Right-Angle 78-Position High-Density D-Sub with Board Locks
The TE Connectivity 2311772-1 is a 78-position, 4-row D-Sub receptacle from the AMPLIMITE HD-22 series, configured for right-angle through-hole mounting. This is a high-density shell layout (DD, D) — the 78 contacts pack into a shell size that would normally carry 44 positions in a standard-density D-sub.
For signal-level currents, this rating provides ample headroom, but if you are pushing near the limit across all positions simultaneously, derate per the temperature rise curve in the product drawing.
The 0.350" (8.89 mm) backset spacing sets the distance from the PCB edge to the mounting flange face, which determines how far the connector overhangs the board edge. The flange uses the standard D-sub 4-40 threaded insert pattern, accepting jackscrews from the mating plug. The steel shell is nickel-plated for EMI shielding continuity when mated.