Right-Angle Board-to-Board Receptacle, 40 Positions
The Hirose FX2-40S-1.27DS(71) is a 40-position board-to-board receptacle from the FX2 series, terminated through-hole with a right-angle orientation. The 40 circuits in two rows give a dense but routable interconnect for parallel-board stacking where the receptacle sits on the bottom board and the header drops in from above. Gold contact finish at 7.87µin (0.200µm). Right-angle through-hole termination.
Mounting and Board Layout
The 1.27 mm pitch is the centreline spacing between adjacent contacts; the two rows are offset by half the pitch, so the footprint requires staggered through-holes. Board layout engineers need the Hirose recommended pad pattern to avoid routing conflicts between the two rows. The outer shroud contacts are the defining feature of this FX2 receptacle — the shroud surrounds the mating area and guides the header into alignment. This design protects the contacts from damage during blind mating in a stacked-board assembly, where the operator cannot see the interface.
It is ROHS3 compliant, which covers the full restricted-substance list for EU-market equipment. No official successor part has been assigned; the (71) suffix indicates a specific plating and packaging variant within the FX2 family.
The active lifecycle means the factory continues to produce the FX2-40S-1.27DS(71), so lead times are typical for a current-production Hirose connector.