Renesas' RX700 MCU offers 240-MHz, run-from-flash operation

February 26, 2015 // By Graham Prophet
The RX700 microcontroller series expands the 32-Bit RX family to with a part that has 240 MHz operation, security features and 4 MB of memory: a combination that Renesas presents as an increase in productivity and security for industrial connected-device applications

The RX71M Group is the new flagship product in the RX Family of 32-bit microcontrollers (MCUs). Developed for use in industrial equipment, the new series doubles the CPU operating frequency to 240 MHz from the 120 MHz of previous products and is available with up to 4 MB of on-chip flash memory. The flash memory is built in Renesas' own MONOS, 40-nm process which achieves 8-nsec access times, four times faster than alternative technologies, and with long endurance and reliability.

On-chip flash memory MCUs, Renesas notes, are extensively used in midrange industrial equipment to achieve a good balance between performance and system cost. M2M communication in industrial equipment has created demand for MCUs that are optimised for a range of performance levels, from sensor nodes operating at around 30 MHz to controllers operating at 200 MHz and above, and also for scalability in order to reduce the man-hours required for software and hardware development.

Renesas finds that industrial customers are increasingly dispersing their system development efforts among multiple facilities and pursuing joint development arrangements with partners with strengths in specific technologies. This will result in reduced development costs of the new and advanced functions associated with transitioning to the IoT while increasing efficiencies and reducing development times. Such dispersed development and joint development approaches could bring risks to the customer’s own core technologies (such as important algorithms) such as leaks or unauthorised duplication. Software resources must be protected.

Industrial equipment demands real-time performance. When an MCU’s CPU operating speed is faster than the speed at which the flash memory can be accessed, dedicated high-speed on-chip SRAM can be added so that algorithms that require real-time processing can be run from the high-speed SRAM, but using dedicated SRAM in addition to the on-chip flash memory increases the cost. Where the on-chip memory capacity of previous flash microcontrollers was inadequate, it was necessary to add expensive high-speed SRAM or flash memory externally,