GrowTek's ESP32 Hydroponic Automation Board Includes Load-Cell Amplifiers, 2A MOSFETs

Hydroponic specialist GrowTek has designed an automation board built around an Espressif ESP32 microcontroller and offering eight 2A MOSFETs and four HX711 load-cell amplifiers — plus broad DC power input support.

"It's special because I haven't seen any other boards that include all of these components on one board," GrowTek's founder explains DJ Skone of his design. "I made this for automating hydroponics."

Those features start with an ESP32 microcontroller that is fed from a 9-16V DC power input — which includes a secondary LDO output for the HX711 load-cell amplifier chips, offering a 5V excitation voltage for boosted resolution on weight readings.

Data from the four HX711s — pulled from load cells connected over RJ45 jacks, to simplify wiring — can then be used to trigger one or more of the eight on-board MOSFETs, each rated at 2A, to drive motors, solenoids, or relays.

The board doesn't quite come ready to use out-of-the-box, though: "There is no programmer on this board," Skone explains. "The UART pins are available on the board for programming with your choice of programmers. I use a CP2102 board for programming with Arduino IDE. These are available on Amazon for $5-$10."

Skone is selling the board via the GrowTek Tindie store at $45 a unit fully assembled; buyers will need JST-XH5 connectors, not included, to make use of the MOSFETs and RJ45 connectors to make use of the HX711s.