20-position and 50-position options in the same 4mm stack height variant. The 30-position option matches common data bus widths and GPIO banks on microcontrollers without wasting board area on unused pins.
SMT Assembly and Solder Retention
Surface mount with integrated solder retention features — the header has small metal tabs that reflow to the board pads, holding it in place during wave or selective solder processes. No secondary adhesive or mechanical fastener is needed for typical reflow profiles. RoHS compliant per the listing, so no special handling for lead-free assembly lines.