Renesas’ High Performance MCUs Based on Arm Cortex-M85 Processor

By Taryn Engmark

Associate Editor

Embedded Computing Design

December 11, 2023


Renesas’ High Performance MCUs Based on Arm Cortex-M85 Processor

TOKYO. Renesas Electronics recently introduced its RA8 Series of microcontrollers (MCUs), which provide a performance level of over 3000 CoreMark points, as well as deterministic, low latency, real-time operation. The series' implementation of the Arm Cortex-M85 processor enables 6.39 CoreMark/MHz performance, which will allow system designers to use the RA MCUs in applications that previously required microprocessors (MPUs). The new series is part of Renesas’ popular RA Family of MCUs based on Arm Cortex processors. Existing designs built for other RA devices can easily be ported to the new RA8 MCUs.

Helium Technology for Superior AI Performance

The RA8 Series MCUs deploy Arm Helium technology, Arm’s M-Profile Vector Extension that provides up to a 4x performance boost for digital signal processor (DSP) and machine learning (ML) implementations versus MCUs based on the Arm Cortex-M7 processor. This performance increase enables a potential elimination of an additional DSP in systems for certain applications. Additionally, the RA8 Series MCUs enable edge and endpoint devices to implement natural language processing (NLP) in voice AI and predictive maintenance applications, using Helium to accelerate the neural network processing.

Security Features

The Cortex-M85 core featured in the new MCU series devices includes Arm TrustZone technology, which enables isolation and secure/non-secure partitioning of memory, peripherals, and code. The RA8 Series MCUs introduce the most advanced Renesas Security IP (RSIP-E51A) that provides cryptographic accelerators and supports a true secure boot.

Additional security features include:

  • Immutable storage for a strong hardware Root-of-Trust
  • Octal SPI with Decryption-on-the-fly (DOTF)
  • Secure authenticated debug
  • Secure factory programming and tamper protection

In concert with Arm TrustZone, these features allow comprehensive and fully integrated secure element functionality. The RA8 Series also targets PSA Certified Level 2 + Secure Element (SE), NIST CAVP, and FIPS 140-3 certifications.

Low Power Features

RA8 Series devices integrate low power features and multiple low power modes to improve power efficiency. A combination of low power modes, independent power domains, lower voltage range, fast wakeup time, and low typical active and standby currents enables lower overall system power in accordance with regulatory requirements.

Additional Features of the RA8M1 Group MCUs

  • Memory: Integrated 2MB/1MB Flash memory and 1MB SRAM (including TCM, 512KB ECC protected)
  • Peripherals: xSPI compliant Octal SPI with XIP and decryption-on-the-fly (DOTF), CAN-FD, Ethernet, USBFS/HS, 16-bit camera interface, and I3C, among others
  • Packages: 100/144/176 LQFP, 224 BGA

The new RA8M1 Group MCUs are supported by Renesas’ Flexible Software Package (FSP), which provides all the infrastructure software needed for fast application development, including multiple RTOS, BSP, peripheral drivers, middleware, connectivity, networking, and security stacks, as well as reference software to build complex AI, motor control, and cloud solutions. Customers can also integrate their own legacy code and choice of RTOS with FSP.

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