What This Connector Does in the Harness
The TE Connectivity 3-643818-7 is a 7-position MTA-156 IDC receptacle designed for mass-terminating discrete or ribbon cable to a 0.156" (3.96mm) pitch header.
Pitch, Positions, and Termination — What Fits the BOM
The 0.156" (3.96mm) pitch is the defining board-layout dimension — it matches the standard MTA-156 header footprint. The IDC termination accepts 20 AWG wire only, so verify your wire gauge against the BOM before committing.
Mating and Mounting — Free-Hanging Receptacle
It mates with the corresponding MTA-156 header (male pin strip) that is through-hole or surface-mount soldered to the board. The closed end and polarizing key prevent incorrect insertion: the closed end blocks a header with more positions than 7, and the key ensures the receptacle can only be mated one way.