Japanese electronics giant Renesas used last week’s Embedded World in Nuremberg to launch a microcontroller series aimed at power-constrained IoT applications.

The RA0 microcontroller (MCU) series is based on the Arm Cortex-M23 processor and is said to offer the industry’s lowest overall power consumption for general purpose 32bit MCUs.

“This is at the low end of the RA line,” said Séraphin Sepa Bikek, business development manager at Renesas. “It makes it easier to migrate from 16 to 32bit. The customer doesn’t need to add external components.”

The RA0 devices consume 84.3μA/MHz of current in active mode and 0.82mA in sleep mode. A software standby mode reduces power consumption by a further 99 per cent to 0.2µA. Coupled with a fast wake-up high-speed on-chip oscillator, these MCUs suit applications in battery-operated consumer electronics devices, small appliances, industrial system control and building automation.

“This is for all sorts of sensor application,” said Bikek, “such as in industrial, consumer appliances and healthcare. We make it very easy to use. Customers can use existing tools to speed up development time.”

Renesas is shipping the first group in the series, the RA0E1 group. These devices have a feature set optimised for cost-sensitive applications. They offer an operating voltage from 1.6 to 5.5V so users don’t need a level shifter or regulator in 5V systems. The MCUs also integrate timers, serial communications, analogue functions, safety functions and HMI functionality to reduce costs. Various packaging options are available, including a 3 by 3mm 16-lead QFN.

“This is the first device in the series,” said Bikek. “We are going to extend the roadmap with more devices next year and the year after.”

In addition, the new MCU’s ±1.0% precision on-chip oscillator improves baud rate accuracy and enables designers to forego a standalone oscillator. It maintains this precision in environments from -40 to +105˚C.

Critical diagnostic safety functions are included as well as an IEC60730 self-test library. Security features include true random number generator and AES libraries for IoT applications, including encryption.

The MCUs (www.renesas.com/us/en/products/microcontrollers-microprocessors/ra-cortex-m-mcus/ra0e1-32mhz-arm-cortex-m23-entry-level-ultra-low-power-general-purpose-microcontroller) are supported by a flexible software package (www.renesas.com/us/en/software-tool/flexible-software-package-fsp) that speeds application development by providing infrastructure software, 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 the FSP.