Greenhouse Controller
A complete wireless greenhouse monitoring system designed exclusively from Circuit Issues templates — no custom power or RF circuits from scratch. This project shows exactly how the catalog templates fit together on a real product.
System photo — coming with build log
System overview
The greenhouse controller monitors soil moisture, air temperature, humidity, and ambient light. All data is exposed over WiFi via ESPHome and visualised in Home Assistant. The board is powered from a USB-C supply or a 1S Li-Ion cell for portable or outdoor deployment.
| MCU | 0140 ESP32S3 Core Controller |
| Power input | Solar + battery workflow via 0120 MPPT charger |
| Rail supply | 0101 Buck 3.3V/5V up to 2A |
| Load control | 0110 Low-side switch for pumps/valves/fans |
| Telemetry | 0010 Current/Power measurement block |
| Sensors | Soil moisture (ADC), DHT22 (temperature/humidity), light (LDR) |
| Connectivity | WiFi via ESP32S3 |
| Firmware | ESPHome / compatible with Arduino |
| PCB | 2-layer, 60 × 45 mm, open-source (KiCad) |
Templates used
Every major subsystem on this board came directly from a Circuit Issues block: charging, regulation, switching, telemetry, and control.
ESP32-S3 Core Controller
Production-ready ESP32S3 core with USB-C programming, auto-download circuit, and documented RF keep-out guidance.
MPPT Solar Charger — Acid Output
MPPT charger block optimized for solar input to acid-battery charging workflows in embedded power systems.
Buck Power Supply 3.3V/5V 2A
Dual-output buck supply block providing regulated rails for digital and peripheral sections.
Low-side Switch 5A 24V
Low-side switching block for pumps, valves, fans, and other inductive or resistive loads up to 24V/5A class.
Current/Power Measurement 5A 25V
Measurement block for current and power telemetry in embedded power systems.
Key integration decisions
Shared 3.3 V rail
The 0101 buck output feeds the 0140 controller and the 0010 telemetry path. Noise-sensitive return paths are stitched at controlled star points near the regulator output.
Power-path orchestration
Solar and battery behavior is managed through the 0120 charger stage, then stepped to stable logic rails through 0101 before distribution to control and sensing blocks.
Measurement + switching feedback loop
0010 telemetry informs firmware decisions while 0110 executes actuator control. This creates a repeatable closed loop for energy-aware greenhouse automation.
Single 2-layer PCB integration
All five blocks are integrated onto one 2-layer PCB while preserving critical layout constraints documented in each block package.
Build log
4 posts plannedWhy I Built a Greenhouse Controller From Templates
PlanningComing soonThe motivation, system requirements, and why reusing proven building blocks beats designing from scratch every time.
Integrating Five Blocks on One PCB
HardwareComing soonCombining 0140, 0120, 0101, 0110, and 0010: how rails, sensing, switching, and control fit together in one system.
Board Bring-Up and Sensor Calibration
DebugComing soonFirst power-on checklist, probing the rails, flashing firmware over USB-C, and calibrating the soil-moisture ADC channel.
ESPHome Integration and Home Assistant Dashboard
FirmwareComing soonWriting the ESPHome YAML, mapping GPIO to sensors, and wiring the dashboard for temperature, humidity, and soil moisture.
Video walkthrough
Video coming with build log series
Build your own project from templates
Get the IoT Starter Bundle to begin with 0140 + core power blocks, then expand as additional preview blocks move to full release.