PCB Design: Grow Tent Controller Boards

1. Project Overview & Architecture
The goal of this project is to design a set of modular, decentralized expansion PCB boards for grow tent automation. Instead of a rigid central mainboard, each expansion board functions as an independent node powered by a localized ESP32-C3 Supermini module, communicating via Wi-Fi/MQTT through ESPHome into Home Assistant.
To reduce clutter and eliminate the need for multiple external power supplies, all boards will share a common power distribution concept: 12V DC Input (via standard 5.5x2.5mm barrel jacks or terminal blocks) with onboard step-down regulation (e.g., Buck converters) to supply 5V and 3.3V where needed, allowing a single 12V notebook power supply to be daisy-chained across boards.

2. General Requirements for All Boards
Microcontroller: Socket/Footprint for an ESP32-C3 Supermini.
Power Input: 12V DC input connector (with daisy-chain capability / parallel output terminals to pass 12V to the next board).
Power Regulation: Onboard voltage regulation to step down 12V to 5V and 3.3V for logic and sensors.Form Factor: Compact designs suitable for standard DIN rail mounting enclosures (or compact stand-alone project boxes).
Design Files: Delivery of complete Gerber files, schematic diagrams (KiCad or Altium Designer), BOM (Bill of Materials with part numbers/sources), and manufacturing files.

Board 1: Fan Control Board (PWM & 12V Fans)
Description: A specialized board designed to control multiple 12V PC-style fans or compatible ventilation hardware independently via PWM signals. It includes power distribution and individual signal lines for speed control and tachometer feedback. Detailed pin assignments and driver IC choices will be provided to the awarded designer.

Board 2: LED & 0-10V Control Board
Description: A control board dedicated to managing dimmable grow lights and equipment that accept standard 0-10V analog or PWM control signals (e.g., via RJ12 connections). It provides multiple individually addressable output ports with proper signal conversion circuitry.

Board 3: Sensor Board
Description: A multi-sensor interface board designed to aggregate various environmental and liquid sensors (such as temperature, humidity, water level, pH, and EC sensors). It features appropriate signal conditioning and analog-to-digital conversion inputs to ensure accurate readings.

Board 4: Circulation & Relay Board (AC Switching)
Description: A high-voltage switching board designed to control external AC devices like multi-stage inline fans or humidifiers. It features an AC mains power input (via a C13 appliance plug or similar inlet) and safe, optically isolated relay outputs connected to secure terminal blocks for external AC wiring.

4. Intellectual Property & Rights Transfer (Legal Disclaimer)
IP Assignment and Non-Disclosure Agreement Terms:
By accepting this project and providing design services, the designer (Contractor) explicitly agrees and acknowledges that:
Exclusive Ownership: All intellectual property rights, design files, schematics, Gerber files, BOMs, documentation, and any derivative work created under this agreement shall be the sole and exclusive property of the Client from the moment of creation.
Full Rights of Use & Modification: The Client is granted unlimited, worldwide, perpetual, and exclusive rights to use, modify, adapt, manufacture, commercialize, open-source, or distribute the resulting hardware designs without any restrictions or additional fees.
Non-Use & Confidentiality: The Contractor agrees not to use, reuse, offer, publish, sell, or share these designs, schematics, or layout concepts with any third party, nor to manufacture or market them for personal gain or for other clients, without the explicit written consent of the Client.