Next-generation automotive microcontrollers: STMicroelectronics technology analysis

STMicroelectronics (ST) has been deeply involved in the automotive market for more than 30 years, and its products and solutions cover most application systems in ordinary vehicles. With the development of the market, STMicroelectronics' products are also constantly upgraded and improved, and its important product, automotive microcontrollers (MCUs), are no exception.

ST pioneered embedded non-volatile memory (eNVM) and led the market with ST10, followed by the SPC5 series of automotive microcontrollers based on the PowerPC architecture, with more than one billion MCUs shipped in the automotive field. Cost-effective automotive controllers from the STM8 series complement this product line.

ST's Stellar product family

The Stellar product family is STMicroelectronics' latest generation of Arm-based automotive microcontrollers, and is STMicroelectronics' first automotive MCU portfolio that covers both high-end and low-end products. These advanced microcontrollers reduce development complexity, ensure application security and reliability, and enable next-generation vehicle architectures and functions to have better performance and energy efficiency. Customers can benefit from shorter development times and focus on bringing innovation and differentiation to their software-defined vehicles (SDVs) to cope with fierce market competition. As a result, Stellar products are gaining increasing attention among Asian and European customers.

Stellar is the industry's first embedded non-volatile memory technology after eFlash, and represents the most mature and smallest automotive-grade storage unit solution on the market. The Stellar product family is suitable for automotive electrification applications, including X-in-1 highly integrated vehicle motor control computers, new vehicle architectures, and safety MCUs for safety-critical subsystems such as ADAS, regional control, and body integration.

It fully supports automotive transformation by safely integrating multiple functions into a single device and allowing continuous integration of new functions in the vehicle. All this is inseparable from key technologies, including the right choice of processor core technology, virtualization, Ethernet support, and breakthrough memory technology embedded in automotive MCUs. This technology is a disruptive change for customers facing application memory size challenges.

Stellar MCU is equipped with Arm® Cortex®-R52+ processor technology. This high-performance processor supports real-time virtualization and is suitable for real-time control safety systems, and can run multiple applications simultaneously without interfering with each other. The microcontroller has a fully programmable auxiliary core that can accelerate the execution of specific functions, such as routing, low-power management and digital filtering, while reducing the computational workload of the main core.

“As the driving experience continues to evolve in the era of AI and software-defined cars, it is critical to improve functional safety, flexibility and real-time performance in vehicles,” said Dipti Vachani, senior vice president and general manager of the automotive line of business at Arm. “The Stellar microcontroller family built on Arm leverages the advanced safety and real-time capabilities of the Arm compute platform, along with the broad Arm software ecosystem, enabling automakers to implement innovative features and stay ahead of the curve in the automotive space while complying with stringent safety regulations.”

Stellar microcontrollers enable automakers to introduce Ethernet capabilities in vehicles and are STMicroelectronics' first MCUs with embedded Ethernet switches. Ethernet technology can improve the energy efficiency and flexibility of data exchange, support gigabit throughput requirements, and provide a higher level of security. By supporting various in-vehicle communication topologies, such as Ethernet rings, this automotive microcontroller fulfills the promise of reducing the length and manufacturing cost of vehicle wiring cables by half.

Phase Change Memory Will Redefine What's Possible in Vehicle Software

Stellar microcontrollers revolutionize the software update over-the-air (OTA) experience by leveraging embedded phase change memory (PCM) technology and its flexibility. In the automotive industry, OTA is essential for adding new features and security patches without disassembling the hardware. However, this flexibility often requires careful consideration of future storage capacity requirements, as over-the-air updates can lead to increased costs and complex product planning.

STMicroelectronics' innovative PCM is not just any memory. It is not only the industry's smallest automotive MCU memory unit, but also the first groundbreaking technology breakthrough in the automotive field, redefining what functions can be achieved by vehicle software. STMicroelectronics' PCM innovation takes the memory's ability to process data to a higher level. This is not only about the read and write performance of the memory, but also a forward-looking solution that brings adaptability and lasting value to the automotive field, allowing end developers to continuously improve and upgrade automotive functions.

