Board footprint and pinout for the 4-circuit MTA-156 header
The 640445-4 is a 4-position, single-row header on 3.96mm pitch — the board footprint is a straight line of four 0.125" (3.18mm) solder posts, through-hole mounted. The 0.400" (10.16mm) mating pin length engages fully with the MTA-156 receptacle before the friction lock snaps. The 600VAC rating covers 480V line-voltage control panels with margin. The single-wall shroud guides the receptacle onto the pins but leaves the top of the contact row exposed — this is a cost-reduced shroud design for applications where full enclosure isn't needed.
Mating half and assembly BOM
This header mates with the MTA-156 receptacle housing (e.g., TE 640550-4) and requires the matching crimp contacts — typically TE 350079-1 (tin, 18-24 AWG) or 350079-2 (tin, 26-30 AWG). Build-to-print needs both halves and the contacts — the header alone is only half the BOM.