The Hirose DF9-19P-1V(69) is a 19-position, dual-row header from the DF9 series, featuring center strip contacts on a tight 0.039" (1.00mm) pitch. It's a surface-mount mezzanine connector designed for parallel board stacking, with a specified mated stack height of 4.3mm.
The 0.039" (1.00mm) pitch is the primary constraint for your PCB footprint. It's finer than a standard 0.100" header, so you're routing traces between pads on a tight grid — expect to use a 0.2mm trace/space design rule to escape the connector. The dual-row layout with 19 positions means the footprint is compact, but the routing density under the connector is what you'll need to verify against your layer stack-up.
Mated stack height and board spacing
The connector sits 0.130" (3.30mm) above the board and mates to a corresponding receptacle to achieve a 4.3mm stack height between parallel PCBs. That 4.3mm is your z-height budget — check that your enclosure, adjacent components, and any top-side shielding leave enough clearance. The board guide features help align the two boards during assembly, taking shear load off the fine-pitch contacts.
Contact finish and duty cycle
The DF9-31P-1V(69) is the same connector in all respects — same 0.039" (1.00mm) pitch, same 0.130" (3.30mm) height above board, same gold 8.00µin contact finish — except it carries 31 positions instead of 19. The choice between them is purely a circuit-count decision: match the number of signals your BOM requires. If you need 19 circuits, this is the one; if you need 31, the DF9-31P-1V(69) is the direct sibling.