Energy efficiency is becoming more and more important to solve global environmental problems and realize a sustainable society which makes energy-saving technologies ever more important worldwide. Motors often consume the largest amount of power in applications, so we can easily reduce power loss and contribute to energy savings through high-accuracy inverter control.

To achieve this, Renesas has developed two new motor control MCUs in the RA family of 32-bit microcontrollers with Arm core. (Figure 1) The lineup of high-performance solutions and compact packages is best suited for consumer, industrial, and other applications that require high-accuracy inverter control despite system space constraints. The RA4T1 and RA6T3 groups enable lower power consumption in various applications, contribute to lower energy consumption and help improve the global environment.

RA4T1 and RA6T3 MCUs are optimized for a balance of performance, functionality, and price for single inverter control. These are equipped with an Arm Cortex-M33 core operating at up to 200 MHz (100 MHz for RA4T1) with features to realize high-accuracy inverter control, including hardware accelerator trigonometric function unit, 16-bit timer supporting complementary PWM output, 12-bit A/D converter with dedicated 3-channel sample & hold function, as well as programmable gain amplifier and comparator. A safety feature to protect the inverter circuit, a port output enable function, is also provided to shut down the PWM output. USB 2.0 FS Device (RA6T3 only), CAN FD and I3C, among other communication interfaces are included.

Both RA4T1 and RA6T3 groups offer the optimum balance of performance, functionality, and price, and can be used in a wide variety of consumer and industrial inverter control applications. For example, the smallest package of the RA4T1 group is a 5 x 5 mm 32-pin QFN, which is suitable for small power tools. The more powerful RA6T3 group can perform high-speed, real-time control and communication functions simultaneously, making it suitable for applications such as e-bikes, which require motor control and communication with a display panel. These devices are also suitable for applications such as vacuum cleaners, induction cookers, washing machines, fans, pumps, general-purpose inverters, thermal printers, and small robots.

The RA4T1 and RA6T3 evaluation environment includes a choice of integrated development environments, including e² studio, Keil MDK, and IAR EWARM, which can be used for the entire RA family in general. The Flexible Software Package (FSP), which includes BSP, HAL driver, middleware for motor control, and various embedded OSs, is available for developing embedded systems using the RA family. FSP facilitates complex software implementation and contributes to shortening software development time.

We provide MCK-RA4T1 and MCK-RA6T3 motor control development kits for easy evaluation of motor control systems. The kits include a CPU board, inverter board, BLDC motor and sample code as described below. The CPU board alone can be used to evaluate MCU peripheral functions, and since it is equipped with a Pmod connector, it can be connected to a sensor board, wireless communication module or others, providing excellent expandability.

We provide the QE for Motor software development support tool for easy operation of settings, tuning, and analysis required for motor control software development according to the workflow (upper left in Figure 3). It allows efficient configuration of motor middleware and drivers while checking the hierarchical structure diagram (upper right in Figure 3) in conjunction with FSP.

QE for Motor is linked with a motor control development support tool, the Renesas Motor Workbench. This allows motor control signals to be displayed on a PC like an oscilloscope and motor control variables can be updated on the GUI without stopping the motor (Fig. 3, bottom left). In other words, the QE for Motor tool enables software development in a seamless environment and helps shorten development time.

In addition, the following list is sample code for motor control that works with this environment and these application notes. More options will continue to be added in the future.

Application Notes:

• Sensorless vector control with three shunts for permanent magnet synchronous motor
• Sensorless vector control with one shunt for permanent magnet synchronous motor
• Vector control for permanent magnet synchronous motor with encoder
• 120-degree conducting control of permanent magnetic synchronous motor using Hall sensors
• Sensorless 120-degree conducting control of permanent magnetic synchronous motor
• Vector control for permanent magnetic synchronous motor with inductive sensor

We highly recommend trying out the development kits MCK-RA4T1, MCK-RA6T3 and the motor control software development support tool QE for Motor. We are confident you will appreciate the user-friendliness of these development environments and see for yourself that the RA4T1 and RA6T3 MCUs excel in motor control systems. Let us know your experience working with the tools.

Winning Combination Solutions

To further simplify motor control development, we also offer Winning Combination solutions that use complementary Renesas products, such as gate driver and power supply ICs.

• High Power, Compact BLDC Motor Control
• E-bike System Solution
• Digital Power Conversion with Totem Pole Interleaved PFC

In addition to Arm core-based MCUs, Renesas also provides different platform options to support a wide variety of motor control applications. The RISC-V ASSP MCUs provide a complete solution for users developing on RISC-V platform. Pre-developed application software is programmed on the device at factory production, with specialized application code developed by IDHs (independent design houses) enabling users to add sophisticated field-oriented motor control functionality without any effort in terms of development, testing and validation of the implementation.

In addition, the RX26T MCU is ideal for users developing on the proprietary Renesas platform. Using the same motor control kit as RA MCUs, users can easily scale development across different platforms.