The entire automotive ecosystem is being reshaped by vehicle electrification, assisted and autonomous driving, and the connectivity needed to make it all work. So far, it’s not clear just how smoothly this will all come together.
In this redefined world, electronics and software will provide differentiation rather than mechanical engineering and possibly even brand name, creating change on a scale the automotive industry has never witnessed before—particularly in such a compressed time frame. The infrastructure, processes and methodologies in the automotive world that have been carefully constructed and refined over the course of more than a century are now undergoing massive disruption in the race toward autonomous vehicles.
These changes have big implications for the chip world, as well. Automotive has emerged as one of the big new opportunities for semiconductors. This market is well funded and highly motivated to adopt advanced electronics, but it’s also a very different world. Chips developed in cars need to work well for long periods of time under harsh conditions, and they need to adhere to a set of evolving standards and regulations unlike anything the majority of chip companies have ever dealt with.
“On the design side, you want to make sure you design with the latest design rules and implement those design rules,” said Ron DiGiuseppe, senior strategic marketing manager, solutions group at Synopsys. “You must have a good tool suite that can not just implement it, but do the verification. Part of that verification is how the product — either at the chip level or even at the IP level — reacts to possible failures. As such, you need to have a design flow where there are tools that can inject possible failures, then simulate to see how the product reacts to those failures in terms of safety critical. If you’re going to do ADAS or autonomous driving, those systems and the chips and the IP blocks that make up those chips have to be compliant with ISO 26262.”
This represents a big shift for chipmakers. In markets such as mobile phones or computers, if any part of a system failed, it typically was patched with software and replaced in the next rev of a product, which usually was sometime in the next few years. But with safety critical markets, such as automotive, industrial or medical, these parts need to function reliably for 10 to 15 years.
“Reliability and safety are the keys,” said Neil Stroud, director of technology strategy, embedded and automotive line of business at Arm. “EDA tools used to develop safety-related IP or software must undergo a tool qualification analysis that proves they are fit-for-use and do not introduce faults that could potentially violate safety goals.”
But this is something of a fast-moving target. Assisted and autonomous driving standards for the automotive ecosystem are evolving alongside the technology for electrification of vehicles. Consider the upcoming second version of the ISO 26262 standard, automotive designs and IP, for example, which will require constant runtime monitoring to achieve necessary safety levels, according to Steve Pateras, product marketing director at Mentor, a Siemens Business. “This will require the integration of monitor functions into the design. Examples of this include voltage monitors, ECC logic for memories, and logic BiST for random logic. Design flows will need to include tools that enable the integration and verification of these capabilities.”
Pateras noted that the ISO 26262 standard also specifies a number of hardware functional safety metrics and associated levels for the different device ASIL classifications. “These metrics include the single-point fault metric (SPFM), which is the probability that a single defect will not result in an unsafe state, and the probabilistic metric for random hardware failures (PMHF), which essentially represents the overall probability of failure per hour. The analysis necessary to calculate these metrics is quite complex, making the automated calculation of these metrics a critical requirement for large complex IP blocks and designs.”
That’s just one piece of the puzzle.
Commodity chips are no longer just commodities in the automotive world, because even an insignificant sensor that malfunctions—or which doesn’t function well enough—can cause an accident.
“A big challenge with autonomous vehicles is the accuracy of the sensors,” said Stephen Breit, vice president of engineering at Coventor. “There are a number of sources of error. One is manufacturing. Thermal sensitivity is an issue, as well. So you need to design these to be more precise, more linear and less temperature-sensitive. The precision requirements for autonomous vehicles are much higher than for an airbag or rollover, where you could just exceed the threshold and apply current.”