Mike Garner

Managing Director at Garner Osborne Circuits Ltd

5 reasons printed circuit boards fail – and how to avoid them

PCB failure is frustrating. It’s costly, inconvenient and can negatively affect your brand. Printed circuit boards are sensitive things though, and failures can be caused by a number of things – from the weather to age. Here are the top five reasons that printed circuit boards fail, and how you can reduce the risk of failure.

1.    Environmental factors

PCBs in damp or particularly hostile environments are prone to these types of failure because, as temperatures change, the PCB can expand and contract and boards may become warped. With all this movement it’s easy for soldered joints to become damaged, leading to board failure. This sort of issue is most likely to be seen when a component’s barrier has been broken and atmospheric particles such as dirt, dust and moisture get into the component, or circuit board.

2.    Poorly manufactured components.

One of the most common reasons for failure is a poorly manufactured PCB. Issues such as incorrect soldering temperatures, misalignment of the bare board & components and dry joints all indicatives of a poorly manufactured PCB.

When looking for a PCB manufacturer, find one that has been around a while, with a good reputation. The business world has a beautiful way of casting off the poor manufacturers over time.

3.    Burnt components

Printed circuit boards can get pretty warm, and in doing so components work outside their standard operating temperatures. The amount of heat that a component can take is finite and depends largely on its size and structure. Make sure that when designing your PCB your components have sufficient space around them to allow air to circulate around any heat sinks, and they will be working within their operational capability.

4. Atmospheric conditions on manufacturing

The conditions of the room in which PCBs are assembled can also impact a PCB’s performance. If PCBs get dusty and dirty, or come into contact with hair or bugs, these can all cause faults. Ensure that the labs in which PCBs are assembled are kept clean and dry for quality circuit board printing and assembly.

5. Acid traps and other design flaws

Sometimes the reason for a failure actually lies within the initial design. Where acute angles are used in a circuit, acid can get caught up during the etching process. Etchant in an area for longer than intended can begin to eat away at the circuit making it defective. It’s best to avoid 90 degree angles in circuit board design where possible. You can read more design tips to enhance the quality and reduce the cost of your PCBs in ‘Adding our expertise to save you money’.