Design Engineering Note: Micro-Fit 3.0 Power Header
The Molex 430451028 is a 10-circuit, dual-row, through-hole vertical header from the Micro-Fit 3.0 43045 series. It connects a board to a cable/wire harness, mating with the corresponding Micro-Fit 3.0 receptacle housing and crimp terminals. The 3.00mm pitch and 8A per circuit rating place it firmly in the power interconnect class — the 8A rating is the current limit per contact at the rated temperature rise, not a signal-level spec.
The 10 positions at 3.00mm pitch (0.118") match a standard 2-row footprint — the row spacing is also 3.00mm, so the PCB layout uses a 3mm grid. The gold mating contact finish at 15.0µin (0.38µm) supports moderate mating cycle counts and resists corrosion in humid or mildly corrosive environments — the tin solder tail (100.0µin) is standard for wave solder. The 600V voltage rating gives generous creepage margin for the 3mm pitch. The UL94 V-0 LCP housing handles the temperature rise from the 8A load without flame propagation.
This header mates with the Micro-Fit 3.0 receptacle housing (e.g., the 43025 series) loaded with the appropriate crimp terminals (e.g., 43030 for 20-24 AWG).