Renesas adds 32-bit MCUs for industrial & appliance motor control

March 24, 2016 // By Graham Prophet
Renesas Electronics adds the RX24T group of MCUs thatuse its RXv2 CPU core; the MCUs deliver double the performance from the RX23T, 30% reduced development time, and additional instructions designed to accelerate performance and energy efficiency in industrial equipment, office equipment, and household appliances.

Six new devices have pin counts from 80- to 100-pin and on-chip flash memory capacities from 128 kB to 256 kB. The RX24T Group enables simultaneous inverter control of multiple motors with a single chip and are suited for permanent magnet AC (PMAC) motor control.


The RX24T Group offers up to 160 DMIPs, including dedicated analogue functions, increases the arithmetic operation and expands the motor-control peripheral functions of the cost-optimised RX23T.

Renesas plans to deliver a 24-V motor control evaluation kit, that can support both the single-motor control RX23T and the multi-motor control RX24T.


Legal requirements mandating improved motor efficiency have increased demand for highly efficient inverter control; this has been part of the motivation leading to the added MCUs assisting energy efficiency, higher-precision control, reduced board size, and shorter development time of the RX24T Group.


With on-chip FPU functionality for faster code execution, RX24T supports high-performance multi-motor control for development of platforms with a broad range of products. RX24T incorporates the RXv2 CPU core with a five-stage pipeline, a floating point unit and DSP functions, executing 32-bit multiply within a single instruction to improve algorithm calculation accuracy. Effectively, the RX24T running at 80 MHz has similar performance levels of a comparable 100 MHz MCU. The on-chip FPU functionality provides faster implementation of calculation-intensive algorithms with wide dynamic range.


The FPU enables the overall code to be reduced, and overall software implementations are executed much faster as no scaling or saturation occurs. It offers a higher accuracy than the integer implementation as the real physical units are used in the embedded software. The FPU guarantees a faster computation time for PI controllers and estimators. The FPU simplifies debugging and can reduce development time by approximately 30% while reducing the rate of software glitches.


This Group of MCUs maintains compatibility with the RX23T Group, allowing reuse of existing hardware and software assets, boosts CPU performance from