The Definitive Guide to an Electronic Assembly Design Review / 7
Before subjecting an assembly to tests and evaluation, you should know how individual components
perform under stress. Are all components of a board compatible? Are there any components you can
eliminate f rom consideration f rom the start? Similar to establishing reliability goals, a component stress
review represents a small step that helps your design review operate smoothly and quickly.
This step involves examining data sheets for every component that comprises your assembly. This enables
you to:
Determine your components' operating temperature range to identify the part(s) that have the least
amount of margin with respect to the operating conditions.
Identify a replacement part with better margins.
Analyze the materials used in your components' manufacturing, as different materials have different
compatibilities within the circuit board.
Examine critical components — including optoelectronics, custom parts, memory devices,
electro-mechanical components and ceramic MLCC capacitors — to ensure product life expectancy
will be met.
Evaluate new technology devices (e.g., small device features) to determine if the new, finer geometries
will function for the intended duration of operation. All components in the BOM are examined for
derating criteria, moisture sensitivity level (MSL) and temperature sensitivity level (TSL). This analysis
often identifies parts where extreme care must be undertaken in manufacturing to ensure no moisture
penetration occurs.
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BOM (Component) Stress Review
