Board-stacking selection — what this header does
The Hirose DF12B(4.0)-30DP-0.5V(86) is a 30-position board-to-board header from the DF12 series, built for mezzanine stacking applications where board spacing is tight.
Footprint and board layout
At 0.50mm pitch, the footprint demands tight routing discipline — trace widths and via diameters must be kept small to fit between pads. The 0.130" height above board is the component standoff; the actual clearance between boards is the 4mm mated stack height, which includes the receptacle height. Plan the keep-out zone on both boards to avoid component interference under the stack.
The 4mm mated stack height is non-negotiable for the z-height: if the design calls for a different board spacing, this header will not work without changing the receptacle or adding a spacer. The solder retention features are a practical advantage on an SMT part: they reduce the chance of the header lifting off the pad during wave solder or under cable strain.