Selecting the right electronic component is one of the most critical & challenging aspects of product design. In this article, I do not aim to explain how to select different components like resistor, capacitor, transistor, digital IC, microcontrollers, relay, power management IC, connector, display, protection device, etc. as there is no one answer to this challenge. The correct answer is, you should know clearly what is your requirements are.
There are so many ways to solve the same problem, it will depend on various things like, if you need a compact design, easy to manufacture design, most affordable, most power efficient, least number of components, most reliable, etc.. So, at the end it’s a trade-off, where, you are trying to decide which component matches most of your requirements. Every component is different and needs specific attention, but, general rules of the game remains the same.
To start with, I recommend making a list of components and their critical parameters which needs to be checked. There is a number of parameters which I always consider while choosing the right component. Hope this will help you next time when you are working on a project where you need new components to be selected.
Using components from a previous proven design
The easiest bet would be to use the part you have already used in your previous proven design, this helps reduce the risk of design issues, delays, also no additional part in inventory to manage.
But, this approach has one drawback. If you stick on to an older proven component, you may miss the advantage of a new part, which may bring in benefits like more compact, more integration, more power efficient, better protection, better longevity. When starting a new design, it also brings an opportunity to try newer parts available (maybe you can have a fallback option on board if you have doubts about the new part’s performance).
New Parts Selection
Now, let us assume we have to select a part which we did not use before, so how should we approach this challenge. As mentioned before I would list all the parameters which need to be considered and then go refining/filtering from the available part database. Best would be to look for parts available with online distributors
Let me discuss some of the parameters one by one, this is based on my personal experience working with many companies on various projects:
Select manufacturer wisely. Always consider a manufacturer who has good product documentation like an informative datasheet, application notes, reference designs, evaluation board support, support channel. For complex devices, you may want to get in touch the manufacturer over email to test their support. If local Field Application Engineer support is available in your country, would be really helpful. Trusting manufacturers who do not have good product documentation and support is tricky.
Application notes from the manufacturer help a lot in understanding the application circuit and many times tested components make/rating is also provided, which reduces the risk greatly. Evaluation board can also be used for pre-qualification.
Reference Designs, Software Tools
Some manufacturers also provide a lot of other resources like industry-specific reference design, software tools to help designer evaluate the performance of the component as per your own configurations before even designing anything. This heavily reduces the development time and chances of failure.
Technical Support / Design Review Support
Component manufacturer’s support is critical. In case you are stuck, you can ask their engineer’s help. Many manufacturers also provide design review facility which greatly helps when you are designing for the 1st time a circuit with their parts. You can send them your schematics with their part used and they can help you review and tell you if everything is OK or if they have any recommendations.
Many companies maintain a list of the preferred list of manufactures and electronic components distributor this way you can take a better decision.