🔧 Detailed Project Description

This project is a compact, powerful, and cost-effective 8-channel smart home automation board built around the ESP32-C3 SuperMini. Designed for DIY makers, automation enthusiasts, and developers, this PCB provides everything you need to control home appliances like fans, lights, and sockets over Wi-Fi, with support for Home Assistant, Tasmota, or custom Arduino firmware.

🔌 Core Components & Functional Overview

ESP32-C3 SuperMini

A low-power, RISC-V based microcontroller with built-in Wi-Fi and Bluetooth 5.0.

Used here as the brain of the board to control all 8 relays via GPIO.

Fully compatible with ESPHome, Tasmota, Arduino IDE, and MicroPython.

8-Channel Relay Interface

Controlled via a ULN2803A Darlington transistor array.

Each relay can switch up to 10A at 250V AC or 30V DC.

LED indicators on each relay channel show active status at a glance.

Power Supply Section

The board takes direct AC 100–240V input, using the HLK-PM01 AC-DC module to convert it safely to 5V DC.

A LM2596 buck converter then steps down 12-35v to 5v power the ESP32-C3.

I2C and GPIO Expansion Headers

Dedicated 4-pin I2C headers for adding peripherals like OLED displays, temperature sensors (DHT11, BMP280), RTC modules, etc.

Extra GPIO headers (D10, D12, D20) exposed for buttons, motion sensors, or other digital inputs.

Safety & Isolation

AC section clearly separated and labeled.

Optional DC barrel jack input (12V) supported with onboard regulator for flexible deployment.

📡 Firmware & Platform Support

You can choose any of the following to control the board:

✅ ESPHome

Ideal for Home Assistant users. Easily configurable via YAML with relay control, automation, OTA updates, and MQTT integration.

✅ Tasmota

Flash via serial and manage through Tasmota’s web UI. MQTT-ready and fully customizable without coding.

✅ Arduino IDE

Write and upload custom firmware using the Arduino IDE and ESP32 board libraries. Ideal for developers and hobbyists.

🔋 Power Input Options

Primary Input: 230V AC via terminal block → HLK-PM01 → 5V

Secondary Option: DC jack (DC 12–35V) → LM2596 buck converter → 5V

Optional power switch to safely cut power during wiring or installation

📐 PCB Design Highlights

2-layer, compact layout with clean silkscreen labeling

Professional design using EasyEDA

Screw terminals for high-current relay output

Sufficient trace width and copper fill for safety and reliability

Clearly labeled headers and GPIO pins

Open Source Hardware licensed

🧠 Example Use Cases

Remote switching of lights, fans, pumps

Room-based appliance control

Wall-mounted smart switch panel

IoT automation scenes with sensors and timers

Voice assistant integration (Alexa, Google)

📢 Why This Project?

This board solves common problems DIYers face in home automation:

No more breadboards or jumper wires

Clean and permanent installation

Compatible with multiple software platforms

Professional-quality design with clear labels and flexibility

Whether you’re upgrading your smart home or building a controller from scratch, this board is the perfect mix of simplicity, reliability, and customization.

📬 Contact & License

📨 Email: electroiot.in@gmail.com

🌐 Website: https://electroiot.in

🛠️ License: Open Source Hardware – Feel free to modify and improve!

i WIll Upload Code and Video Soon