THE NCAB Group boasts a standard printed circuit board (PCB) specification which is above and beyond the Institute of Printed Circuits (IPC) requirements and specifically across 14 key points in the manufacturing process. Reliability is built into the process from the start.

Have you ever designed a board, but then received feedback that it couldn’t be manufactured unless changes were made? Or maybe you’ve designed a complex board and sent it to the factory, only to find out that the manufacturer didn’t build the board to your expectations?

PCBs are becoming more complex. The factory options are growing and the expectations around product lifecycles are becoming longer.

For fire industry products, two key points of the NCAB Group’s specification stand out as being ideal. First, there’s a minimum requirement of 25 um copper thickness in the barrel of the plated holes, which is IPC Class 3 requirement. This thicker copper in the holes has been proven to be beneficial during the shock tests of the products as there’s less chance of the copper cracking under stress and then less chance of a field failure.

Second, there’s a stated thickness requirement of the solder mask, thereby ensuring a better coverage and less low spots/weak areas. This has been proven to aid the SO2 corrosion testing procedures to which these products are subjected as the thicker soldermask helps to protect the copper during tests.

As a designer, you now have to think about more than just the software used to produce designs. In order to ensure a robust design, there’s a need to understand how to design for manufacturability, how to design for the environment, how to design for reliability and design for test, etc.

Considering all of this means that the NCAB Group has to be aware of the expectations and, in some cases, the correct terminology necessary in order to make this happen.

Guided by the IPC

In order to help the designer, the manufacturer and the end user customer work towards the same goal, the IPC created standards to underpin the assembly and production requirements of electronic equipment and assemblies.

Through the use of IPC standards, board designers are able to design robust PCBs that achieve the necessary results and minimise their time to market. Designers can have confidence in a reliable board when the end product is used in the field.

Is the use of standards really that important? Absolutely. Consider producing PCBs without defined standards. The end result would not always be a product that meets expectations. There would be a risk of various interpretations of the same aspect. The correct quality levels could not be assured. There would be no way of comparing ‘like for like’ products or factories.

Further, a guaranteed time to market would be based upon chance rather than good factory selection and good design.

Based on an agreed stance that we need standards, are the IPC standards themselves effective? Yes. Through implementation of IPC standards, the designer, manufacturer and end customer derive many benefits.