PCB Manufacturing for Raspberry Pi HATs: DFM and Fit Guide

This is a use case manufacturing profile for Raspberry Pi HAT. The board profile below is a starting point to confirm against an exact fabricator quote, not a guaranteed price or capability.

Capabilities, prices, lead times, approved materials, assembly stock, shipping, and taxes change. Requote the exact revision and retain the supplier's order-specific confirmation before release.

• Freeze Pi model compatibility, official outline and mounting, header side, keepouts, ID EEPROM, 3.3/5 V use, current, back-power behavior, and stacking height.
• Freeze connectors, board outline, mounting, height zones, power budget, and environmental assumptions before treating the stackup as final.

Use one mechanical datum for header and holes, keep components out of Pi/enclosure zones, and route buses with appropriate pulls and voltage levels.

• Apply one named fabricator capability profile to traces, clearances, drills, annular rings, edge setback, mask dams, and panel rules; nominal defaults are not a quote.

• Fixture the long header square and at correct side/height, verify pin one, EEPROM population, and any tall or bottom-side parts.
• Give every fitted reference an exact MPN and footprint, keep BOM and placement reference sets identical, and inspect the assembler's rotation preview before release.

Validation plan:

• Fit approved Pi models and cases, verify EEPROM identification, power sequencing/back-power, every interface, thermal clearance, and stacking hardware.
• Bring up first articles on a current-limited supply, record rail and interface measurements, and test the physical loads, cables, enclosure, and environment the board was designed for.

Cost drivers:

• Long header, board area, stacking hardware, enclosure variants, manual through-hole assembly, and multi-model fit testing dominate.
• Area, layer count, panel utilization, drill count, finish, controlled processes, component variety, setup, and test time usually matter more than a headline per-board price.

• A 40-pin grid can be electrically correct while shifted relative to mounting holes or reversed to the wrong board side.
• A clean fabrication check proves encoded geometry, not circuit function, thermal margin, EMC, regulatory compliance, or mechanical fit.

Ask the fabricator directly:

• What fixture controls 40-pin header side, height, squareness, and pin-one orientation?
• Which Pi models, cases, and stacking spacers are included in mechanical acceptance?

1. S1Schematic/PCB parity and unresolved connectivity. Run ERC, DRC with schematic parity, and netlist comparison for the Raspberry Pi HAT release; explain every exclusion rather than suppressing it globally.
2. S2Quoted fabrication-profile compliance. Compare saved copper, holes, mask, outline, and 40-pin header, hat outline/holes, component keepouts, id eeprom, and stacking fit constraints with the exact quoted stackup and option set.
3. S1BOM, placement, polarity, and output identity. Require exact MPNs, matched BOM/CPL reference sets, reviewed rotations, one clean outline, and fabrication outputs regenerated from the approved Raspberry Pi HAT source revision.