High-Density Mezzanine Receptacle at 0.40mm Pitch
The Hirose DF40C(2.0)-12DS-0.4V(58) is a 12-position receptacle from the DF40 series, built for board-to-board mezzanine stacking at a tight 0.40mm pitch. Gold-plated center strip contacts in a dual-row layout give it the corrosion resistance and cycle life needed for internal signal interconnects in compact electronics — think smartphones, tablets, or portable instruments where PCB real estate is scarce.
What the 0.40mm Pitch and 2mm Stack Height Mean for Layout
The 0.40mm pitch is the dominant constraint on the PCB footprint — it forces finer trace routing between pads and tighter keep-out zones around the connector body. At this pitch, the land pattern is small enough that an assembler needs good solder-paste registration; the SMD tails are close together. The 2mm mated stacking height is a fixed z-height: the mating header must also be from the DF40 series with the same (2.0) suffix to achieve that exact gap. A 12-position count means this receptacle serves a 12-signal bus; if your BOM calls for 24 lines, the DF40C(2.0)-24DS-0.4V(58) shares the same pitch and stack height but doubles the circuit count.
Mating Half and Sibling Comparison
This receptacle mates with a DF40 series header of the same (2.0) stacking height suffix — the header part number will carry a similar DF40C(2.0) or DF40B(2.0) base code with the matching 12 positions. The DF40B(2.0)-12DS-0.4V(58) is a direct sibling with the same pitch, positions, and stack height, but adds solder retention features — a detail to check if your board assembly sees vibration or reflow shear forces. The DF40C(2.0)-24DS-0.4V(58) is the 24-position variant for a wider signal bus, otherwise identical in pitch and height.