There is a myriad of different CCA designs, types, and capabilities. However, PCBAs are largely comprised of 4 basic elements.
The material supporting all the electrical components together. Substrates can vary greatly depending on the type of PCBA. For example, you can have flexible, ridged, and metal core boards.
Below is a video displaying the different electronic components that can be placed on a substrate.
A thin layer of copper is laminated to the substrate of the PCBA connecting the electrical components with conductive tracks or traces. The number of copper layers depends of the type of PCBA, and can range from single-sided, double-sided, and multi-layer boards.
Solder masks are applied as a coating to prevent corrosion, reducing the possibility of solder shorts.
A silkscreen may be printed on circuit boards to display a legend identifying the components and test points.
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