As car OEMs eagerly put together in-vehicle infotainment and telematics systems based on predominantly consumer technologies, the unanswered, and often unasked, question is: Are these consumer chips automotive-qualified?
EE Times learned during the International CES in Las Vegas earlier this month that Qualcomm's LTE chips, now making deep inroads as the in-car modem, aren't pre-qualified for the automotive market.
When asked, Qualcomm stressed that its Gobi 3G/4G LTE modems are “packaged into automotive-grade modules.”
Responsibility for putting these non-pre-qualified LTE modem chips into a module and qualifying the module for the automotive market falls, hence, to Qualcomm's licensees. A Qualcomm spokesperson explained that once its chips go inside the auto-grade modules, the modules are “provided to Tier 1s for inclusion into today's telematics and infotainment solutions.”
Clearly, there are two approaches to this issue. On one hand, car OEMs can use a chip already pre-qualified for AEC-Q100 (a critical stress test qualification for automotive ICs). On the other, they can rely on a non-qualified auto-grade chip housed in a module that's later automotive-qualified. Not so clear is how big a difference these two separate approaches make in the real world.
However, as chip companies race for design wins in in-vehicle/telematics systems, which many view as a platform for connected car apps, a few vendors will exploit auto-grade modules vs. pre-qualified auto-grade chips as a wedge issue.
Nvidia, for example, appears to believe that for a module to be automotive grade, most components inside should be automotive grade.
The advantage of using pre-qualified auto-grade chips to build auto-grade modules is clear: increase module yield.
Certain components are very sensitive to temperature and therefore would most likely need to be auto-grade for the module to pass extended temperature tests. Automotive-grade components are subject to a significantly more rigorous qualification (AEC-Q100) and production test than non-automotive-grade components. “This extra qualification and testing results in a considerably higher quality component with a considerably lower failure rate,” according to Nvidia.
The upside of the module approach, preferred by Qualcomm, is time-to-market. The use of non-pre-qualified auto-grade chips for the module allows faster implementation. However, this approach potentially includes the cost of throwing away a lot of uncertified modules that flunk the auto-grade exam.
As automotive and CE merge…
The issue comes down, finally, to which side OEMs prefer.
Thilo Koslowski, vice president and distinguished analyst at Gartner, told EE Times, “I believe that automakers still feel more comfortable to have an automotive-grade chip.” After all, it is “designed for this purpose” as opposed to “assembled for this purpose,” he explained.
The biggest gain to be had from an automotive-grade chip is decreased complexity and testing requirements, compared to using a module, Koslowski noted.
However, the Gartner analyst suspects that automakers are likely to change their minds over time. As automobiles and consumer electronics merge, “the auto industry realizes that there are cost benefits to be had by going with a module approach.”
But will they?
Tier 1s, carmakers, and chip vendors serving the automotive industry for a long time all take “auto-grade” qualifications seriously.
Freescale Semiconductor is one of them.
Ray Cornyn, vice president of Auto MCU at Freescale, explained that there are several different “grades” requirements in the AEC standard for automotive ICs — depending on where the chip is used.
Obviously, chips to be used in the power train need to be designed from the ground up for long-term reliability (e.g., 15 years) and robustness (resistant to as high as 150 degree C temperature, without using additional cooling devices).
Placing such a mission-critical automotive chip on the higher end of the spectrum and the module approach on the opposite end, Cornyn explained, there's a middle-ground solution, which Freescale offers with its own multimedia chips.
The difference, said Cornyn, is that Freescale's multimedia chips, although originally developed for the consumer market, are doubly designed for automotive applications. The company makes sure that such consumer components are already characterized and tested as suitable for automotive use.
Next Page: Auto qualified “consumer type” parts
Freescale does not design the same chip twice — one for consumer and another for automotive. Instead, Freescale applies the knowledge accumulated through designing full auto-dedicated MCU products to its consumer chips, which it knows will be used inside cars.
Asked about additional steps Freescale takes in developing the company's auto-qualified “consumer-type” parts (vs. consumer-only parts), Cornyn explained, “We do an additional on-chip SCAN test to guarantee silicon test coverage.”
Freescale also characterized and validated a “semiconductor process” for long-term reliability and automotive environment use cases.
Further, the company's engineering team simulated timing (frequency) and layout over wider process variation windows so that it can ensure consistent yield and frequency capability. Cornyn stressed, “We do not just screen a few parts to be shipped for auto. We ensure that a consistent production volume will meet automotive temperature and quality requirements across years of production.”
The company makes sure that both ESD protection and package capability comply with automotive reliability standards. “We then qualify these parts to the AEC100 Grade 3 (or better) automotive standards.”
Cornyn's unstated warning to competitors is that learning what it takes to make auto-grade chips takes years of actual experience.
When Qualcomm announced earlier this month at CES that its new Snapdragon 602A will be an “automotive-grade” infotainment chipset, many in the automotive chip industry wondered: How much has Qualcomm really learned about auto-grade requirements? The fact is that Qualcomm's own LTE modem chip, although used by carmakers, has never been pre-qualified as auto-grade as a standalone chip.
According to Qualcomm, the plan for Snapdragon Automotive Solutions is “to pre-integrate these automotive-grade modules and automotive-grade Qualcomm VIVE WiFi/Bluetooth modules with the automotive-grade Snapdragon 602A processor to allow Tier 1s and automakers to develop and deliver next-generation connected infotainment systems.”
Then, there's the matter of degrees of so-called automotive compliancy.
Strategy Analytics associate director Roger Lanctot pointed out to EE Times that, beyond LTE modem chip itself, many of the other components involved in building cellular modules are also not automotive qualified. They include power amplifiers, memories, front-end modules, etc.
“So it is still not possible to have a fully automotive compliant module,” he told us.
This article was originally published on EBN's sister publication EE Times .