The PCB development process, like any other product, includes several steps, starting from concept, then product design, implementation, virtual prototyping (if convenient), physical prototyping and optimization.
The physical PCB prototypes are initially completed in the prototype design, but real PCB samples must be produced before mass production. It is recommended to fabricate PCB samples in the same factory that will be in charge of the mass production. Making PCB samples are rather costly, therefore before ordering samples, a full functional prototyping board variant must be tested successfully.
Files (usually saved in Gerber format) generated by the PCB development software are sent to the manufacturer. After PCB samples are done, they have to take a number of tests, covering visual inspection, computer inspection, and X-ray examination.
The automation system checks for possible solder joints, missing solder, and mismatch in size between components which are to be assembled and holes where components are to be placed. Sometimes manufacturer may evaluate for errors in the PCB design, these errors are fully under designer’s responsibility.
PCB samples should meet all the general criteria for PCB design and have long-term sustainability under environmental conditions where it will be used.
Another fact that can not be ignored is that successfully tested PCB samples do not guarantee functionality after components are placed. The way components are soldered to the board plays a critical role in the function and performance of PCB board. The fully assembled PCB is called PCB assembly.