How TINY Can I go? The BEST Power Board is here!

In this project I will try to remake an AliExpress PCB. It is a very handy voltage converter that can take a varying battery voltage and convert it into 3.3V or 5V while only requiring very little current (25uA) on the input. Sounds awesome, but the board is way too huge. That is why I try to push the size limits in this video to the minimum. Will I succeed?? Let's find out!

Websites that were shown/used during the video:

Thanks to the Würth Elektronik for supporting this video.

0:00 This Board is TOO BIG!
1:31 Intro
2:15 What Components to use?
5:02 Making DIY Version 1
7:08 Testing Version 1
8:35 AliExpress Board Comparison
9:10 Making/Testing Version 2
9:58 Making/Testing Version 3 (Tiny)
11:04 Verdict

[greatscottlab]

Important! My own designs here were not EMC tested. I will explore that topic in a future video ;-) There we will see whether my boards follow guidelines and how we can possibly change the design to make that happen. Also we will test the Ali Board as well concerning EMC. That will be fun. I hope you are looking forward to that ;-)

[FreeOfFantasy]

Another idea to get it even smaller: This is a non-isolating converter, so you don't need a GND pin at output. That enables you to just put all the contacts on one edge. GND in the center, and capacitors on the sides in between. I bet you can make it smaller if you place more components on the backside too, but for manufacturing all components on the same side are prefered.

[kurtnelle]

That is the cutest reflow plate I've ever seen!

[hufca]

Experienced engineer here... Looking at your PCB design i noticed that you make so called via-stitching equally spaced, which is a bad habit. Especially in fast switching circuits. That's because those places often become nodes of the high frequency standing waves, which in result amplifies the noise, energy loses, and destroys the electromagnetic compatibility of your circuit.
This is quite unintuitive, but randomly placing vias (which for an untrained eye may seem unprofessional and ugly) in fact makes your circuit better!

[bencemarta]

Nice little chip. I have considered using it for backup power for some home-grown smart home devices but ultimately didn't go through. I missed one thing from the video though, that can make or break a power supply and that is capacitor derating. Class II ceramic capacitors are pretty nasty and change their capacitance if they are DC biased and me not taking that into account actually cost me weeks of troubleshooting because of unstable power caused by the lack of capacitance at the input. TI has a pretty nice online design tool that helps you find derated values and most capacitor manufacturers have a public database.

P.S. Thanks for reminding me about this IC, I have a project where it should serve me perfectly

(Edit: corrected grammar)

[BigBoyDuckie]

While browsing TI's product page for the TPS63020 I came across the TPS631000, which TI itself describes as 'Upgraded product with 8-uA IQ and smaller SOT package.'. It would be really cool to see you make a board design using this chip, especially since i couldn't find any boards using this IC online.

[nil]

Pcb designing for switching converter is actually pretty intense and interesting
The way you place your current loops become very important

I recently did first attempt at pcb designing and have it fabricated
( Not good but usable)
Useing kicad

I highly recommend Phil's lab vids if anyone wants to know more about it

[satyamedh]

I am designing something that does use this IC, I have never designed anything of the kind before and this video was indirectly a great help


ty man

[samfosteriam]

This was very timely for me. I would love to see the lipo charging ic built into a tiny board like this - that’s something I need for lots of small projects

[BRUXXUS]

Wow! That’s amazing! Also, those inductors are incredible for their size!
I’ve been working on a PCB which needs to put out 5V with as much current as possible, as small as possible, which runs on a single 18650. I ended up landing on a TI chip as well that’s just amazingly small for the power it can handle.

It’s a fun challenge!

[jameswoll]

I would love to see more miniaturization videos! This was great.

[DonaldDuvall]

I am amazed anyone can solder that tiny, i for sure cannot. Good video as always.

[MathewPanicker]

I really like these old school circuit design videos!

[mikefrachel]

The only pcb I've seen that makes that hotplate look big!

[michaelcarey]

Excellent work! I try to use thinner PCBs for smaller projects. 1.6mm is fine for large boards, but small PCBs look "nicer" when they are thinner 🙂

[ObsequiousV]

That giant wurth elektronik case of parts looks amazing.

[blakeshafferfilms]

I didn’t get a good look at your layout, but adding some additional ground layers in the middle of your board can help with reducing output ripple. It is also helpful to “isolate” the feedback node by ensuring the feedback trace is thin and doesn’t go anywhere near the switching node. Same thing with the ground reference for the feedback divider, have it be a trace that goes straight to the return of the chip and ensure the power paths are “separate” if that makes sense. Great video! Thanks for sharing!

[xTerminatorAndy]

Thanks GREAT Scott. I like this video, just like all the others you have made. You and Captain Dissolution are 2 of my favourite creators

[Conservator.]

Multiple different size (and or type) capacitors are better at filtering noise than just one large one. Inductance might also play a role in choosing multiple capacitors.

[marshallpennington]

Hi Scott! I know I’m a bit late to the video but if you do end up seeing this and you would like to try using smaller components like 0402 and don’t want to pay for a metal stencil from JLC I would recommend getting some thin Mylar that is about double the thickness of a zip lock and a bit stiffer and then using a laser cutter to make a stencil by importing the easy eda stencil files into its software. I use this all the time for rapid prototyping and it works great even for panels