TTGO T-Higrow is a WiFi & Bluetooth connected soil temperature & moisture sensor

LilyGO has made plenty of ESP32 “TTGO” boards with various features be it PoE, battery support, OLED display, cellular connectivity, and even a devkit in watch form factor.

The latest product from the company specifically targets smart farming/gardening as TTGO T-Higrow embeds either DHT11 temperature and humidity sensor or BME280 temperature, humidity, and barometric sensor to report soil temperature and moisture over Bluetooth or WiFi. It can also come as a kit with a battery and a 3D printed enclosure.

TTGO T-Higrow board specifications:

SoC – Espressif Systems ESP32 dual-core LX6 processor @ up to 240 MHz with 520 LB SRAM, Wi-Fi & Bluetooth
Storage – 4MB QSPI flash
Wireless
- 2.4 GHz 802.11b/g/n WiFi 4 up to 150 Mbps
- Bluetooth 4.2 BR/EDR and BLE
Sensors
- Option 1 – DHT11 temperature and humidity sensor
- Option 2 – BME280 temperature, humidity, and barometric sensor
Expansion –
- 2x 12-pin through holes with UART, SPI, SDIO, I2C, PWM, I2S, IR, GPIOs, capacitive touch sensing, ADC, ADC
- 4-pin I2C connector for external waterproof sensors
Debugging – CP2104 USB to TTL chip
Misc – 1x user button, 1x wake up button, 40MHz crystal oscillator
Power Supply
- 5V/1A via USB-C port
- 2-pin header for 3.7 Lithium battery; TP4054 charging chip
Power Consumption – Operating: about 150 mA; sleep current: 220 uA
Temperature Range – -40°C to +85°C
Dimensions – 155 x 35 x 8.2 mm
Weight – 13.65g

The company provides Arduino sample code showing sensor data in a web interface, firmware file, PDF schematics, 3D print files, and other documentation on Github.

The board ships with unsoldered headers and the battery cable, but there’s also a kit with the DHT11 or BME280 version of TTGO T-Higrow that adds a 3D printed case and a 200 mAh battery.

I could not find any information about battery life, as it will depend on the implementation and most notably how long the board stays in deep sleep mode before it wakes up to report sensors data to your IoT gateway or selected cloud service. I can see deep sleep is implemented using the user button in the demo code.

LilyGO sells TTGO Higrow boards and kits for $9.92 to $16.23 on Aliexpress.

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.