How to Select an MCU for Motor Control

Introduction

The microcontroller is a central component in many motor-control systems. It processes feedback signals, generates PWM outputs, manages communication and responds to operating faults. Selecting the correct MCU requires matching its processing capability and peripherals to the motor type and control method.

Define the Motor and Control Method

Start by identifying the motor type, operating voltage, speed range and required control method. Brushed DC, brushless DC, permanent-magnet synchronous and induction motors can require different processing, sensing and PWM capabilities.

Evaluate Processing Performance

The MCU must complete control calculations within the required control-loop period. Field-oriented control and sensorless algorithms may require higher processor performance than basic speed or position control. Engineers should also consider future firmware features and system expansion.

Review PWM and Timer Capabilities

Motor control depends on accurate and synchronized PWM signals. Review the number of timer channels, resolution, dead-time control and fault-input support. The MCU should provide enough flexibility to control the required inverter or motor-driver configuration.

Check ADC and Current-Sensing Support

Current and voltage measurements must be synchronized with PWM timing to reduce noise and improve control accuracy. ADC conversion speed, trigger options and channel count should match the sensing architecture. Built-in comparators or fault inputs can provide faster hardware-level protection.

Consider Memory and Communication

Flash, RAM and communication interfaces should support the complete system, including control software, diagnostics and external devices. Common interface requirements may include CAN, UART, SPI and I2C.

Product Selection

Toshiba offers microcontroller families for motor control and other embedded applications. Review available MCU series and supporting tools on the Toshiba microcontrollers product page.