"Achieving driving range and charging speed targets requires a critical role for the MCU."

In-Vehicle MCU Application Potential is Growing Rapidly

“The requirements for electronic components in electronic control units, particularly MCUs and high-voltage switches (MOSFETs), are becoming increasingly demanding in terms of processing power, security, power efficiency, and connectivity.”

As electrification and electrification of internal combustion engine vehicles accelerate and the era of electric vehicles arrives, interest in MCUs and motor control is increasing. Yan Goh, Senior Marketing Manager for Automotive at Microchip Technology, was interviewed about the development trends of automotive motor control MCUs.

■ As vehicle electrical systems move toward centralized development, can the role of the MCU be gradually reduced or replaced?

The automobile industry is currently undergoing a huge change called 'electrification'. And manufacturers are also aiming to develop and redesign next-generation electrical systems in line with this trend.

The electrical systems of electric vehicles (EVs) encompass a wide range of functions, from high-voltage systems to low-voltage systems. In EVs, high-voltage systems typically include electronic control units (ECUs) for the on-board control circuit (OBC), DC-DC, traction motor, HVAC inverter, and BMS systems. The requirements for the electronics in these ECUs, particularly MCUs and high-voltage switches (MOSFETs), are becoming increasingly demanding in terms of processing power, security, power efficiency, and connectivity. Meanwhile, centralized low-voltage electrical systems, often referred to as "centralized computing modules," are used to support vehicle control, including body applications, autonomous driving, and human-machine interfaces.

While this central computing is increasingly acting as a single, overarching "brain" in vehicles, it's only a small part of the equation. OEMs envision partitioning vehicle control from traditional domain control into a zonal architecture, leveraging the central computing as the primary backbone and high-speed Ethernet communications as the primary connectivity. This type of architecture will likely create even more opportunities for Microchip, as the demand for MCUs within the overall zonal architecture increases to ensure scalability and flexibility while reducing complexity.

■ Numerous MCU applications are being applied in automobiles. Can the motor control field be considered the field with the greatest growth potential and added value?

Microchip has been providing automotive semiconductor solutions for the past 20 years. As the automotive market shifts toward electrification and autonomous driving, Microchip sees tremendous growth potential as a key player in these applications. Microchip's automotive solutions, including MCUs, in-vehicle communications, and human-machine interfaces, have been chosen by many automotive suppliers.

In EVs, most modules and functions, including the aforementioned electrical control, require MCUs. Human-machine interfaces (HMIs) for things like steering wheel switches, lighting buttons, seat position adjustment buttons, and all the terminal nodes for in-vehicle cables require processing modules powered by MCUs. Motor control is just one of many in-vehicle applications that require MCUs to perform specific functions. The potential for new MCU applications in automobiles is rapidly growing along with the increasing number of motors per vehicle.

■ As electric vehicles gain popularity, motor development has also accelerated. The technical challenges that motor control MCUs may face are:

From an EV OEM's perspective, all challenges stem from the goal of increasing maximum driving range per charge or accelerating battery charging to enhance the driver experience. Achieving these two seemingly simple goals requires the critical role of numerous electronic components, particularly MCUs.

Microchip is investing in automotive electronics solutions to maximize power efficiency and reduce development times. For example, Microchip offers dedicated power microcontrollers, combined with high-voltage SiC MOSFET transistor-diode technology, to reduce the complexity associated with the high-voltage, fast-charging, and high-efficiency requirements of electric vehicles. This technology enables suppliers to achieve high efficiency ratings while reducing development time.

■ Automakers are focusing a lot of attention on semiconductor development. It seems likely that there will be changes in the development methods for motor control MCUs as well.

As the semiconductor shortage continues, automotive OEMs are also experiencing production disruptions. Consequently, OEMs are showing greater interest than ever before in the semiconductors used in their products. In the automotive industry, collaboration among OEMs, Tier 1 and Tier 2 suppliers, and semiconductor suppliers is essential to ensuring a positive automotive experience for end consumers. For this reason, Microchip, as a leading global supplier of MCUs, values customer technical feedback during the new product development process.

In the automotive motor control field, many existing body applications are transitioning from low-efficiency 2-phase BDC motors to high-efficiency 3-phase BLDC or PMSM motors. This transition utilizes control algorithms that reduce audible motor noise, improving the customer experience. Most motor control applications used in internal combustion engine vehicles also apply to EVs, as most motors are used for non-engine functions, namely body and interior functions.

EVs have created several new opportunities in motor control, including the need for traction motor control. Belt- or engine-driven accessories have been replaced by electric motors, and several new pump applications are required for battery and inverter cooling. Furthermore, the control of multiple motors and valves for systems such as cooling and thermal management is being integrated into a single motor controller, as exemplified by the dsPIC33CH dual-core DSC. This integration allows for reductions in component costs and space requirements by eliminating multiple PCBs.