Arduino Sensor Interface PCB
Design a protected Arduino-compatible sensor interface from schematic review through assembly bring-up.
EDA workflow: KiCad 7+ or compatible EDADesign requirements
- 5 V input with reverse-polarity protectionn3.3 V sensor logic must use safe level conversionnI²C, UART and two protected GPIO connectorsnTest points for supply, ground, SDA, SCL, TX and RX
Required deliverables
- Schematic PDF and editable source
- ERC and DRC reports
- PCB renders and assembly drawings
- Gerber and drill archive
- BOM CSV with manufacturer parts
- Pick-and-place file when SMD assembly is used
- Bring-up measurements and inspection photos
- Revision-controlled release note
Schematic and ERC review
| Done | Check | Acceptance criteria | Evidence |
|---|---|---|---|
| Power symbols and net labels | No unconnected required power pin; every rail named | ERC report | |
| Connector pinout | Pin 1, voltage and direction clearly labelled | Schematic PDF | |
| Decoupling | 100 nF at every IC supply pin plus bulk input capacitor | Annotated schematic | |
| Protection | Input fuse/PTC, polarity and ESD strategy present | Design note | |
| I²C pull-ups | Values suit bus voltage and capacitance | Calculation |
PCB layout and DFM review
| Done | Check | Acceptance criteria | Evidence |
|---|---|---|---|
| Board outline | Closed Edge.Cuts with confirmed dimensions | Gerber viewer | |
| Clearance | Meets selected fabricator minimum plus margin | DRC report | |
| Power traces | Width supports calculated peak current | Width calculation | |
| Return paths | No high-speed signal crosses a plane split | Layer review | |
| Silkscreen | Pin 1, polarity, reference and connector functions visible | 3D/render review | |
| Test points | Accessible after assembly | Assembly drawing |
Gerber and fabrication package
| Done | File or check | Requirement | Evidence |
|---|---|---|---|
| F_Cu and B_Cu | RS-274X Gerber, correct polarity and visible outline | Gerber viewer | |
| F_Mask and B_Mask | Pads exposed only where required | Gerber viewer | |
| F_Silkscreen and B_Silkscreen | No text on exposed pads | Gerber viewer | |
| Edge_Cuts | One closed outline, no duplicate segments | DFM report | |
| Drill files | Plated and non-plated holes correctly separated | Drill map | |
| Fabrication archive | Only approved release outputs included | Release checksum |
Assembly bring-up and test
| Done | Test | Expected result | Instrument | Safety limit |
|---|---|---|---|---|
| Unpowered resistance | No short between each supply rail and ground | DMM | Do not power below expected resistance | |
| Current-limited power-up | 5 V rail stable and current below 80 mA unloaded | Bench supply and DMM | Start at 100 mA current limit | |
| 3.3 V rail | 3.20–3.40 V | DMM | Stop outside tolerance | |
| I2C scan | Expected sensor address acknowledges | Firmware and logic analyser | 3.3 V logic only | |
| UART loopback | Sent frame returns without errors | Serial terminal | Confirm common ground |
Bill of materials
Download BOM CSV| Qty | Reference | Value | Package | Manufacturer part | Supplier / SKU | Notes |
|---|---|---|---|---|---|---|
| 1 | J1 | POWER IN | TerminalBlock_2 | 1935161 | Supplier / TBD | 5 V input |
| 1 | F1 | 500 mA PTC | 1206 | MF-MSMF050-2 | Supplier / TBD | Resettable fuse |
| 1 | D1 | Reverse protection | SMA | SS14 | Supplier / TBD | Schottky diode |
| 4 | C1-C4 | 100 nF | 0603 | Generic X7R | Supplier / TBD | Decoupling |
| 1 | C5 | 47 uF 10 V | 6.3x5.8 mm | Generic low-ESR | Supplier / TBD | Bulk capacitor |
| 2 | R1-R2 | 4.7 kΩ | 0603 | Generic 1% | Supplier / TBD | I2C pull-ups |
| 1 | J2 | Sensor header | 1x06 2.54 mm | Generic | Supplier / TBD | Key pin 1 |
Assembly documentation
- Verify PCB revision against assembly drawing before kitting.
- Record reel/lot information for critical components.
- Fit lowest-profile SMD parts first, then connectors.
- Inspect polarity, pin 1, solder bridges and tombstoning.
- Clean only with a process compatible with components and flux.
- Attach annotated assembly photos and inspection result.
Fabrication notes
- FR-4, 1.6 mm finished thickness unless enclosure requires otherwise.
- Two copper layers, 1 oz finished copper.
- Lead-free HASL or ENIG finish; document selection.
- Minimum track/space and drill follow chosen fabricator capability.
- State controlled-impedance requirement explicitly: none for this design.
- Panelisation requires approval before changing board outline.
Project documentation
Release workflow
- Freeze requirements and confirm the exact component variants.
- Complete schematic/ERC review and resolve every approved exception.
- Complete layout, DRC and independent Gerber review.
- Release revision-controlled BOM, fabrication and assembly documents.
- Assemble using controlled substitutions and inspection records.
- Power through current limiting, record measurements and approve production only after all mandatory tests pass.