Four key points that every current automotive product design needs to pay attention to

Vehicles can do much more than they did even a decade ago. Today’s modern connected vehicles have many convenient features, from lane departure warnings to automatic braking and self-parking capabilities. In this new digital age, our cars require a lot of software to work in tandem with the existing hardware that powers many of our cars’ important features.

As automotive innovation continues, automotive chip (system-on-chip) designers must ensure their designs meet the necessary requirements to produce increasingly smarter, yet more reliable vehicles over their long lifespans.

The four key functions required in automotive motherboard design are reliability, functional safety (FASA), quality, and security. Read on to learn how automotive chip designers can address these areas.

Optimizing vehicle performance for increased reliability

Today's modern vehicles are expected to operate for more than 15 years, so the SOCS inside should deliver reliable performance over a longer period of time. There are several factors that affect the durability of automotive chips, including process and voltage variations, wear-out failures caused by aging, thermal effects, electromigration (EM), electrostatic discharge (ESD), and environmental issues such as energy changes. To ensure vehicle reliability, designers must comply with a key automotive industry standard: EC-Q100. This requires that every automotive chip be stress tested during the design phase to verify whether the automotive system can withstand the harsh conditions it may operate in.

Issues that affect system control system reliability need to be addressed with innovative solutions at the system control system level. For example, the aging of the device must be examined by taking into account stress temperature, stress voltage, life, and switching activities, which is called the "mission configuration diagram". A good static timing analysis solution thoroughly and accurately analyzes the mission profile. In addition, automated design robustness analysis and optimization techniques are essential to identify cells that are prone to process variations or voltage changes to prevent timing failures.

Designers must also consider EM at the signal and cell levels to ensure system reliability. Semiconductor process foundries will specify specific signal EM requirements that the design must meet, including average current, RMS, and peak current. Accurately modeling, extracting, and calculating the current through the wires in the design are essential components of proper electromagnetic analysis. Cell-level EM must be modeled during the library description process in order to determine the maximum frequency under various operating and load conditions.

Additionally, chip monitors can be used to reduce operating voltages for directional performance. This can result in reduced voltage and temperature stress on the device, which will ultimately increase the life of a single output circuit. As an added bonus, continuous path monitoring also optimizes system control system performance by providing valuable analysis.

Enhanced functional safety

Automotive chipmakers must follow specific guidelines to ensure that safety-critical devices are qualified to operate in the car. Two potential sources of safety risks in automotive electronics include electromagnetic effects and hardware failures or system failures such as incorrect implementation or malfunctioning silicon aging. To reduce the safety risk of failures, automotive chipmakers must follow the ISO26262 functional safety standard, which provides a series of guidelines for certifying safety-critical devices for use in vehicles. The practical application of ISO26262 takes the form of automotive safety integrity levels, a risk classification system defined by the standard that aims to reduce failures in electrical and electronic systems.

Functional safety – involving functional safety – is an integral part of the hazard reduction approach. As part of the RTL-GDS process, the different FSA stages ensure vehicle safety and deliver three benefits: confidence in safety compliance, productivity through reduced engineering effort, and increased efficiency through increased turnaround time and improved power, performance and area (PPA).

Additionally, hardware architectural metrics (e.g., Failure Mode and Effect Analysis) must be closely tracked while designing fail-safe hardware for vehicles. To address random failures, IP, subsystem, and single-level Fault Diagnostic Analysis (FMEDA) plays a preventive role with the help of Dependent Failure Analysis (DFA). Techniques such as traceability, design failure mode and effects analysis are key to address systematic failures. These metrics will help identify and address errors in the design to improve vehicle compliance with functional safety guidelines.

Solve the highest quality defects

From latent defects and process variation to process contaminants, various factors can affect the quality of chip designs and automotive SOCS. When a design passes the test phase, a strict number of acceptable defects may be present. Testing must continue throughout the life cycle of the device to ensure that there are not too many critical defects.

However, with this ongoing testing, automotive chipmakers must now face the following hurdles:

· Time: Testing procedures can be labor intensive and time consuming.

· Cost: It is becoming increasingly expensive to thoroughly test chips.

· Space: Multiple monitoring instances and design for test (DFT) take up a lot of real estate.

A comprehensive test approach is essential to address these challenges. This includes effective advanced fault modeling tools, advanced compression and defect-driven memory testing, advanced tools for efficient implementation, and chip monitoring to generate real-time analysis.

Maintaining car safety

While security is a concern across all industries, the chips on a vehicle can have life-or-death implications. New over-the-air (OTA) software updates for application upgrades are just one example of a potential area of ​​weakness in vehicles. In addition to the ISO26262 functional safety standard, automotive chipmakers must also comply with the SECURITY/SAE214-34 Road Vehicles – Cybersecurity Engineering, which provides the following architecture to safeguard vehicles from malicious attacks:

· Continuous network security monitoring

· Project-specific cybersecurity management

· Cybersecurity during the concept and post-development phases of road vehicle product development

Relevant risk assessment methods

Ongoing cybersecurity activities

Security management

During the life of the vehicle, automakers must have procedures in place to protect the vehicle from evolving cybersecurity threats. Several approaches to achieve this goal include attack-resistant design, such as property checking, simulation, and rule checking, as well as physically inconsistent functions (PUFS), anti-programming, logic locking, and watermarking. Finally, pre-silicon simulation of attacks can distinguish vulnerabilities and confirm that mitigation measures are successful.

As automotive business group designers continue to develop and advance advanced software-defined vehicle features, it is critical that the chips that enable these features meet the reliability, safety, quality and security requirements to make our roads safer and our vehicles smarter.