Clearly, many of today’s innovations in automobile design result from the growing demand for more electronics within the car. Cars now come with state-of-the-art audio and video systems, high-tech and graphic-rich navigation systems, and wireless technologies for many types of communications.

Safety electronics should make a quantum leap forward with advanced driver assistance systems (ADASs), which are involved with braking, steering, and collision avoidance. When drivers become distracted, the risk of an accident quickly increases. In 2008 alone, according to the National Highway Traffic Safety Administration (NHTSA), 6000 Americans died due to a distracted driver and another 500,000 were injured. 

Automakers are now turning their attention to accident prevention, with a focus on improving the driver’s experience. To lessen distractions, key vehicle and driving information needs to be displayed in front of the driver, specifically in the dashboard. 

The instrument cluster, a space once reserved for electromechanical gauges and light indictors, is transforming into a new digital information center for drivers. Thanks to the advancement and maturing reliability of digital thin-film-transistor (TFT) displays, improved signal processing power, and high-speed digital communication, analog-based systems are rapidly migrating to digital system displays.

Today’s dashboards built around TFT displays still provide basic vehicle information, such as drive train position, speed, fuel levels, and engine status, while bringing in additional data from outside the car. This added information comes from new innovations like 360° cameras, night vision, lane-departure warning, blind-spot detection, and 3D graphic navigation data.

Digital clusters enable a more cost-effective and flexible means to converge all vehicle and safety information, which further minimizes any unnecessary distractions. The driver no longer needs to look down or fumble with the center console searching for music, make phone calls, look up driving directions, or turn one’s head to look at a blind spot.

While these new advances offer many new and exciting options, they also require designers to find innovative solutions to control costs as well as deliver critical performance capabilities and ensure long-term product reliability. This article will present some automotive design/reliability constraints, a review of digital cluster architectures, and reasons why memory subsystem tradeoffs may impact your next project’s performance, reliability, and cost. 

Digital-Cluster Design Challenges

Digital clusters must support high-performance, real-time processing requirements (e.g., existing consumer-based display platforms) while exponentially increasing the design’s long-term reliability. Automotive-market OEMs (original equipment manufacturers), tier-one suppliers, and customers will not accept display malfunctions as a simple inconvenience, much like those typically associated with consumer-based phones or PCs.

The new digital cluster is creating a user-friendly, non-distractive, and informative environment to promote safer driving. It must deliver these high-performance levels and provide long-term operational reliability while operating in very demanding and harsh operating conditions (such as extreme temperatures of -40°C to +105°C). These stringent automotive environmental, safety, and quality requirements drive long development cycles—sometimes extending to three or more years—before the display technology debuts in a car. 

Automotive designs follow very methodical planning, design, and verification practices to identify and mitigate operational or reliability issues. As part of this process, an automotive designer often selects electronics suppliers that develop their products using high-quality design methodology, such as TS16949, and qualify them to meet the Automotive Electronics Council’s (AEC) stringent AEC-Q100 standards.

Continue on next page