ADVANCED AND NON-STANDARD PCB MANUFACTURING CAPABILITIES
There was a time when the PCB manufacturing industry included a fair number of bucket shops, so called because much of their processing was done in small portable tubs filled with etchants, solvents, and other mysterious solutions. They cranked out very basic, low-cost, low-complexity PCBs, using equipment and methods that were questionable at best. Their business and environmental practices were often similarly questionable.To get more news about
Cavity PCB, you can visit pcbmake official website.
The good news for circuit board customers is that bucket shops are a thing of the past. Those fabricators who remain viable can execute all basic production steps repeatedly, with a low likelihood of scrap, on printed circuit boards that would have been considered insanely complex just a few years ago. Still, there are higher-end processes that not every supplier is equipped to do.
It is important to be sure that the circuit board you are about to order is going to a PCB manufacturer that can handle several difficult design features simultaneously. Otherwise your order could be scrapped, or it could show up on your dock with undetected manufacturing errors that will complicate assembly, installation, or function. The following post explains what some of the more difficult processes are, so that you can be sure to identify an appropriate fabricator for your order.
Controlled Impedance
There was a time when many small to medium shops were not able to support impedance testing, but those days have passed. Controlled impedance PCB designs are now so common that the ability to check impedance results has become a basic requirement for remaining in business. It is now possible to have your order tested no matter where it is built. If you supply the necessary information at the beginning of your project, your boards should arrive with a report of the results. Expect to pay a small up charge per PCB. The up charge covers the cost of setting up and performing the test, which is not done on the same machine as the one used for checking basic continuity. It also covers the potential small increase in fallout for boards which fail impedance testing, despite being free of other manufacturing errors.
Wraparound Edge Plating
Occasionally, it is desirable to form a connection by wrapping the plating around the PCB edge, rather than by means of a standard via hole, so that the edge can serve as a conductor. The fabricator accomplishes the wrap plate by performing an extra primary routing operation immediately after drilling. The purpose of this routing step is to expose the PCB sidewall so that it can be coated with electroless base copper (or an equivalent) in the same manner and at the same time as it is applied to the drilled holes.
After the photographic circuit image has been applied and developed, the electroless layer provides a conductive surface onto which the thicker, more durable electrolytic copper can adhere. If the artwork includes a pad or other shape that defines the routed area as a plated feature, the electrolytic copper plating will coat the routed channel to form the desired connection. While this process adds steps, plus a small amount of complication in the planning of array setups and machining processes, it is not overly difficult to arrive at a good result.
