LOLIN S3 Mini is a tiny ESP32-S3 WiFi and Bluetooth IoT development board that follows the Wemos D1 Mini form factor and supports its equally tiny stackable shields to add relays, displays, sensors, and so on.
Wemos/LOLIN introduced their first ESP32-S3 board last year with the LOLIN S3 board with plenty of I/Os and an affordable $7 price tag. But I prefer the company’s Mini form factor because of its size and the ability to select add-on boards to easily add a range of features to your projects. So I’m pleased to find out the company has now launched the LOLIN S3 Mini following the ESP32-C3 powered LOLIN C3 Mini board unveiled in March 2022.
LOLIN S3 Mini specifications:
- WiSoC – Espressif Systems ESP32-S3FH4R2
- CPU – dual-core Tensilica LX7 @ up to 240 MHz with vector instructions for AI acceleration
- Memory – 512KB RAM, 2MB PSRAM
- Storage – 4MB QSPI flash
- Connectivity – 2.4 GHz WiFi 4 and Bluetooth 5.0 LE with support for long-range, up to 2Mbps data rate, mesh networking
- Antenna- PCB antenna
- USB – USB Type-C port for power and programming
- Expansions – 2x 16-pin headers with up to 27x GPIOs, ADC, DAC, I2C, SPI, UART, USB OTG, etc…
- Misc – 1x RGB LED (IO47), Reset button, user-programmable button (IO0)
- Power Supply – 5V via USB Type-C port
- Dimensions – 34.3 x 25.4mm
- Weight – 3 grams
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The board comes pre-installed with MicroPython, but can also be programmed with Arduino and the ESP-IDF. You’ll find tutorials to get started with either MicroPython or Arduino in the Wiki along with the PDF schematics and dimensions file.
The sensor shields available for Wemos D1 Mini and compatible boards, like the S3 Mini featured in this post, could make it especially interesting for TinyML applications. Note the shiels/add-on boards only use the 8-pin headers on each side of the boards, and not the other two inner rows which could be used for another purpose.
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LOLIN is selling the S3 Mini board for $5 plus shipping, and the D1 Mini shields range from 60 cents (button shield) to $6.90 (SGP30 TVOC air quality shield).
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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.
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