Top Flaws to Watch Out for During PCB Testing

You may design what you think is the perfect PCB. However, there is no way to know if that is actually the case until you have a prototype in front of you ready for testing. Here are some of the common flaws you should look out for during the testing phase of your PCB’s lifecycle.

Poor Signal Integrity

It can be extremely difficult to determine the strength of the PCB’s signal integrity until you have it on the table in front of you with a current running through it. What’s more, the only way to fix signal integrity issues is to quite literally go back to the drawing board and reconsult your design.

Determining signal integrity is extremely important as it can point to many other issues with the design. For example, it may point towards issues with crosstalk noise or wire resistance leading to signal delays. Make sure you know some of the basic layout techniques for avoiding these issues to minimise your chances of encountering poor signal integrity.

Wrong Components

You should have consulted your component library while designing your PCB to ensure that you have all the components you need come manufacture. However, when the time for manufacturing arrives, you in fact find out that all the components you need are not available and you instead substitute something else to replace the component which you had initially chosen.

This will most likely result in your PCB not functioning the way that it is supposed to. You have designed it to respond to a very specific set of conditions and if you change one of them you cannot guarantee that the effect will be the same. Be prepared to either redesign the PCB or wait until you can get the component you need.

Short Circuits

It may be one of the simplest flaws but it is also one of the most common. Short circuits are very common in PCBs with multiple voltages in their power networks. If you have a board which uses 12V in one part and 3V in another, you need to ensure that all of it is properly grounded to ensure that a short circuit cannot appear.

Short circuits can cause major issues to a board and can even permanently damage your components if they are not addressed. Make sure you know how to identify a short circuit and how to rectify them when they do occur.

The PCB design is as much an art as it is a science and the testing phase is one of the most important in the process. If you want to ensure that you keep the testing processes to a minimum, you need to know how you can best avoid some of the flaws listed above. PCB design has plenty of scope for things to go wrong if you are not careful. Take each and every new project as a chance to learn from mistakes you have made before and you will only grow as a designer.

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