M20-9990346 vertical header

Harwin 3-position single-row 2.54 mm header, 0.64 mm square pins, 3 mm PCB tails and 6.1 mm mating pin height. The 46 suffix is tin over nickel. It is unpolarized and has no intrinsic signal assignment or keyed mating direction.

The manufacturer specifies a 3 A maximum contact rating and −40 to +105 °C range. The drawing lists 50 mating operations for tin, versus 300 for gold. This is not a high-cycle workcell connector; assess expected service cycles and retention before product release.

Circuit and mating

The library numbers contacts 1 through 3 in a row from the footprint origin. This numbering is an Adom circuit convention for a geometrically symmetric header, not a claimed physical molded pin-1 identifier. In the custom electronic load, J9 uses 1 5V_AUX, 2 GND, 3 FAN_TACH. Inspect board silkscreen, harness continuity and connector orientation before connecting it.

The nominal harness study uses housing M20-1060300 with 3 M20-1180046 crimp contacts. That is an Adom-added termination; the Sunon fan itself has flying leads. Mating, contact insertion, wire gauge, stripping, crimp tooling, retention and polarity remain separate qualification tasks. The housing is not included with this bare header.

Library and geometry

The footprint follows 2.54 mm pitch and Harwin's recommended 1.02 ±0.05 mm finished hole. Its 1.7 mm copper pads and courtyard are Adom candidate geometry. Confirm plated-hole tolerance, annular ring, copper clearance and solder process with the fabrication service. A nominal drill field does not certify the finished hole.

The original nominal model is 7.62 × 2.54 mm in plan, 8.64 mm above the PCB and 3 mm below. It uses plain rectangular housing and flat pin tips: molded recesses, chamfers and tolerance envelopes are not fully reproduced. This is not Harwin CAD. STEP units are mm, GLB meters, Z up, body seating at zero, pin 1 at X=Y=0. The hero adds nonphysical footprint labels; board-use geometry omits them.

Manufacturer product page · Manufacturer drawing

Harwin links TraceParts CAD downloads requiring a registered email and Supplyframe assets. Those were not redistributed; their reuse rights were not established. The shipped model is Adom's original nominal reconstruction. See provenance.json and THIRD_PARTY.md.