Japanese electronics giant Renesas has introduced microcontrollers that make it easier to implement firmware over-the-air (FOTA) updates for smart energy management, building automation, medical devices, consumer electronics and other IoT applications.

The RA2A2 microcontrollers (MCUs) are based on the Arm Cortex-M23 48MHz processor. The low-power devices have a 24bit sigma-delta analogue-to-digital converter, dual-bank code flash and bank swap function for FOTA updates.

The devices offer multiple power structures and voltage detection hardware to realise energy-efficient, low power operation down to 100µA/MHz in active mode and 0.4µA in software standby mode. An independent power supply real-time clock extends battery life for applications requiring long lifetime management in extreme conditions. The MCUs also offer AES hardware acceleration, high-precision (±1.0%), high-speed on-chip oscillator, temperature sensor and operating voltage from 1.6 to 5.5V.

The MCUs contribute to the digitalisation of conventional systems with features including high-level analogue sensing, FOTA support, 8kHz/4kHz hybrid sampling, and AES hardware accelerator functions. When the end-systems are digitalised, it is possible to analyse individual systems status seamlessly for further energy-efficient, streamlining operation.

For example, smart electricity meters with non-intrusive load management (NILM) technology enable energy consumption monitoring based on detailed analysis of the current and voltage of the total load. The adoption of smart meters with NILM is said to be the most cost-effective and scalable method for increasing energy efficiency and lowering energy consumption.

“Renesas has worked closely with our customers to understand their requirements for next-generation systems that can support critical energy conservation goals,” said Akihiro Kuroda, vice president at Renesas. “The RA2A2 group MCUs are the result of that collaboration coupled with our world-leading technical expertise. We are proud to provide this that will enable significant energy savings in a wide array of systems.”

The devices have 512kbyte integrated, dual-bank flash memory and 48kbyte SRAM. Analogue peripherals include 24bit sigma-delta ADC with digital filter, 12bit ADC, and temperature sensor. They come in 100-, 80- and 64-pin LFQFPs.

The MCUs are supported by Renesas’ FSP flexible software package (www.renesas.com/us/en/software-tool/flexible-software-package-fsp) that 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 offerings. Users can integrate their own legacy code and choice of RTOS with FSP, thus providing flexibility in application development.

The MCUs (renesas.com/RA2A2) are available now, along with the FSP software and the RA2A2 evaluation kit. Samples and kits can be ordered either on the Renesas web site (www.renesas.com) or through distributors.