Board-Stacking Interconnect for Dense Signal Buses
The Hirose BM28B0.6-40DS/2-0.35V(53) is a 40-position receptacle from the BM28 series, designed as a center strip contact connector for board-to-board mezzanine stacking. It carries a 0.014" (0.35mm) pitch across two rows, with a mated stacking height of 0.6mm — the tightest z-budget in the series, sized for ultra-thin portable devices and compact module interconnects where every tenth of a millimeter matters. The gold-plated contacts (1.97µin finish) and solder retention features make this a production-grade SMT part for high-density signal routing, not a field-serviceable power interconnect.
What the 0.35mm Pitch and 0.6mm Stack Height Mean for Layout
The 0.014" (0.35mm) pitch is the dominant routing constraint — trace widths and via keep-outs on the board must be designed for this density, and the 0.024" (0.61mm) height above board means the connector sits flush against the PCB surface, leaving almost no clearance for passives underneath. The 0.6mm mated stacking height is the fixed z-axis dimension: the opposing board must be spaced exactly 0.6mm from the main board, with no adjustability.