NuMicro^® M55 Family Microcontroller Product Line Overview

High-Performance Arm^® Cortex^®-M55 with Vector Acceleration

The NuMicro^® M55 Family is a high-performance microcontroller product line based on the Arm^® Cortex^®-M55 core, operating at up to 220 MHz. It features the Arm^® Helium™ vector processing extension (M-Profile Vector Extension), significantly enhancing capabilities in digital signal processing, edge computing, and machine learning.
The M55 Family integrates the Arm^® Ethos™-U55 Neural Processing Unit (NPU), delivering up to 110 GOPS of AI inference performance—ideal for use cases such as intelligent recognition, sound event detection, image classification, and sensor fusion in AI applications.

The M55 Family includes 1.5 MB SRAM and 2 MB Flash Memory, and support memory expansion via HyperRAM and OctoSPI, offering flexible data processing capacity. The M55 Family is well-suited for real-time control, audio processing, smart sensing, industrial automation, and AIoT deployments—especially in power-constrained environments requiring efficient AI capability.

Rich Peripherals and Low Power Design

The M55 Family integrates comprehensive communication and peripheral interfaces, including Ethernet MAC, USB High-Speed OTG, Full-Speed OTG, CAN FD, I3C, UART, SPI, I²C, QSPI, SmartCard, SDIO, DMIC, CCAP, and PSIO. It supports multiple embedded operating systems such as Zephyr, FreeRTOS, and RT-Thread, making it compatible with a wide range of industrial and embedded networking applications.

In terms of power efficiency, the M55 Family offers five low-power modes, with standby current as low as 2 μA (with RTC on). It supports SRAM retention, low-power ADC, and peripherals such as LPUART, LPI²C, and LPSPI, making it ideal for battery-powered and energy-sensitive devices.

All models are equipped with robust security mechanisms, including Arm TrustZone®, Secure Boot, True Random Number Generator (TRNG), AES-256/ECC-571/RSA-4096 crypto engines, XOM (eXecute-Only Memory), and PSA Certified™ Level 2 compliance, making them a secure choice for trusted embedded systems.

• M55M1 Endpoint AI Series: AI Microcontroller with Built-in Ethos-U55 NPU

The M55M1 is Nuvoton’s flagship AI MCU designed specifically for Endpoint AI applications. It integrates the Arm Ethos-U55 NPU, offering up to 110 GOPS of inference performance tailored for acceleration of machine learning models in vision, audio, and sensor-based tasks. It supports development frameworks including TensorFlow Lite Micro and NuML Tool, enabling fast AI development and deployment.

Despite its powerful AI capability, the M55M1 maintains ultra-low power consumption and does not require external DDR memory, making it suitable for real-time inference, human-machine interaction, smart voice control, and on-device data filtering at the edge. In addition to its NPU, it features full Helium DSP support, USB PD, HyperRAM interface, and advanced security, offering a cutting-edge dual-engine “MCU + NPU” solution for edge AI computing.

• M5531 Vector Extension Series: High-Performance Industrial IoT & Networked Control

The M5531 Vector Extension Series is optimized for high-throughput vector processing and rich industrial networking. Designed for IIoT, industrial control, sensor fusion, and real-time data processing, it features a dual-vector acceleration architecture with Helium DSP and FPU, large 1.5 MB on-chip SRAM, and HyperBus interface for external memory expansion.

It integrates a wide array of connectivity interfaces including 10/100 Ethernet MAC, HS USB OTG with Power Delivery, FS USB OTG, dual CAN FD, I3C, 10x UART, SmartCard, DMIC, CCAP, and more—making it suitable for large-scale industrial automation and edge node applications. Built-in security features are compliant with PSA Level 2, making the M5531 a robust and reliable MCU for secure and connected industrial systems.