NXP has introduced the MCX A5 family of Cortex-M33 MCUs, which features a 10/100Mbps Ethernet MAC and an integrated 10BASE-T1S Single Pair Ethernet digital PHY. It targets industrial and networking applications such as controllers, PLCs, remote I/O, building and energy management systems, and other connected edge devices.
The MCUs run at up to 240 MHz and feature up to 2 MB dual-bank Flash and 640 KB SRAM, along with multiple communication interfaces and analog peripherals. Security features include an EdgeLock accelerator, secure boot with PQC hybrid support, secure firmware updates, lifecycle management, secure debug, external Flash encryption, and anti-tamper monitoring.
NXP MCX A5 Series (MCXA577) specifications:
MCU Core
Arm Cortex-M33 core clocked at up to 240 MHz
Includes FPU, DSP, MPU, and TrustZone support
Integrated SmartDMA co-processor for efficient data handling
Delivers 988.8 CoreMark (4.12 CoreMark/MHz)
Memory and Storage
Up to 2 MB dual-bank Flash with ECC and read-while-write support
16 KB cache engine
Up to 640 KB SRAM, configurable as up to 64 KB RAM with ECC
24 KB RAM retained down to VBAT mode
ROM for Secure Boot
FlexSPI interface for external memory with cache
Networking
Up to 1x 10/100Mbps Ethernet MAC (supports MII / RMII / Ethernet depending on configuration)
Up to 1x 10BASE-T1S Digital PHY
Peripherals
Up to 134x GPIOs, with up to 4x high-drive 20 mA I/Os
USB – USB High-Speed (HS) Host/Device with an on-chip HS PHY
Low-speed I/Os
Up to 6x LPUART, 6x LPSPI, and 5x LPI2C
Up to 2x CAN FD interfaces
Up to 4x I3C interfaces
eSPI
Analog peripherals
Up to 2x 16-bit ADCs and up to 2x 12-bit DACs
1x LPCMP (Analog comparator)
Integrated voltage reference (VREF) and temperature sensor
Timers and DMA
Up to 5x 32-bit timers and 2x DMA
Low-power timer, Wake timer, Micro-tick timer, OS event timer
RTC
2x Windowed watchdog timers
Frequency measurement and PWM / event timing resources
HMI – TSI (Touch Sensing Input) and FlexIO interfaces
Security
EdgeLock accelerator with TRNG, PKC (ECC, RSA), and SGI (AES256, SHA-2, PQC, KeyStore)
Secure boot (with PQC hybrid support), secure firmware update, secure debug, and lifecycle management
Targets PSA Level 3 and SESIP Level 3 certifications
Code Watchdog, Glikey-protected access s, and passive anti-tamper detection to defend against physical and software attacks
Power
Operating voltage – 1.7V to 3.6V
1.2 V independent I/O supply support
Power management system with POR/LVD/HVD and LDO
Multiple low-power modes with wake-up sources down to deep power-down mode
Packages – WFBGA169, LQFP144, and LQFP100
Operating junction temperature – -40°C to 125°C
At the time of writing, NXP lists four SKUs, of which three MCXA577 variants offer the same 240 MHz core, memory, Ethernet, and CAN FD features, and differ mainly in package and GPIO count. The MCXA557VPN keeps the same core and memory but removes the Ethernet MAC, 10BASE-T1S DPHY, and CAN FD.
In terms of software support, the company says the MCXA5 family is supported by NXP’s MCUXpresso ecosystem, which includes SDKs, middleware, security software, Visual Studio Code integration, and LTS software releases. NXP also plans support for the Zephyr RTOS, while selected devices are planned to support Rust.
To simplify development, NXP offers the FRDM-MCXA577 development board for evaluating the MCX A5 family. It is based on the MCXA577 and includes an onboard MCU-Link Lite debugger, standard headers, and support for Arduino, mikroBUS, and Pmod expansion boards. However, detailed information about the board is still limited. While looking for more details, I found a dedicated documentation page for the FRDM-MCXA577 dev board that lists support for FreeRTOS, MCUboot, FatFs, FreeMASTER, and Trusted Firmware-M, along with the MCXA577 driver API. I also found the FRDM-MCXA577 on the Zephyr Project, where support appears to still be under development. As the support pages are still under development, you may notice that different pages use different images, which can be a little confusing. Just a heads-up in case you run into the same issue.
NXP first introduced its MCX family of general-purpose Arm MCUs in 2022. The company later added the cost-optimized MCX A14x/A15x Cortex-M33 MCUs in 2024 and the mixed-signal MCX A34 with a Math Acceleration Unit in 2025, along with the MCX L, MCX W, and E series.
Four SKUs: MCXA577VPN, MCXA577VLQ, MCXA577VLL, MCXA557VPN
The new MCX A5 extends the A-series with wired industrial connectivity, including an integrated 10BASE-T1S digital PHY, topology discovery, and post-quantum cryptography. Normally, adding 10BASE-T1S would require an external PMD such as the NXP TJF1410 or Microchip LAN867x/LAN865x Single Pair Ethernet MAC-PHY, along with a separate host MCU. However, the MCX A5 brings these functions into a single MCU and targets industrial edge nodes using interfaces such as RS-485, CAN, or Ethernet.
The MCX A5 family is sampling now, and NXP mentions general availability is expected in Q4 2026. The FRDM-MCXA577 board does not appear to be available at the time of writing. More information about the MCU is available on its product page and in the press release.
Debashis Das is a technical content writer and embedded engineer with over five years of experience in the industry. With expertise in Embedded C, PCB Design, and SEO optimization, he effectively blends difficult technical topics with clear communication
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