Designer’s guide: Automotive processors

The automotive industry is a rapidly growing sector that demands high-performance and reliable processors to enable various applications, such as infotainment systems, advanced driver-assistance systems (ADAS), autonomous driving and more. Three main types of processors are at the core of many automotive applications: microprocessors (MPUs), microcontrollers (MCUs) and systems-on-chip (SoCs).

MPUs are the brains of many embedded systems, including automotive applications. They typically contain a single central processing unit (CPU) and offer high performance and flexibility. MPUs are ideal for applications that require significant computing power, such as infotainment systems and ADAS. The automotive industry uses MPUs for image processing, machine learning and other complex algorithms. The most popular MPUs used in automotive applications include the Arm Cortex-A series, Intel Atom and Nvidia Tegra.

MCUs are integrated circuits that contain a processor core, memory and peripherals like input/output interfaces, timers and analog-to-digital converters. MCUs are designed for low-power and real-time applications, making them suited for automotive systems that require precise control, such as engine management and safety systems. MCUs are also used in automotive applications that require connectivity, such as Bluetooth, Wi-Fi and CAN bus. The most popular MCUs used in automotive applications include the Arm Cortex-M series, Renesas RH850 family and STMicroelectronics STM32 series.

SoCs are highly integrated processors that combine multiple components into a single chip, including CPUs, GPUs, memory and I/O interfaces. SoCs are designed to deliver high performance and low power consumption, targeting automotive applications like ADAS and autonomous driving. SoCs are also used in infotainment systems and connectivity applications. The most popular SoCs used in automotive applications include the Nvidia DRIVE family, Qualcomm Snapdragon Automotive, Renesas R-Car family and Texas Instruments Jacinto.

Figure 1: Processors are used in a variety of automotive applications, from infotainment systems to advanced driver-assistance systems. (Source: Shutterstock)

Choosing an automotive processor

When selecting a processor for an automotive application, there are several factors to consider, including power consumption, performance, temperature range and the availability of development tools and software support. It is also essential to consider the reliability and safety of the processor, as automotive applications demand high levels of quality, durability and compliance with strict standards requirements.

These factors include:

• Performance: One of the most critical factors in selecting a processor for automotive applications is performance. Advanced applications like ADAS and autonomous driving require high processing power to execute complex algorithms and tasks in real time. The processor must handle multiple tasks simultaneously, quickly process large amounts of data and deliver high-performance computing capabilities.
• Power consumption: Another critical factor in selecting a processor for automotive applications is power consumption. The processor must consume minimal power to meet the requirements of the automotive application. Low power consumption is crucial to reduce the thermal output, which can cause problems like overheating, and to extend the battery life in electric and hybrid vehicles.
• Temperature range: The automotive environment is harsh and requires a processor that can operate efficiently over a wide temperature range. Temperature variations can cause significant issues with the system’s reliability and performance, and the processor must be capable of withstanding these conditions to ensure safe and reliable operation.
• Reliability: Automotive applications require processors that are reliable and durable. The processor must withstand high vibration and shock and operate in harsh environments with minimal maintenance. The reliability of the processor is critical to ensure the vehicle’s safe operation and avoid any potential safety hazards.
• Safety: Advanced automotive applications like ADAS and autonomous driving require processors designed to meet specific safety standards. The processor must be capable of performing safety-critical functions like emergency braking, lane-keeping and object detection in real time. Safety is a critical factor that must be considered when selecting a processor for advanced automotive applications.
• Connectivity: Automotive applications require processors that can support a range of connectivity options, including Bluetooth, Wi-Fi and CAN bus. The processor must connect to various devices and systems, including infotainment systems, sensors and other critical components.
• Software and tools support: The availability of development tools and software support is also crucial in selecting a processor for automotive applications. The processor must be supported by a robust and reliable development environment that allows engineers to develop, test and debug their code efficiently.

Selecting a processor for advanced automotive applications requires careful consideration of the above-mentioned factors. The processor must provide high performance and low power consumption and be able to operate in harsh environments while ensuring reliability and safety.

Commercial devices

Every automotive application has different requirements in terms of performance, power consumption, temperature range and connectivity. As a result, the optimal automotive processor should be selected according to the application’s specific requirements.

Some of the most relevant processor families used in automotive applications are available from NXP Semiconductors, Nvidia, Renesas Electronics Corp. and Texas Instruments.

NXP i.MX28 series

Featuring an integrated power management unit, display controller (resistive touchscreen), CAN, USB and Ethernet connectivity features, NXP’s i.MX28 family of multimedia applications processors is based on the Arm9 Core and is AEC-Q100 automotive-qualified.

