Printed Circuit Boards
In our series on Electronics Design we have looked at the Electronics Design Process from Requirements Capture, Technology Selection, Component Selection, Schematic Capture and finally PCB Design of the Printed Circuit Board including PCB Layout. Now we have a design and the Electronics CAD files to make a Prototype.
There are a number of steps involved in making a PCB and the following infographic provides an overview.
This infographic is courtesy of Newbury Electronics.
PCB Manufacturing Problems
That is a lot of steps. And there are things that can go wrong. The main pitfalls to avoid in the PCB Design Process are:
- track widths too narrow
- clearances between tracks are too small
- acute angle entry to pads
- component footprints have pins in the wrong place or the wrong size
- component outlines are wrong
- silkscreen or overlay over solder pads
- via annulus too thin
- mounting holes in the wrong place or the wrong size
- PCB outline incorrect
- PCB 3D profile doesn’t fit into the intended enclosure
And there are a range of issues that can affect the PCB Manufacturing Process. These include:
- misalignment of drill holes to tracks to PCB outline routing
- internal cut outs missed / not routed
- over etching or under etching of the copper
- incomplete plated through holes
- poor surface finish
- poor FR4 and copper bonding or moisture ingress leading to delamination
Maybe you are wondering how a PCB ever gets made successfully? This comes back to undertaking the PCB Design with an understanding of both electronics engineering design principles and the process capability of the manufacturer into account. And when you get it right, the final product can be pretty awesome. A good example can be found at this post about making a Fine Pitch PCB.
Next we will look at the PCB Assembly process.
Successful Endeavours specialise in Electronics Design and Embedded Software Development. Ray Keefe has developed market leading electronics products in Australia for nearly 30 years. This post is Copyright © 2015 Successful Endeavours Pty Ltd.