You may watch some of the Great Search videos by Ladyada from Adafruit for inspiration: https://www.youtube.com/watch?v=_1kLyEeAwtc She focuses on looking for parts on Digikey but the ideas are the same regardless of which supplier you are using.

It´s a creative process, just like choosing materials for designing furniture :P

One moment a component is the exact right one, the next a newer and better component is out there.  

https://hackaday.io/project/176209-the-gem-500w-lightheatsource

My advice; Have faith in your imagination and creative faculty (brain). Take the time to move back and reflect. The design will evolve. 

I personally enter in the relevant electrical parameters and of course stock and availability. I often narrow down the package options as well, even if I don't know exactly what I need. 

Then I sort by price, and scroll until I see something I like. Don't necessarily go for the cheapest option, but just start there and work your way up.

Consider the importance of good documentation and application notes.

Many people cobble something together by copying portions of eval boards or reference designs.  Usually that works out perfectly fine.  The parts selection is mostly already done by whoever published the original designs.

As you do this, you'll build up a repertoire of circuits & techniques you've personally experienced working.  Usually leftover parts come along with that experience.  Especially the 2nd time you buy those particular parts, you'll probably buy a good amount extra because you've personally know the circuit works and it's likely to be useful for future projects.

Most electronic parts can be considered either single-source or "commodity", meaning compatible & interchangeable versions of the part are available from multiple manufacturers.  The commodity parts are rarely advertised or promoted much, but as you see more designs, they're very commonly used.  For example, 2N3904 (and a lot of other "3904" parts) is a very widely used small signal NPN transistor.  The most widely used commodity parts tend to be less expensive and are almost always in stock.  There's no easy way to learn what all the most common commodity parts are, so it pays to take notice when you see the same part used by separate designs published by different people.

But by far the most important thing is hands-on experimentation.  Building up your own repertoire of circuits you've personally built and experienced working is the path to long-term success.

Thanks Paul! I really like this idea of building up a personal catalogue over time through experimentation and being inspired by others! I love sites like this to get exposed to other's designs and preferences, especially now where makerpaces aren't necessarily an option. Thanks for sharing your ideas and experiences!

Hi @Thomas Countz , as you dive deeper and broader into different corners of electronics, you will be able to take more and more prior knowledge with you and be able to apply it faster and faster. But it can certainly be daunting to begin with.

I have found out about buttons I wasn't aware of by looking at the homemade Arduboy consoles on the Arduboy forum. They are also pretty good for OLED and other displays as people often need help with whatever they have decided to use in their build. The audio projects section of the Teensy forum has taught me loads about audio codec chips. They are just two examples of good places to go for particular things that you may not immediately associate with a rich source of good information. 

If I wanted particular part recommendations, I would ask here on the stack or hackchat. I had to give ST my email address to download their IDE and they now send me periodic emails with new products. They are below the threshold of annoyance so I have not opted out. Also, following hackers on hackaday.io will introduce you to new parts and applications that you could never dream of. I would pick Kris Winer, Ted Yapo and the student projects of Bruce Land as three to study and allow to open your mind. 

Thank you, Simon!

I'm excited to continue to explore the maker/electronics community; there's such a wealth of information here. Thank you for sharing some great resources/contributors to take inspiration from!

In the same note, I am signed up to TI's newsletter after using their Weebench Power Designer.
The newsletter occasionally throws some very interesting material my way, and the Weebench Power Designer helps a TON when designing buck/boost or similar power supply configurations, though it only uses TI parts.

But I agree a lot with what people say - dig in, get some hands-on experience, and maybe just gather a few parts that are your personal favourite :)

((Mine is a specific side-mount WS2812 clone LED, which I found to be great to put basically anywhere because it's much smaller but just as bright))

Samples. If you have a local parts vendor that you frequent, they'll send out engineering samples from time to time. Works really well when you have a business account.

Also, do what you do best. Tear stuff apart, look up the part numbers. ICs are easy, even the three character codes that are on SOT-23 transistors can be found online.

Samples sound really exciting! :)

I think doing tear-downs is a really good idea! Not just physical tear downs, but reading open source schematics from places like Adafruit and Sparkfun. That has allowed me to see how certain components are used in context. For example, I could go through all of the work validating a SMD button or I can try to find the one used in the Adafruit Feather and feel confidence that I could use it in similar applications.

Thank you for your reply!

It's not so easy to pick out parts! My approach tends to be to order way more stuff than I immediately need when I order parts. This way you can build a collection of parts over time. It helps a LOT to have a parts organizer to store them in. I like to use LCSC. It's incredibly cheap to order a lot of parts at once. One approach you may use is to search for something like "diode assortment" on eBay. Don't actually buy it there, just look at the diode values they have selected. This trick works with a lot of stuff like resistors, capacitors, etc. 

That's great advice, thank you! I recently ordered resistor, capacitor, transistor, and linear IC pack from Futurlec: https://www.futurlec.com/ValuePacks.shtml.

The list of parameters that you have looks about like what I use. I tend to deal with a couple of distributers (Mouser and Digikey) and if they don't have it, try to find a part/solution that they do have.

There may be a list of vendors that people have had good luck with, but I have never seen one. I generally avoid amazon and alibaba  and ebay for a couple of reasons, one being that it seems more likely to get counterfeit parts through them than traceable sources. When i was working, time was pretty scarce and knowing that I have good parts was more valuable than lower cost. Now that I am retired, I mostly have stuck with that habit.

Part status is one more thing to consider. Once you have designed someting in and have good schematic symbols and PCB footprints, re-using that part saves a lot of time. The early stages of that can be painful though. Projects that are going to be built more than 1 or 2 times add another layer to the availability aspect. It really stinks to get a project all the way through development and maybe production release and have a part become unavailable. That has happened to me a few tims in my professional career. The first tier vendors have a "Status" field in the catalog, "End of Life" (EOL) or "Not Recommended for New Designs" is bad news. It is funny, the stuff that goes obsolete on me is usually passive components like connectors, caps, and inductors. Chips are less likely, but you are really hosed then. The top tier distributers will email you if a part you bought in the last couple of years is going out of production.

Bob

Thank you, Bob! All of that is really helpful, especially your point about part status! I'm just beginning to build my first projects, but as I continue to grow, I hope to get to production-ize something at some point!

I imagine that once I find a component that works—take the push button, for example—I'll likely reach for that same component in the future (so long as it's available). At that point, I've already built the footprint and had some experience with it, so unless there's a design for which that part isn't right, I'll likely reach for it again and again.

That brings me to another thing I've found useful: looking at others' designs, like here on hackaday, for example. Seeing others use a component in a particular way gives me both inspiration and confidence!

With that, thanks for sharing!