Ok, I’m ready. Let’s do this! Here’s my experience with sourcing MOSFETs from Digi-Key.
Alright, so here’s the deal. I needed some MOSFETs for a little side project I was tinkering with – nothing too crazy, just a simple DC-DC converter. First thing I did was head over to the Digi-Key website. I mean, where else would you go, right?
My initial search. I started with the basics. Typed “MOSFET” into the search bar. BOOM! A million results. Okay, time to narrow things down. I knew I needed something that could handle at least 30V and a couple of amps. So, I started using their parametric search. That’s where things got interesting.
I began to filter by voltage and current ratings. Then, I thought about the package. I wanted something easy to solder, so I looked for through-hole options. But, dang, through-hole MOSFETs are kinda getting rare these days! Ended up deciding on a more common SMD(Surface Mount Device) package, specifically a TO-252 (D-PAK) ’cause I had some experience soldering those before. Not my favorite, but workable.
Next up: figuring out what kind of MOSFET. Was I after an N-channel or P-channel? Since I wanted it on the low-side I picked N-channel MOSFET to keep things simple. Added that filter too. The number of results went down, but still too many to look through manually.
Digging Deeper. I started paying attention to the other specs: Rds(on) (drain-source resistance when on), Vgs(th) (gate threshold voltage), and Qg (total gate charge). The lower the Rds(on), the better, because it means less power loss. The Vgs(th) needed to be something reasonable so I could fully turn on the MOSFET with my circuit voltage. Qg, well, lower is also better here, meaning less charge needed to switch it, translating to faster switching and less driver power.
This is where I spent most of my time, reading datasheets. Seriously, datasheets are your best friends. You HAVE to look at them. I was comparing different MOSFETs, trying to balance Rds(on) with Qg and price. Found a couple that looked promising.
The Final Choice. After comparing like five or six datasheets I settled on the part number. It wasn’t the absolute best in every single category, but it was a good compromise between performance, package, and price. And, importantly, Digi-Key had it in stock! That’s always a win.
I added it to my cart, double-checked everything, and hit the “Place Order” button. Easy peasy.
Lessons Learned. Here’s what I took away from this experience:
- Know your requirements. Voltage, current, Rds(on), Vgs(th), Qg – you need to know what you’re looking for before you even start searching.
- Use the parametric search. It’s your friend. Learn how to use it effectively to narrow down your options.
- Read the datasheets. Seriously, read them. Don’t just look at the headline specs. Understand what they mean.
- Consider the package. Make sure it’s something you can actually solder!
- Check stock! Nothing is more frustrating than finding the perfect part and then discovering it’s out of stock.
Overall, it was a pretty smooth process. Digi-Key’s website is pretty good, and their parametric search is a lifesaver. And yeah, now I have MOSFETs ready for my DC-DC converter! Time to get soldering!
