Plated through holes (PTH) and vias are structures that interconnect signal circuits at different PCB layers. They are typically categorized as through vias (or PTH), blind vias, and buried vias. Due to the higher I/O density and smaller electronic packages evolving in the past decades, the demand for high density interconnects has increased significantly.
Electric vehicles are practically computers on wheels. New innovations such as active and passive safety systems, electric propulsion, and semi and fully autonomous vehicles have all contributed to an increase in the usage of electronics in automotive applications. More importantly, automotive designers must still adhere to the same size and packaging constraints to ensure vehicles’ size and weight does not increase. To resolve this dilemma, automotive designers often rely on components being tightly placed on both sides of the Printed Circuit Board (PCB) to ensure the most efficient use of board space.
Dr. Natalie Hernandez has been a Product Engineer at DfR Solutions since November 2016. Before, she completed her PhD in Physics at Lehigh University and served as a graduate research assistant working on spectroscopic studies of rare-earth doped wide bandgap semiconductor materials, and has since made the jump to electronics reliability engineering. After 7 months in her new role, here are some of the key takeaways she’s learned about the industry.
When compared to the electronic systems in industries like commercial and industrial equipment, today’s avionics systems face several unique challenges. In addition to operating in rugged environments for long periods of time, they must also satisfy rigorous safety and reliability standards. Most importantly, unlike other industries, they must meet these standards while using commercial-off-the-shelf (COTS) semiconductor devices (logic, memory, etc.) and electronic assemblies that have been designed and qualified for other applications with less rigorous requirements.
The constant demand for smaller, faster, more reliable electronic components continues to drive innovation in component packaging. Component engineers are relentless in their quest for new and better ways to improve BGAs and packaging silicon. Recent advancements include going coreless and multi-chip modules, but silicon technology advances dictate continued improvement in packaging.
Product lifecycle simulation is an effective tool for determining how long electronics in automotive and other applications will perform before failing. However, there are four distinct categories of electronics with disparate levels of lifetime expectations:
Failure is a possibility with any component on any PCB. In many cases wearout is the culprit, leaving engineers to deal with the aftermath of dissecting what went wrong and possibly re-engineering the component to avoid recurrence.
Nearly one-fifth of electronics designs that are tested fail. That means nearly one-fifth of electronics designs are reworked or scrapped in favor of a new design. The resulting production delays and cost overruns mount, further threatening profitability in an automotive industry that’s already grappling with the margin-shrinking impact of increasing price-based competition.
Automotive electronics are routinely exposed to harsh environments that introduce internal and external factors that could cause failure. Of particular concern is thermal cycling since automobiles are ideally designed to last more than a decade, during which time regular and frequently major temperature fluctuations occur. Long-term product life combined with prolonged thermal cycling present unique failure risks.
Just because an automotive power module has a projected 20-year life expectancy doesn’t guarantee long-term reliability. In fact, these modules are routinely exposed to vibration, shock, humidity, salt spray and other factors that can quickly degrade power and ultimately cause failure.
