Seon Rozenblum's OMGS3 Is His Smallest Espressif ESP32-S3 Development Board Yet

Seon Rozenblum, also known as the "Unexpected Maker," has expanded his Espressif ESP32-S3 microcontroller development board family, unveiling what he claims is "the world's smallest, fully-featured" board to include the part: the OMGS3.

"OMGS3 is the world's smallest, fully-featured ESP32-S3 board/module," writes Rozenblum of his latest design. "It's packed with amazing features and peripherals, wireless connectivity and stacks of flash and PSRAM [Pseudo-Static RAM], and can be surface mounted to a carrier PCB or have wires soldered to the pads."

This isn't Rozenblum's first board to feature the Espressif ESP32-S3, a part which pre-dates the company's move to RISC-V exclusivity and includes two Tensilica Xtensa LX7 cores running at up to 240MHz and a RISC-V core as an ultra-low power coprocessor: back in September 2022 he unveiled the TinyS3, FeatherS3, and ProS3.

The OMGS3, though, is the smallest of the lot — beating even the TinyS3 — thanks to the decision to drop breadboard-friendly pint headers in favor of surface-mount pads under the board's underside. These bring out 17 of the ESP32-S3's general-purpose input/output (GPIO) pins, along with data pins for a USB connection — the board itself lacking any such niceties.

Elsewhere on the compact layout is a charging circuit and fuel gauge for an optional lithium-polymer battery, 8MB of flash, 2MB of PSRAM, an antenna for the single-band 802.11b/g/n Wi-Fi and Bluetooth 5.0 Low Energy (BLE) radios, a 3.3V regulator delivering up to 700mA, and a single low-power RGB LED for status notifications or tiny discos.

More information on the board is available on Rozenblum's website, while a GitHub repository includes a KiCad project for an OMGS3 carrier board reference design under an unspecified license. The OMGS3 itself, meanwhile, is available to order from the Unexpected Maker web store at $17, with bulk discounts available.