As vehicles become increasingly software-defined, the ability to introduce new and improved features becomes critical. PCM’s breakthrough technology supports the transition to more adaptable, future-proof vehicles, giving automakers new ways to optimize the experience as vehicle functionality continues to improve.

In addition, PCM also provides support for uninterrupted OTA updates. PCM can safely store software updates without affecting the current operation of the vehicle. Thanks to the parallel read and write capabilities, the download of new software will not interfere with the application code currently running on the MCU, thus ensuring that the update process continues to use the car.

The Stellar P series is used to integrate multiple functions, while the Stellar G series is used to implement regional controllers for software-defined vehicles (SDVs). Both series utilize STMicroelectronics' internally developed eNVM memory and 28nm FD-SOI technology, which can achieve higher frequencies at lower power consumption and have stronger radiation resistance. Stellar is the first 28nm product to obtain functional safety certification and will be put into production before the end of the year.

The Stellar product family also supports the growing X-in-1 high integration trend, advancing the decisive shift from gasoline vehicles to electric vehicles and promoting the development of more affordable electric vehicles. X-in-1 powertrain solutions integrate multiple components into a single ECU, enabling manufacturers to create energy-efficient, compact and cost-effective vehicles.

Stellar provides scalable X-in-1 high integration solutions, from low integration to high integration ECUs, and the microcontroller can integrate more and more ECUs. The solution supports the development of increasingly complex X-in-1 systems by providing enhanced cores, analog components, and I/O ports.

Wang Mingwang, founder of Sunwoda, said: "As a global leader in lithium-ion batteries, Sunwoda provides stable and reliable automotive electronic system solutions to global automotive suppliers. Our new collaboration with STMicroelectronics focuses on developing solutions using ST's advanced Stellar microcontrollers and proprietary production processes, mainly including battery management systems as well as VDC/regional and body control functions. Our common goal is to provide intelligent solutions to improve the next generation of new energy vehicles in China and around the world."

Basic components of Stellar MCU:

1. Arm® Cortex®-R52+ technology: capable of running multiple applications simultaneously in real time without interfering with each other.

2. FD-SOI technology: achieves higher frequencies at lower power consumption and enhances radiation resistance.

3. New, powerful wireless download method and true EEPROM function.

4. A range of Ethernet-related intellectual property rights (MAC, MACSec, switches) that support high-capacity data transmission, enable different in-vehicle communication topologies, and reduce vehicle manufacturing costs.

5. Fully programmable auxiliary cores: Accelerate specific functions, such as routing, low-power management and digital filtering, while offloading the main core.

STM32 microcontrollers will enter the automotive market

As part of an expanded deployment of its automotive microcontroller (MCU) strategy, STMicroelectronics will bring the general-purpose STM32 microcontroller platform to the automotive industry. The STM32 platform is widely recognized for its cost advantages, simplicity, and reliability. With the addition of automotive-grade quality and safety, the STM32A will meet ASIL B standards. From very simple functions to more complex single tasks, the platform can handle a variety of edge actuator applications at an optimized cost, making it particularly suitable for motor control applications in vehicle systems, including windows, mirrors, and sunroofs.

The best combination of industry and automobile: towards a converged future

Over time, the convergence of industrial and automotive hardware and software platforms will combine the strengths of both. The automotive industry brings strong security expertise, while the industrial sector is built on strong IoT and AI solutions. The future convergence will share hardware technology, cores, and a common ecosystem of tools and software support. This convergence will enable customers to seamlessly transition between solutions, providing simplification and full scalability to innovate faster.

Edge AI technology is an example of how ST sees existing industrial technology being applied to the future automotive industry. Neural accelerator development tools enable developers to easily implement AI in their applications, regardless of their level of data science expertise. In the future, neural accelerator technology and its related tools will improve automotive systems. Safety is another application area where ST sees significant benefits from the convergence of industrial and automotive technologies. Over the past 10 years or so, STMicroelectronics has invested in the development of microcontrollers, smart sensors, and AI software tools to meet customer needs and take advantage of edge AI.