ESP32 HAT

ESP32-C6 Raspberry Pi Zero HAT

KiCad design files for a Raspberry Pi Zero form-factor HAT carrying an Espressif ESP32-C6-MINI-1 module. The board gives a Raspberry Pi (or any 40-pin host) 2.4 GHz Wi-Fi 6, Bluetooth 5 LE, Zigbee and Thread connectivity, and can also be used stand-alone over its USB-C port. This repository contains the hardware design only — schematic, PCB and design rules; no firmware.

Overview

The board is a four-layer, 1.6 mm PCB measuring 30 x 65 mm, with two internal power planes.

• ESP32-C6-MINI-1-H8 module — RISC-V SoC with 8 MB flash and an on-module PCB antenna, providing Wi-Fi 6, Bluetooth 5 LE, Zigbee and Thread.
• Power — an on-board NCP1117 linear regulator derives 3.3 V (up to 1 A) so the HAT can run from either the host header or USB-C.
• Host interface — a 40-pin, 2.54 mm Raspberry Pi-style header connects the ESP32 to the host.
• USB-C and UART bridge — a USB-to-UART bridge allows programming and console access without the Pi in circuit.
• Expansion — a 15-pin, 2.54 mm auxiliary header breaks out spare ESP32 GPIO.
• Status and control — two WS2812B-2020 addressable RGB LEDs (Wi-Fi and Zigbee status) and three 5 x 5 mm normally-open SMD tactile switches. The WS2812 data line can be strapped to GPIO10, GPIO12, GPIO18 or GPIO21.
• Mechanical — four 2.5 mm mounting holes and 3 mm corner radii, matching the Pi Zero outline.

Requirements

Hardware

• Raspberry Pi Zero (or another 40-pin, 2.54 mm host header) — optional; the HAT also runs stand-alone.
• USB-C cable for power, programming and console.

Software

• KiCad 10.0 or later — earlier versions will not open these files.
• kicad-cli (shipped with KiCad) for headless export and rule checks.

Getting the source

git clone git@github.com:Rufilla/ESP32_HAT.git
cd ESP32_HAT

Open esp32_HAT.kicad_pro in KiCad. Footprint libraries are resolved through the local fp-lib-table.

Building

Generating the manufacturing outputs headlessly:

kicad-cli sch export pdf  esp32_HAT.kicad_sch -o production/esp32_HAT-schematic.pdf
kicad-cli sch export bom  esp32_HAT.kicad_sch -o production/esp32_HAT-bom.csv
kicad-cli pcb export gerbers esp32_HAT.kicad_pcb -o production/
kicad-cli pcb export drill   esp32_HAT.kicad_pcb -o production/

production/, output/ and exported BOM/netlist files are git-ignored, so fabrication outputs are regenerated rather than committed.

Testing

Run the electrical and design rule checks before releasing a revision. Custom design rules live in esp32_HAT.kicad_dru.

kicad-cli sch erc esp32_HAT.kicad_sch
kicad-cli pcb drc esp32_HAT.kicad_pcb --severity-error

Project structure

esp32_HAT.kicad_pro    KiCad project: DRC severities, net classes, board stack-up
esp32_HAT.kicad_sch    Schematic
esp32_HAT.kicad_pcb    PCB layout (4 layers, 1.6 mm, 30 x 65 mm)
esp32_HAT.kicad_dru    Custom design rules for the fabricator
system_block.kicad_sch System block diagram
fp-lib-table           Project footprint library table
esp32_HAT.png          Board render used in this README
docs/images/           Images referenced by documentation

Security

To report a security concern in this design, email hello@rufilla.com rather than opening a public issue.

Licence

Apache License, Version 2.0 — see LICENSE.

Third-party components keep their own licences. KiCad symbols and footprints taken from the standard KiCad libraries remain under the KiCad Library Licence; the ESP32-C6-MINI-1/U module and other parts are covered by their manufacturers' terms.

Support

Rufilla Ltd · Building D5, Culham Campus, Abingdon, Oxfordshire, UK, OX14 3DB hello@rufilla.com · +44 (0)1865 601201 · www.rufilla.com

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