label: pcb board,Printed circuit board
Visual and electrical inspections are made throughout the manufacturing process to detect flaws. Some of these flaws are generated by the automated machines. For example, components are sometimes misplaced on the pcb board or shifted before final soldering. Other flaws are caused by the application of too much solder paste, which can cause excess solder to flow, or bridge, across two adjacent printed circuit paths.
Heating the solder too quickly in the final reflow process can cause a "tombstone" effect where one end of a component lifts up off the pcb board and doesn't make contact. Completed pcb boards are also tested for functional performance to ensure their output is within the desired limits. Some boards are subjected to environmental tests to determine their performance under extremes of heat, humidity, vibration, and impact.
