PegorK’s f32 might be the world’s smallest ESP32-C3 board. It measures just 9.85 x 8.45 mm, or slightly larger than the area covered by a USB Type-C connector.
A board of this size will have limited features, and besides the ESP32-C3FH4 RISC-V WiFi and Bluetooth microcontroller, it comes with a USB-C port, a ceramic antenna, and a single GPIO pin connected to an LED.
f32 specifications:
- SoC – Espressif Systems ESP32-C3FH4
- Single-core 32-bit RISC-V microcontroller @ up to 160 MHz
- Memory – 400 KB SRAM
- Storage – 4MB flash
- Wireless 2.4 GHz Wi-Fi 4 & Bluetooth 5.0
- USB – 1x USB Type-C port for power and programming
- Misc
- Tiny LED connected to GPIO10
- Ceramic antenna
- Crystal
- Power Supply – 5V via USB-C port; 3.3V LDO
- Dimensions – 9.85 x 8.45 mm (the height must be around 4-5 mm)
The PCB was designed using DipTrace and manufactured with a board thickness of 0.6mm, min hole size of 0.2mm, and min track/spacing of 4/4mil. Due to the lack of (easily accessible) GPIOs, it’s not exactly an IoT board and with rather limited usefulness, although we’ve told future versions of the board may expose some GPIOs on the sides of the PCB and improve the antenna circuitry, as the range was tested up to 38 meters. This could be potentially improved with a hardware hack that would make the board a bit thicker.
However, WiFi can be used to create a web interface, and the (closed-source?) demo firmware does just that with a user interface allowing the user to scan WiFi access points and toggle the LED. There’s also an about page.
You’ll find all resources for the project on GitHub. Unsurprisingly, the board is not for sale, so you’d have to build it yourself. Bear in mind that the world’s smallest ESP32-C3 board relies on ridiculously tiny components like the 01005 resistor pictured below and a 0.45 x 0.25mm LED. PegorK recommends people get high-quality tweezers to handle these components.
Via Hackaday
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.
Support CNX Software! Donate via cryptocurrencies, become a Patron on Patreon, or purchase goods on Amazon or Aliexpress. We also use affiliate links in articles to earn commissions if you make a purchase after clicking on those links.
