Where To Find And Buy Electronics Components

Finding parts can be challenging even in the best of times, and with the pandemic’s parts shortages still happening, finding the parts you need can take a lot of effort. This article is a quick guide to parts resources I find helpful.

Components and Microcontrollers

If you’re starting out, Adafruit and Sparkfun are good choices for finding sensors, microcontrollers, LEDs and other parts. They both invest in extensive tutorials, libraries and other software, and both make most of their hardware open source. Both also have excellent customer service. All this comes at a cost, and they may not be the best choices for customers who are very cost sensitive. They’re a good source for components like microcontrollers and breakout boards, and not as good for discrete parts like transistors, resistors and chips although they do carry some.

If you need less support, Digikey and Mouser are both high quality providers. Adafruit works closely with Digikey, and you can find some Adafruit and Sparkfun products on both sites. Both also offer a vast array of discrete parts, too.

Be careful when ordering from them that you’re getting the parts you need in the packages you need - it’s easy to accidentally order surface mount resistors when you need through hole resistors, or a bare CPU or sensor chip when you need a breakout or development board with the chip already soldered on it.

Finally, both businesses do a good job of maintaining accurate information in their listings but sometimes the photos or information may not exactly match the product - I’ve accidentally bought ESP32 breakout boards with external antenna connectors because I the photo didn’t show the connector and I forgot to double check the part. Always review the part number and data sheet before you order.

Digikey and Mouser offer quantity discounts on most of their stock.

The Component Search Engine

Sometimes you don’t want to check several different companies for a component, or you want to find the best price for it. That’s a job for Octopart! Octopart is a search engine that reports on inventories of several different companies that specialize in selling electronics components.

Faster But More Expensive

If you need something soon, Amazon carries many Adafruit and Sparkfun boards, often at a sizable markup, as well as many clone boards and discrete components. Most are sold by 3rd party sellers.

Some sellers ship from China, which can take weeks, so be sure to double check where the shipment is coming from and how long it will take. And be extra careful to check reviews.

Slower, Cheaper, Worse

Very cost sensitive buyers may want to check out AliExpress. AliExpress is a marketplace - you’re not buying from AliExpress, you’re buying through it. They provide a directory of sellers and products, brokering sales and guaranteeing delivery and very basic quality.

There are many reputable vendors on AliExpress and I’ve had mostly good experiences, but occasionally you’ll find a vendor selling untested, broken parts. I had one order of BME680 temperature/humidity/pressure/VOC sensors which had the sensor chip soldered 180 degrees off from its correct orientation. Of course it didn’t work at all, but the seller hadn’t done even the most basic testing .

Many AliExpress vendors sell clone boards with cheaper or missing parts, as well. For instance, they may sell a clone breakout board with a sensor but skip the voltage regulator that makes it safe to use with 5V, or skip diodes or pull-up resistors. They may also sell microcontroller boards with different or cheaper serial chips than you expect. This is part of how you can get very low prices, but of course there’s still a cost for the low price.

You’ll also find vendors spamming keywords in product listings, like “nodemcu esp32 esp8266 raspberry pi Arduino” - what even is this product? This happens on Amazon and eBay as well. Just be careful to double and triple check what you’re actually ordering.

You’ll likely be fine if you order from AliExpress but if you’re just starting out and aren’t able to debug hardware or reflow a surface mount chip or figure out if a sensor works, they may not be the best source for you.

If you do order from AliExpress, try to stick with vendors that have made lots of sales and are well reviewed. This is a good plan for any vendor, but particularly in this case. Be prepared for it to take several weeks to a couple of months to receive your order. And when you receive your order, check it immediately to make sure you received the right things, and if you can, test them to make sure they actually work.

Good luck and happy component hunting!