Espressif's ESP32-S31 Dual-Core Edge-Smarts Microcontroller Hits the Mainstream, Launches at $4.51

Espressif has announced that its dual-core ESP32-S31, a high-performance RISC-V microcontroller targeting on-device machine learning (ML) at the edge, has entered mass production — and you can order the chips now, if you're willing to pay a hefty shipping fee.

"Designed for next-generation AIoT [Artificial Intelligence of Things] applications," Espressif says of its latest wireless microcontroller part, "ESP32-S31 is a high-performance dual-core RISC-V SoC with comprehensive wireless connectivity, making it ideal for smart home hubs, smart speakers, edge AI devices, industrial automation, and more."

The company announced ESP32-S31 development boards, the CoreBoard and Korvo, earlier this year as the first to be built around the part. Designed around the free and open-source RISC-V instruction set architecture, the ESP32-S31 doubles the usual core count to two 32-bit RISC-V cores running at up to 320MHz, includes a third ultra-low-power coprocessor, includes 512kB of static RAM (SRAM) for the main cores and 32kB for the ULP coprocessor, comes with 320kB of flash ROM with support for external flash and pseudo-static RAM (PSRAM) expansion, and includes 60 general-purpose input/output (GPIO) pins.

The chip's radio block in includes single-band 2.4GHz Wi-Fi IEEE 802.11b/g/n and 802.11ax connectivity, Bluetooth 5.4 Classic and Low Energy (BLE) connectivity with Bluetooth Mesh 1.1 support, and IEEE 802.15.4-2025 compatibility with support for Thread 1.4, Zigbee 3.0, and Matter smart home standards. There's also gigabit Ethernet on board, for wired networking.

For media projects there's an on-board JPEG codec, a 2D graphics core dubbed the Pixel Processing Accelerator (PPA), an audio sample-rate converter, a coordinate rotation digital computer (CORDIC) accelerator, and a hardware controller for LCD output and camera input. Analog support includes two 12-bit successive-approximation analog-to-digital converters (SAR ADCs) with up to 16 channels and four digital-to-analog converters, two 10-bit resolution and two 12-bit resolution, and up to 14 capacitive touch channels.

Software compatibility comes courtesy of Espressif's in-house ESP-IDF development framework, and is already supported in ESP-Matter, ESP-GMF, ESP-BLE-MESH, and ESP-BLE-Audio, along with support for using the chip as a dedicated communications coprocessor linked to a separate microcontroller or microprocessor host via ESP-Hosted and ESP-AT.

More information on the chip is available on the Espressif website; the chips are available in single-unit quantities on the company's official AliExpress store for $4.51, with shipping in mid-August, though low-quantity buyers should be aware there's a hefty $34.24 shipping fee on top.