Board-Stacking Receptacle for Tight Z-Budget Designs
The Hirose DF40B-10DS-0.4V(51) is a 10-position receptacle from the DF40 series of board-to-board mezzanine connectors. It uses a 0.016" (0.40mm) pitch across two rows, with a mated stacking height of 1.5mm — the tightest vertical profile in the DF40 family. This makes it a fit for handheld or portable devices where board spacing is at a premium. The gold-plated center strip contacts are suited for signal-level current, and the solder retention feature keeps the part anchored during reflow.
What the 0.40mm Pitch and 1.5mm Stack Mean for Layout
The 0.016" (0.40mm) pitch sets a tight trace-and-space requirement on the PCB — expect 0.20mm lines and 0.20mm clearances between pads for a two-layer board. The 1.5mm mated stacking height means the opposing board sits 1.45mm above the receptacle's mounting surface, so the total z-height from the bottom board to the top board is the sum of both connector heights plus the air gap. Gold contact finish at 2.00µin (0.051µm) is a signal-grade plating; it handles the mating cycles typical of a battery or display interconnect without the cost of a thicker hard-gold layer.
Position Count and Series Variants
The DF40B-10DS-0.4V(51) carries 10 positions. For a different circuit count, the DF40B-12DS-0.4V(58) offers 12 positions at the same 0.016" (0.40mm) pitch and 1.5mm stacking height — the choice is strictly the number of signal lines needed. If shielding is required, the DF40GB(1.5)-10DS-0.4V(58) adds a metal shield over the same 10-position layout, though it changes the footprint slightly and must be paired with a shielded mating header.