Timing devices have been critical components in telecom, wireless infrastructure, and high-speed communications applications for decades. Clock generators, buffers, and oscillators are the unsung heroes for countless networking and communications systems. In fact, the internet would come to a standstill without timing components. Modern cars have become high-speed networks on wheels themselves, and they too would cease to run without timing chips.
Timing is gaining much more demand within the automotive market due to two megatrends steering the future of semiconductors in the automotive industry. The first, electrification, is being driven by the adoption of hybrid and electric vehicles (EVs). The adoption of EVs is expected to surge over the next decade as the industry continues to lower battery costs, improve charging capabilities, and extend EV driving range.
Cars are also becoming smarter, laden with sensors and intelligent systems, enabling the second trend: autonomous driving. In the last few years, collision-avoidance detection and braking, automatic parking, lane-change sensors, as well as other driving-assistance technologies have become common features in high-end cars. As these features gradually migrate to mid-range cars, the next frontier will be new advanced driver-assistance systems (ADAS), autonomous driving, and smart telematics that further improve driver awareness and safety, as well as the overall driver experience.
Advances in semiconductor technology are powering the innovation behind vehicle electrification and autonomous driving. According to market research firm IHS Markit, the semiconductor content per car will double from $312 in 2013 to $652 in 2025, growing approximately 8% per year. Electronics for hybrid/electric vehicles and ADAS are the fastest growing automotive market segments, at 29% and 13% CAGR, respectively.
Drawbacks of Scaling Quartz
While the pace of innovation in the automotive market has accelerated in recent years, one area that’s lagged behind is the timing technology used to provide reference clocking in ADAS, autonomous vehicles, and infotainment applications. Historically, automotive system developers have relied on quartz crystals and crystal oscillators to provide reference timing in these applications. As the reference timing complexity of these systems increases, the easiest solution is to simply add more quartz-based components to each new design.
This approach has multiple drawbacks and limitations. In addition to the cost and complexity of adding more components to a design, quartz is inherently sensitive to shock and vibrational effects that can impact the long-term reliability of the system.
Automotive applications also typically require extended temperature operation, often −40 to +105°C. Operation at high temperature for long periods of time can negatively impact long-term aging and the product lifecycle for quartz-based components. Collectively, these limitations with quartz make it difficult for automotive hardware developers to design scalable solutions that can grow with overall system complexity.
In the past, it has been prohibitively difficult to replace multiple discrete frequency references. Traditional clock integrated-circuit (IC) solutions were unable to generate multiple unique frequencies from a single device due to frequency synthesis restrictions or degraded clock-jitter performance when generating non-integer-related frequencies. In addition, replacing multiple discrete quartz references with a single clock IC increases printed-circuit-board (PCB) signal-routing complexity and requires distribution of clock signals over long traces.
New Timing Advances for Automotive
New reference clocking solutions are now available to address these system-level challenges. These solutions have significantly lower jitter with greater frequency flexibility, enabling multiple non-integer-related frequencies to be generated by a single IC. They also support integrated signal-integrity tuning capabilities to simplify PCB clock routing and distribution.
Similar timing solutions have been used in networking, communications, wireless infrastructure, and industrial applications for many years. To take advantage of these advances in timing technology, automotive hardware designers should consider jitter performance, frequency flexibility, and signal integrity when selecting highly integrated reference clocking solutions for new designs.
The pace of technology innovation in automotive applications continues to accelerate and shows no sign of slowing down, with EVs and ADAS driving the next wave of electrification in the automotive market. Silicon-based timing solutions have improved performance and system-level reliability in networking and communication markets for many years. Now, the automotive market is poised to benefit from similar timing technology, easing the industry’s adoption of unified clocking solutions that improve system reliability and reduce cost and complexity in automotive applications.
James Wilson serves as the general manager of Silicon Labs’ timing products, managing the company’s overall timing business and directing product strategy, roadmap development, new product initiatives, product management, software development, and marketing initiatives. As part of his role, Wilson has been a key contributor in architecting Silicon Labs’ online strategy to offer mass-customized clocks and oscillators using simple web-based tools. Prior to joining Silicon Labs in 2002, Wilson held a variety of marketing, product management, and engineering roles at Freescale Semiconductor (now NXP) and various startups. He holds a BS in mechanical engineering and a Master’s in business administration from the University of Texas at Austin.