PCB Technology about PowerLink
PowerLink is simply defined as the use of two or more copper weights on the same layer of the circuit board. This is also known as "selective plating", the process of which is only available on outer layers.
PowerLink is an option when the specified area of the printed circuit board needs to carry current value more than the standard 1 oz or 2 oz traces can handle within a reasonable trace width. Other options for solving this problem are to connect the vias in parallel at the other layers, solder a wire jumper jumper to the affected area, or, in extreme cases, apply bus bar pieces to the board by soldering or using a threaded fastener.
Standard or light copper circuits are usually between 1/2 oz and 6 oz copper. The designated area as heavier copper can be larger than the base copper foil.
At EPCB, we normally see heavier copper ranges from 4 oz up to 40oz and in some special applications we have built boards with designated areas of 100 oz copper. The heavier copper designated areas are created by plating up from the base copper.
PowerLink has several steps. For example, the picture directly shows the difference among 10 oz, 20 oz and 30 oz copper areas. While 100 oz copper or more is possible, the practical restriction is more dependent on the economics. A relatively small difference from light to heavy copper (4 oz to 10 oz) can be made at a reasonable cost. As the amount of required plating increases, the cost increases as well. In this case, we will recommend other options that can be more economical.