Renesas MCUs tackle building automation

  • February 12, 2024
  • Steve Rogerson

Japanese electronics company Renesas has introduced a microcontroller family to address real-time control of motors, power supplies and other products commonly used in industrial and building automation, as well as smart homes.

The RA8T1 microcontrollers (MCUs) are based on the Arm Cortex-M85 480MHz processor, and form the third group in the firm’s RA8 series, all of which deliver 6.39 CoreMark/MHz. They use Arm’s Helium technology that provides up to a four-times performance boost for digital signal processor (DSP) and machine-learning (ML) implementations over the Cortex-M7 core. This lets them be used for AI functions that can predict maintenance requirements for motors, reducing downtime.

The devices ( include PWM timing features such as three-phase complementary output, 0% and 100% duty output capability, a double-buffer compare match register, and five phase counting modes. Analogue capabilities include 12bit ADCs, 12bit DACs and high-speed comparators used in voltage and current measurement and over-current protection.

Multiple communications functions include SCI, SPI, I2C, I3C, Can, Can-FD, Ethernet and USB-FS. The port output shutdown capability is for when an anomaly is detected, an important safety feature in motor control. These capabilities combined with the timers and power management help users build comprehensive, low-power motor control.

“Renesas is already the market leader in motor control with the widest MCU portfolio for smart home, building and factory automation systems,” said Daryl Khoo, vice president at Renesas. “The performance of these MCUs is critical in high-speed electric motor control that requires sophisticated algorithms and application software to run in a reliable, safe and secure manner. The RA8T1 MCUs bring unprecedented CPU horsepower to the portfolio along with Helium technology that allows our customers the additional flexibility to deliver smart AI and ML without the need for additional hardware.”

Security includes Arm TrustZone technology, Renesas RSIP-E51A security IP, secure boot with first stage bootloader in immutable storage, and PACBTI pointer authentication and branch target identification security extension.

On memory, they have integrated 2Mbyte and 1Mbyte dual-bank flash and 1Mbyte SRAM including 128kbyte TCM and 512kbyte ECC protected.

They come in 100-, 144- and 176-pin LQFPs and 224-pin BGAs, and are supported by Renesas’ FSP flexible software package (, which enables faster application development by providing all the infrastructure software needed, 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 options. Users can integrate their own legacy code and choice of RTOS with FSP, thus providing flexibility in application development. Using the FSP should ease migration of existing designs to the devices.

The MCUs are supported in Renesas’ flexible motor control development kit that enables evaluation of motor control using permanent magnet synchronous motors (brushless DC motors) and the Renesas motor workbench development tool. This development kit offers a common design platform with numerous motor control MCUs from the RA and RX families, enabling migration of IP across devices.