Storing and processing massive amounts of data quickly is a requirement with today’s vehicles. Automotive manufacturers face constant pressure to combine processing power and keep digital systems streamlined and cost competitive. Now there’s a new, somewhat-surprising development. Those in-vehicle infotainment (IVI) systems with their engaging, high-resolution screens and functions that increasingly emulate smartphones? They’re not just for fun anymore. Designers are integrating IVI with the instrument clusters for more-critical systems that require functional safety (FuSa) compliance.
The emergence of digital instrument clusters introduces new graphics requirements. To meet these requirements, IVI system architecture has been integrated with the instrument cluster into a common architecture known as a domain controller. There are multiple motivations for this consolidation including cost reductions and delivery of a simplified architecture that accelerates opportunity for innovation.
The processing platform in the IVI system already has a graphics capability, thus using this as a common domain controller helps eliminate system redundancy and provides overall system cost reductions. Having the graphics interchangeable between the IVI and cluster user interfaces offers an enhanced experience to the user. At a system level this consolidation also reduces interface complexity.
Despite the benefits, consolidation has its challenges
As beneficial as this consolidation is, potential FuSa considerations may arise. Certain information in the cluster is used to alert the driver to vehicle functions, and a portion of that information can have an impact on vehicle and passenger safety, so strict compliance requirements may apply.
For this reason, the domain controller architecture is divided into two domains. The first domain is for the safety-critical interface to the instrument cluster, which typically gets certified under the Automotive Safety Integrity Level B (ASIL-B). Then, a second domain controls other connectivity in the vehicle, separately enabled by a telematics control unit (TCU) and often isolated by a secure gateway.
The integrity of the safety-critical information is vital. The level of ISO 26262-compliance required will first be established at the system level based on hazard analysis, which considers failure severity, controllability and exposure. Integrators have various options under ISO 26262 requirements for integrating semiconductor components into their systems, such as: using components with the same ASIL as the system, performing ASIL decomposition and performing a hardware evaluation of the component, etc.
1. Airbag (ASIL-D)
2. Instrument cluster (ASIL-B)
3. Engine management (ASIL-C to D)
4. Headlights (ASIL-B)
5. Radar cruise control (ASIL-C)
6. Electric power steering (ASIL-D)
7. Vision ADAS (ASIL-B)
8. Active suspension (ASIL-B to C)
9. Antilock braking (ASIL-D)
10. Brake lights (ASIL-B)
11. Rear view camera (ASIL-B)
Some key vehicle components are covered by ASIL certifications
To achieve ASIL certification, the infrastructure supporting the critical information was historically isolated from other vehicle functions and modeled as deterministic with high availability. In earlier IVI systems, allocating functional safety requirements to the different components led integrators to accept “quality management” (QM) memory devices. However, with the integration of additional interfaces — such as driver monitoring, eMirrors, etc. — into the domain controller there has become an increased interaction between IVI and other critical vehicle functions. System integrators will be increasingly challenged to meet the system FuSa requirements as modeled by simply integrating QM memory components.
To meet this challenge, the memory products themselves may need to be developed to rigorous standards, in compliance with ISO 26262. Previously, DRAM- and NAND-based storage products have been limited to QM-grade, either due to an absence of demand by customers and integrators or a lack of development compliance support by memory suppliers. Recognizing this evolution, Micron has introduced a series of functional-safety-evaluated memory components.
Micron announces industry leading solutions for automotive safety
Given our extensive understanding of the automotive market and the role and importance of memory in safety applications, Micron is pleased to announce the industry-leading portfolio of automotive functional safety memory solutions: the perfect solution for next-generation IVI applications. Further underscoring Micron’s 30-year commitment to delivering leadership solutions to the automotive market, the FuSa solutions reflect an extensive series of investments across many facets of the company.
Micron’s new automotive-grade LPDDR5 memory is the first product within our broader automotive-compliant product portfolio to be deemed suitable for safety systems at any ASIL level – making it optimal for next-generation domain-based IVI applications. Micron’s LPDDR5 product is accompanied by a hardware evaluation planning and analysis report, assessed by the independent third-party, industry-recognized consulting company exida. Consultant exida has concluded that the product is suitable for systems up to and including the most stringent level, ASIL-D.
FuSa documentation collateral for this memory product includes not only a safety analysis report and a safety application note, which are a more typical supplier-provided deliverable, but also this hardware evaluation report developed within Micron. The content of this evaluation provides customers with additional information to help them demonstrate their own system compliance to ISO 26262-5. This product and the accompanying hardware evaluation report represent the next milestone in our journey towards a broader LPDDR5 portfolio that has increasing levels of FuSa system integration support.
Moreover, this product is also an additional first of its kind in innovative functional safety development: it is the first and only DRAM to contain a unique “safety engine” which can meet ASIL-C targets for random hardware errors with stand-alone component functionality and meet ASIL-D levels with additional support from the host system. Micron’s JEDEC-compliant safety solutions will allow system integrators to better ensure that the DRAM minimizes systematic failures while providing significant enhancements in failure detection capability as well as also improving system performance, power, cost and availability, compared to standard JEDEC LPDDR5 solutions.
Keep in mind that, while Micron delivers an unmatched memory and safety product line-up for the intelligent edge for the fast-changing automotive environment, Micron’s customers and system integrators are ultimately responsible for justifying that all electronic components are suitable for safety-related systems. It’s critical that they ensure via system design that the failure of any component does not result in a human or vehicle safety impact.
Micron as the memory developer is in a position of product expertise and design data availability to support customers for system-level analysis and integration of memory components. By delivering the first LPDDR5 memory that can meet ASIL-D standards, Micron’s safety-optimized products help automotive designers meet FuSa requirements for integrated IVI systems.
Read the white paper: “The Role of Centralized Storage in the Emerging Interactive Cockpit.” To learn more about Micron’s safety solutions for the automotive industry, go to micron.com/fusa.