LILYGO T-QT Pro ESP32-S3 Miniature Development Board with 0.85" IPS LCD (Soldered)

Specifications

• Microcontroller: ESP32-S3FN4R2 (Dual-core, up to 240 MHz)

• Flash Memory: 4MB

• PSRAM: 2MB

• Wireless: Wi-Fi (802.11 b/g/n) & Bluetooth 5 (LE)

• Display Size: 0.85 inches diagonal

• Display Driver: GC9107

• Resolution: 128 x 128 pixels

• Power/Data Interface: USB Type-C

• Battery Support: External LiPo via rear solder pads/connector (Charging/Discharging supported)

• Expansion: STEMMA QT / Qwiic (JST-SH 1.0mm 4-PIN)

• Dimensions: 33mm (L) x 18mm (W) x 14mm (H)

Key Applications and Projects

• DIY Smartwatches: Utilizing the tiny screen, battery circuit, and Bluetooth connectivity to push notifications from a smartphone to a custom 3D-printed wrist wearable.

• Miniature Tamagotchis / Digital Pets: Programming a retro-style digital pet that utilizes the Wi-Fi to interact with other T-QT Pro devices.

• Discrete Server Monitors: Tucking the tiny screen under a PC monitor to constantly display live server ping or CPU temperature statistics.

Unlock New Capabilities (Project Evolution) The Wearable Environmental Tracker: Turn this tiny board into a powerful personal environmental monitor. Solder a tiny 150mAh LiPo battery to the rear battery pads. Then, plug a BME680 environmental sensor into the STEMMA QT / Qwiic port. You can program the ESP32-S3 to read the temperature, humidity, and volatile organic compounds (VOCs/Air Quality) and display them on the 0.85-inch screen as a sleek, animated gauge. Clip it to your backpack, and you have a real-time air quality monitor wherever you go!

PACKAGE INCLUDED

• 1 x LILYGO T-QT Pro Board

• 1 x Power/Battery Cable

• 2 x Male Pin Headers (Unsoldered)

• 1 x JST 2.0mm 2P

Downloads & Links

• LILYGO T-QT Pro Github Link

FREQUENTLY ASKED QUESTIONS (FAQ)

1. What microcontroller drives this board? It is powered by the Espressif ESP32-S3FN4R2 microprocessor.

2. What are the specifications of the onboard screen? The screen is a very small 0.85-inch diagonal IPS TFT LCD. It has a resolution of 128x128 pixels and is driven by the GC9107 chip.

3. Does this version have a touchscreen? No, the 0.85-inch display is a standard non-touch LCD.

4. How much memory does the board have? It features 4MB of Flash memory and 2MB of PSRAM.

5. Why is PSRAM important on this board? The 2MB of PSRAM allows the ESP32-S3 to create large frame buffers in memory, preventing crashes and ensuring smooth screen updates when using graphic libraries like LVGL.

6. Can I power this board with a battery? Yes. The board supports external batteries and has a built-in charging and discharging circuit.

7. Where do I connect the battery? There are specific pads on the rear of the board labeled for battery connection (+ and -), or you can use the provided cable.

8. How do I program this board? You connect it to your computer via the onboard USB Type-C port. It can be programmed using the Arduino IDE, PlatformIO, or MicroPython.

9. What settings should I use in the Arduino IDE? Select the "ESP32S3 Dev Module". Ensure you set "USB CDC On Boot" to Enabled, Flash Size to 4MB, and PSRAM to OPI PSRAM.

10. Is there an easy way to connect I2C sensors? Yes. The board features a STEMMA QT / Qwiic compatible JST-SH 1.0mm 4-PIN connector (mapped to IO44 and IO43), allowing you to plug in external I2C sensors without any soldering.

11. Does it support Wi-Fi? Yes, it features standard 2.4 GHz Wi-Fi (802.11 b/g/n) for connecting to your local network or the internet.

12. Does it support Bluetooth? Yes, the ESP32-S3 chip supports Bluetooth 5 (LE).

13. What are the physical buttons on the board do? There are two physical buttons on the bottom edge: one is a Reset button (IO0), and the other is a user-programmable Key (IO47).

14. What are the exact dimensions of the board? The main body (including the acrylic cover) measures 33mm in length, 18mm in width, and 14mm in height.

15. Can I use an external Wi-Fi antenna? Yes. The board has a default onboard antenna, but it also features a tiny u.FL/IPEX connector on the back to attach a high-gain external antenna for longer range.

16. How do I switch to the external antenna? There is a tiny resistor pad array near the antenna connector that must be desoldered and bridged differently to physically switch the RF path from the onboard antenna to the external connector.

17. Do I need to solder the header pins? Yes. The board comes with male and female header strips that are left unsoldered in the package. You must solder them yourself if you wish to use a breadboard.

18. What GUI libraries are recommended for this board? The TFT_eSPI library is highly recommended for driving this specific GC9107 display quickly and efficiently.

19. Which pins are used internally for the LCD? The GC9107 LCD uses several internal pins including LCD_BL (IO10), LCD_DC (IO06), LCD_CS (IO05), LCD_CLK (IO03), LCD_MOSI (IO02), and LCD_RES (IO01).

20. What logic voltage do the GPIO pins use? Like all ESP32 chips, the GPIO pins operate strictly on 3.3V logic. Do not apply 5V directly to any GPIO pin, or you will destroy the microcontroller.