0.40mm Pitch, 0.8mm Stack — Mezzanine Header for Tight Z-Budgets
The Hirose BM20B(0.8)-30DP-0.4V(51) is a 30-position header from the BM20 series, designed for board-to-board mezzanine stacking where the z-height is tight. The 0.016" (0.40mm) pitch and 0.8mm mated stacking height place this connector in the ultra-fine-pitch, low-profile class — it fits between stacked PCBs with minimal clearance, common in compact handheld devices, camera modules, and portable electronics where every tenth of a millimeter counts. The 2.00µin (0.051µm) gold finish is a light flash — adequate for the few mating cycles typical of a factory-installed mezzanine connection, but not designed for repeated field disconnect. The contact finish thickness is the limiting factor for cycle life, not the contact beam itself. For a surface-mount part at 0.40mm pitch, the retention anchors are what keep the solder joints intact through thermal cycling and vibration in the end assembly.
The Tape & Reel packaging suits automated pick-and-place lines; Cut Tape options are available for prototype or low-volume runs.