ESP32-C3 Relay Board Design for Smart-Lock
Budget: €30 – €250 EUR
Hi!
I’m working on a small relay board design using the ESP32‑C3 for a smart-lock system I’m developing. It’s part of a future product I’m exploring on my own — I’m not a company, just an individual-
The board is meant to control a 12 V electromagnetic lock via BLE. I plan to assemble around 20–50 units through JLCPCB for early testing and iteration.
What I need
A full KiCad v7 design package that’s ready for JLCPCB (fabrication + assembly), including:
Schematic and PCB layout (≤ 50×50 mm, 2-layer FR-4, 1 oz copper)
Gerbers + drill files (Excellon)
BOM (.csv with LCSC part numbers) — mark DNP for the UART header
CPL (.csv) for SMT assembly (I’ll hand-solder the TH parts)
A short README with pinout (for flashing) and a rough power budget
I’d appreciate your input if you spot any smart simplifications or improvements — as long as the board stays compact, clean, and easy to assemble.
Key specs
Input: 12 V DC (10.2–13.8 V), with reverse polarity protection + TVS
ESP32‑C3‑WROOM‑02‑N4 (certified module)
Relay: SPDT, 12 V coil, 10 A (e.g. Songle SRD or Omron G5Q footprint)
Driver: AO3400A N-MOSFET + gate resistor
Flyback diode: FR107 or SS14
Buck converter: ~500 mA (MP1470 family or similar)
6-pin UART header (only populated in development)
Relay control on GPIO5 with 10k pull-down
3.5 mm screw terminals (VIN, NO/COM/NC)
4 × Ø3 mm mounting holes
Layout guidelines
Solid GND pour
No traces under the ESP32 antenna
≥ 3 mm wide relay traces, routed away from RF section
Continuous GND reference, no unnecessary stubs
≥ 1.8 mm creepage on relay side (expandable if needed)
Timeline & Payment
I’d like to get this done within 10 days of starting.
Budget is around $100 — feel free to suggest what works for you.
I’ll create a milestone upfront and release it once the files successfully pass JLCPCB’s online fabrication checks.
(If you notice anything unclear or missing, I’d love your input.)
Warranty
If there’s a clear schematic or layout mistake that causes the board to fail, I’d expect a corrected version at no extra cost.
Thanks — I’ll reply within 24 hours!
I’m working on a small relay board design using the ESP32‑C3 for a smart-lock system I’m developing. It’s part of a future product I’m exploring on my own — I’m not a company, just an individual-
The board is meant to control a 12 V electromagnetic lock via BLE. I plan to assemble around 20–50 units through JLCPCB for early testing and iteration.
What I need
A full KiCad v7 design package that’s ready for JLCPCB (fabrication + assembly), including:
Schematic and PCB layout (≤ 50×50 mm, 2-layer FR-4, 1 oz copper)
Gerbers + drill files (Excellon)
BOM (.csv with LCSC part numbers) — mark DNP for the UART header
CPL (.csv) for SMT assembly (I’ll hand-solder the TH parts)
A short README with pinout (for flashing) and a rough power budget
I’d appreciate your input if you spot any smart simplifications or improvements — as long as the board stays compact, clean, and easy to assemble.
Key specs
Input: 12 V DC (10.2–13.8 V), with reverse polarity protection + TVS
ESP32‑C3‑WROOM‑02‑N4 (certified module)
Relay: SPDT, 12 V coil, 10 A (e.g. Songle SRD or Omron G5Q footprint)
Driver: AO3400A N-MOSFET + gate resistor
Flyback diode: FR107 or SS14
Buck converter: ~500 mA (MP1470 family or similar)
6-pin UART header (only populated in development)
Relay control on GPIO5 with 10k pull-down
3.5 mm screw terminals (VIN, NO/COM/NC)
4 × Ø3 mm mounting holes
Layout guidelines
Solid GND pour
No traces under the ESP32 antenna
≥ 3 mm wide relay traces, routed away from RF section
Continuous GND reference, no unnecessary stubs
≥ 1.8 mm creepage on relay side (expandable if needed)
Timeline & Payment
I’d like to get this done within 10 days of starting.
Budget is around $100 — feel free to suggest what works for you.
I’ll create a milestone upfront and release it once the files successfully pass JLCPCB’s online fabrication checks.
(If you notice anything unclear or missing, I’d love your input.)
Warranty
If there’s a clear schematic or layout mistake that causes the board to fail, I’d expect a corrected version at no extra cost.
Thanks — I’ll reply within 24 hours!