The i.MX28 processor meets the requirements of automotive infotainment systems, featuring display and touchscreen control systems. This processor enables many features available only in high-end systems but at a price point suitable for all vehicles.

NXP i.MX95 series

Enabling the most demanding edge applications, from Industrial 4.0 and IoT platforms to the automotive connectivity domain and electronic cockpit, the i.MX 95 applications processor family includes six Arm Cortex-A55 cores, an Arm Mali GPU, a 4K VPU, ISP, an ML-accelerated NPU and Edgelock secure enclave security in addition to the NXP SafeAssure functional-safety–compliant platform development (ASIL-B, SIL2).

With high-performance computing, Arm Mali–powered 3D graphics, an NXP NPU accelerator for ML and high-speed data processing with safety and security features, the i.MX95 family is configurable and scalable, with multiple heterogenous processing domains. This includes an application domain with up to six Arm Cortex A55 cores, a high-performance real-time domain with Arm Cortex M7 and a low-power/safety domain with Arm Cortex M33. Each domain can access interfaces, including CAN-FD, 10 GbE and PCIe Gen 3 x1, and accelerators like V2X, ISP and VPU.

NXP i.MX 8QuadMax

Designed for graphics, vision and HMI applications, the i.MX 8QuadMax is an automotive and infotainment applications processor composed of eight cores (two Arm Cortex-A72, four Arm Cortex-A53 and two Arm Cortex-M4F), dual 32-bit GPU subsystems, 4K H.265-capable VPU and dual failover-ready display controllers. Also included is a high-performance Tensilica HiFi 4 DSP, enabling echo cancellation, speech recognition and pre- and post-audio processing.

The AEC-Q100 Grade 3–qualified processor supports rapid multi-OS platform deployment (Android, Linux, FreeRTOS, QNX, Green Hills and Dornerworks XEN), targeting demanding automotive applications like infotainment, HUD, HMI and electric cockpit.

Figure 2: NXP i.MX8 applications processor block diagram (Source: NXP Semiconductors)

Nvidia Tegra

The Nvidia Tegra processors are used in several automotive applications, particularly for infotainment systems, autonomous driving and ADAS. The Tegra processors offer high-performance computing capabilities and low power consumption and are designed to handle complex algorithms and tasks in real time. Tegra processors have been used in many commercial vehicles, including premium electric vehicles. Tesla Motor, for instance, uses these processors for powering the infotainment, navigation and instrument-cluster systems on its Model S sedan.

One of the most recent automotive processors developed by the Californian company is the DRIVE Thor. As announced in September 2022, DRIVE Thor is a centralized car computer integrating cluster, infotainment, automated driving and parking capabilities in a single cost-saving system. Achieving 2,000 teraflops of performance, the new architecture includes AI capabilities that enable in-vehicle infotainment and ADAS systems to run domain isolation, allowing time-critical processes to run without interruption.

Renesas R-Car

The R-Car series of SoCs from Renesas addresses a variety of automotive applications, such as autonomous driving, ADAS, connected gateway, in-vehicle infotainment, cockpit and dashboard/cluster. All processors in the R-Car family (see Figure 3) support software reusability as well as the ISO 26262 safety standard up to ASIL-D. Moreover, along with its partners, Renesas provides a wide range of software and development tools to meet the complex and large-scale software development requirements expected by the automotive sector.

Figure 3: Renesas R-Car automotive SoCs (Source: Renesas Electronics Corp.)

TI Jacinto

Texas Instruments Inc.’s Jacinto 7 is a family of automotive processors designed for ADAS and autonomous-driving applications. The processors are built on a combination of Arm CPU and DSP cores and include specialized hardware accelerators for tasks like image processing, deep learning and sensor fusion.

The Jacinto 7 processors have several configurations to meet specific performance and power requirements. All models feature hardware accelerators for computer vision and ML and specialized hardware for automotive-safety applications like ASIL-D functional safety and secure boot.

The processors support different interfaces and standards, including PCIe, Ethernet, USB, HDMI, CSI-2 and CAN-FD. They are also designed to work with the sensors commonly used in automotive applications like cameras, radar, LiDAR and ultrasonic sensors. The processors run on the unified software platform, providing open-source device enablement for Linux, RTOS, QNX, AUTOSAR and more.

MPUs, MCUs and SoCs are all essential components in modern automotive applications. MPUs offer high performance and flexibility for complex applications, while MCUs provide low power consumption and real-time control for safety-critical systems. SoCs combine the best of both worlds, offering high performance and low power consumption for advanced applications like ADAS and autonomous driving. Choosing the right processor for an automotive application requires careful consideration of the application requirements, along with the processor’s features and capabilities.