Renesas Unveils Over 35 New Motor Control MCUs

In today's fast-paced world, motor control plays a pivotal role in an array of industries, from robotics and automation to automotive and aerospace applications. The ability to precisely manipulate motors, including achieving a desired speed, position, and torque, is essential for optimal performance and efficiency. To make this a reality, microcontrollers (MCUs) often serve as an integral part of the equation.

 

The new Renesas motor control MCUs are aimed at applications ranging from home appliances to industrial robots.

 

With an understanding of this, semiconductor companies have started designing MCUs specifically for motor control purposes. This week, Renesas added to the market with the release of over 35 new MCUs designed explicitly for motor control applications.

In this article, we’ll take a look at what makes an MCU well-suited for motor control and some of the details of Renesas’ new releases. 

 

MCUs for Motor Control

Broadly, motor control systems vary in complexity and requirements, ranging from simple power engagement to more advanced functions like speed and position control. As part of this, these systems need to address issues such as inductive behavior, sudden load changes, and unexpected current draws. Hence, to meet these demands, motor control often requires the use of an MCU, which can offer intelligent functionality for controlling motors.

Most common microcontrollers already possess standard features such as I/O, timers, ADCs, and DACs that can be utilized for motor control. In most cases it is important to note that external drivers are typically necessary for MCU motor control, as MCU I/O lines lack the necessary drive capabilities to directly control motor lines.

Certain microcontrollers, however, offer additional features that enhance their motor control capabilities. 

 

Example application of a 3-phase sensorless brushless DC (BLDC) motor control system using an RA4t1 MCU.

 

One such feature might be an integrated analog comparator which would allow an MCU to quickly respond to threshold exceedances. These MCUs will also often be designed to have quick interrupt response times and efficient wake-up times to rapidly intervene when thresholds are exceeded. Here, a motor control-specific MCU would have the ability to generate interrupts and outperform general-purpose MCUs that would otherwise rely on periodic polling using ADC stages.

Another feature that is standard in motor control-specific MCUs is fast and accurate ADCs. These components prove especially valuable for monitoring and verifying normal motor operating conditions. Additionally, well-performing DACs or PWM modules are often integrated into MCUs for variable-voltage drive motors, enabling control over torque and speed. 

 

Renesas’ Motor Control MCUs

This week, Renesas added to the market of motor control-specific MCUs with the announcement of over 35 new products. These 35 MCU offerings all come from one of three families: the RA4T1 Group, the RA6T3 Group, or the RX26T Group.

 

Features of the RA6T3 family

 

• The RA4T1 Group: a family of MCUs for motor control built around an 100 MHz Arm Cortex-M33 core. Within the family, you can find offerings with specs such as code flash memory ranging from 128 KB to 256 KB, 4 KB of data flash memory, and 40 KB of SRAM. The RA4T1 Group also offers an optimized peripheral for motor control and inverter control functions and comes in a 32-pin QFN and LQFP package options.
   
• The RA6T3 Group: a group of MCUs that is designed to deliver a balance between peripheral functions and cost for motor control. Built on a 200 MHz Arm Core, the RA6T3 Group features 256 KB of code flash memory, 4 KB of data flash memory, and 40 KB of SRAM. According to Renesas, this group is best used for motor control and inverter control applications requiring high performance.
   
• The RX26T Group: a group of motor control-optimized MCUs that are designed for high noise immunity and control accuracy. Products in this group are designed to be compatible with 5V rails and support dual-motor control via Field Oriented Control (FOC) and Power Factor Correction (PFC) control integrated onto the chip. The RX62T products are built around a 120MHz, 32-bit RX MCU supported by up to 512 KB flash memory, up to 64 KB SRAM, and 16 KB data flash memory.

Between the 35+ offerings coming out of these groups, Renesas hopes to provide a motor control solution for just about anybody. 

 

All images used courtesy of Renesas Electronics