LilyGO has recently released the T-Display S3 Pro LR1121, a new ESP32-S3 development kit with a Semtech LR1121 transceiver for universal LoRa connectivity across the sub-GHz and 2.4GHz bands.
The board is an update to the earlier T-Display S3 Pro, which features a slimmer design and a 2.33-inch touchscreen display, but this new LR1121 variant adds sub-GHz and 2.4 GHz LoRa/(G)FSK support along with a voice communication kit that includes a MAX98357A I2S speaker amplifier, a PDM/I2S digital microphone, vibration motor, and a RTC. There are also programmable buttons, Qwiic connectors, and a 1/4-inch tripod mount, as well as a 2000 mAh Li-ion battery, USB-C for power, and ultra-low sleep current. These features make it suitable for applications such as LoRa walkie-talkies, Meshtastic nodes, voice-enabled IoT devices, portable dashboards, and experimental long-range wireless systems.
T-Display S3 Pro LR1121 specifications:
- Wireless MCU – Espressif ESP32-S3R8
- CPU – Dual-core Tensilica LX7 microcontroller up to 240 MHz with vector instructions for AI acceleration
- Memory – 8MB PSRAM
- Wireless – WiFi 4 and Bluetooth 5.0 LE + Mesh connectivity
- Storage
- 16MB SPI flash
- MicroSD card socket (Not confirmed by the company, I see the slot on top of the USB-C)
- Display – 2.33-inch 480×222 IPS full-color capacitive touchscreen LCD using ST7796 SPI controller
- Wireless
- Wi-Fi & Bluetooth – 2.4GHz Wi-Fi 4 (802.11 b/g/n) and Bluetooth 5.0 LE / Mesh (via ESP32-S3)
- LoRa / Sub-GHz – Semtech LR1121 LoRa/(G)FSK half-duplex transceiver
- Frequency Bands – 150 – 960MHz (Sub-GHz), 2.4GHz ISM, 2.1GHz S-Band, 1.55GHz L-Band
- Protocol support – LoRaWAN, Meshtastic (hardware capable), custom LoRa P2P
- Audio
- Microphone – MP34DT05-A (PDM) or MSM261S4030H0R (I2S)
- Speaker – MAX98357A I2S Amplifier
- USB – USB Type-C port for power and programming (OTG supported via SY6970)
- Antennas – Dual external LoRa antennas (Sub-GHz and 2.4GHz)
- Expansion
- 9-pin female header giving access to VBUS, BAT, 5x GPIOs, VBUS, 3.3V, BAT, GND
- 2x QWIIC connectors
- Misc
- Built-in vibration motor (PWM controlled)
- BM8563 or PCF85063ATL Real-Time Clock (RTC)
- Reset and Boot buttons (on the left side)
- User buttons (IO12+IO16 on the right side)
- Power
- 5V via USB Type-C
- Built-in 2,000mAh Li-ion battery (significantly larger than the 470mAh in the base model)
- Ultra-low deep sleep current (~30 µA reported)
- Dimensions – 111 x 52 x 29 mm (L x W x H including antenna)
- Mounting – 1/4-Inch screw thread on the bottom for tripod mounting
After writing up the specification, it’s clear that some hardware features from the earlier versions have been dropped on this model, including the camera interface, the LTR-553ALS-0 ambient light and proximity sensor, and the capacitive touch button in the center. Though the placeholders appear to still be there, LilyGO does not clearly mention whether the sensor is there or it’s just a dummy.
The device is larger and thicker compared to the standard T-Display S3 Pro due to the 2000mAh battery and the expansion shield. The pinout diagram shows that the LR1121 is connected via SPI, whereas the touch panel and display use standard GPIOs similar to the original S3 Pro.
On the software side, LilyGO provides examples for Arduino IDE and PlatformIO on GitHub. Additionally, the repository includes samples for LoRa “PingPong” tests, a walkie-talkie demo using the onboard audio hardware, and various other example sketches. Since the hardware is effectively an ESP32-S3 with a Semtech LR1121 radio, like the LILYGO’s T-LoRa Pager, it should be compatible with open-source projects like Meshtastic, but at the time of writing, official stable firmware is not yet available, though Alpha versions for the LR1121 exist.
The LilyGO T-Display S3 Pro LR1121 is available on AliExpress for $85.98, Amazon for $75.00, or the LilyGO store for $65.29. It’s a fully assembled kit with the T-Display S3 Pro unit, the LR1121 expansion backplate, and a 2,000mAh battery.
Debashis Das is a technical content writer and embedded engineer with over five years of experience in the industry. With expertise in Embedded C, PCB Design, and SEO optimization, he effectively blends difficult technical topics with clear communication
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