In any manufacturing process, testing is absolutely fundamental to the operation. If you do not have a good test process in place you could end up manufacturing lots of boards that contain defects and that will cause your products to fail once they are in the hands of the buyer. As you can see, this is why testing is so crucial, as otherwise you can seriously start to wreak havoc with your reputation and your customer relationships.
However, testing is not simply an add-on, and you need to ensure that during the design process you are carrying out specific test procedures at different stages throughout the process. Of course, it makes more sense to find a fault in a product before it has been sent away to be manufactured and then having to scrap them. Here, we are taking you through PCB design and what the best practice steps are that you should be following.
What Is In-Circuit Testing?
When manufacturing, you will need to carry out the MDA test which is the manufacturing defects analysis and this is carried out by specialist automated test equipment. During this analysis, it will check the components across the PCB and verifies different aspects of it such as the diodes and transistor orientation, passive component measurements and basic supply voltage measurements. It can also look for things such as an open circuit that has not been soldered together properly or short circuits.
Why Is PCB Design So Important?
If you want to carry out this detailed analysis then you will need to have the right type of programmes in place. This is a non-recurring engineering charge but you will need to purchase new equipment each time you have your PCB design changed. This is why you need to design PCB with this testing in mind.
How to Design PCB
With this in mind, we would recommend that you have all of your components on one side and the test pads on the other. When doing this testing there will be certain requirements such as a minimum 0.05 inch test pad per net which is designed into the PCB and is a target for the fixed test probe or pads that need to be at least 0.1” apart from both each other and other components. The Altium PCB autorouter is recommended to be used here as this can stop you from making silly mistakes as it will let you route signal nets really quickly, but will also ensure that your device obeys the critical design rules, and this will make it easier to work with lots of different features and you are less likely to find mistakes when it comes to testing.
As you can see, PCB design really is the key to success when it comes to successful testing of your manufactured product. Without this PCB design, many more design flaws would only be captured at the end and it can save you lots of time and money during the process.