It looks like ESP32-C3 floodgates have opened. We’ve just written about several NodeMCU ESP32-C3 boards, and now there’s another board with the RISC-V WiFI & Bluetooth processor. Meet LilyGo TTGO T-OI PLUS equipped with a 16340 battery holder.
Getting a battery-powered ESP32-C3 board could prove to be very interesting as ESP32-C3 power consumption is much lower than ESP8266 and ESP32, notably in deep sleep mode, where the RISC-V processor consumes just 5uA, against 20 uA for ESP8266 and ESP32, and the difference is even greater in light sleep mode (ESP8266: 2000 uA vs ESP32-C3: 130 uA).
LilyGo TTGO T-OI PLUS specifications:
- SoC – Espressif Systems ESP32-C3 single-core RISC-V processor @ 160 MHz with 2.4 GHz WiFi, Bluetooth 5.0 LE
- Storage – TBD flash (probably 2MB or 4MB)
- Antenna – Ceramic antenna and IPEX connector
- USB – USB-C port for power and programming
- Expansion
- 2x 8-pin headers with 12x GPIO, 1x SPI, 1x UART, 3x ADC, 5V, 3.3V, GND
- 4-pin I2C Grove connector
- Misc – Power and charging LEDs, Reset button, power switch
- Power Supply
- 5V via USB Type-C port
- Holder for 3.7V 16340 LiPo battery plus charging circuit
- Dimensions – 45.7 x 25.8 x 15.8 mm
The PCB reads “mini D1 PLUS”, which reminds me of the Wemos D1 mini ESP8266 board I tested with expansion modules like relays and temperature sensors in 2016. And while the dimensions are not exactly the same, the pinout of the headers is the same, and so the Wemos D1 Mini expansion modules are also compatible with TTGO T-OI PLUS.
LilyGo points to Github for documentation and sample code with one Arduino sketch scanning WiFi networks, as well as Windows & Mac drivers for CH34x USB to serial chip. Note that the repository is for the earlier TTGO T-OI board based on ESP8266 chip. Arduino ESP32 core’s development branch already supports ESP32-C3, but at this time, the code may have to be tweaked to make it work on third-party boards, as I’d assume it has been developed on the official ESP32-C3-DevKitM-1 development kit.
LilyGo TTGO T-OI PLUS can be purchased on Aliexpress for $4.68 plus shipping, or $4.49 if you’d like to do away with the battery holder for a thinner board and/or to solder your own battery.



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.