Low Cost Buck Converter for Esk8

Ive seen a lot of people looking for UBEC’s or other step down converters for there boards, to power things like LED’s, USB Chargers, etc. Problem is most of them are expensive and output at 5V and/or are not built for Esk8. I was looking around for something like this to power a set of LED lights, and I couldn’t find any good options. So I decided to look into creating an HV step down converter. Eventually I came across the LM2576HVS-12 Simple Switcher which takes anywhere from 4-60V input and steps it down to 12V at a max of ~3A. I put together a parts list and some schematics for building something like this and the price per piece came out to only around $1.50 per module, buying in semi-bulk. Ill provide a BOM and schematics once ive sorted it all out completely, but I wanted to see if anybody would be interested in something like this, either for building themselves or for purchasing one fully assembled. And please drop any questions, comment or concerns below!

GitHub Repository

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Why 12 volts ? I thought led’s run at between 2-5 volts natively and need to be tuned to the right voltage with a resistor anyway. I don’t really know what’s more efficient

https://www.ebay.com/itm/381807336269

This would be for LED Strips or LED Lights that normally run on 12V.

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Most LEDs have a forward voltage of 1.9 - 2.0 V. You can string 6 together in series and run them off 12V without a resistor. I plan on doing that for my tail lights. My headlights are 12V already and are very very bright

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Hey @Michaelinvegas thats actually very interesting because I hadn’t seen anything like that before. Though like I said in the main post, it isn’t necessarily built for Esk8 and it costs $6.29 shipped, while mine would cost just around $1.50 per module.

Be careful doing that though because the first LED in that string will be carrying the current of all the other LED’s in said string and it can die prematurely due to higher current. That works fine if your doing it in just short chains, but for longer strings, its better to have separate smaller chains of LED’s.

Just curious, why does it need to be specifically “built for esk8”? An LED doesn’t care whether it’s on a skateboard or not :wink:

The lower cost would be great though. My 12V 3A BEC was like $15 shipped from Amazon, since I didn’t want to wait for it come from China

They are in series, so every LED in the loop sees the same current

Hey I’ll take 5 at buck fifty … as long as don’t gotta put it together lol

Yeah I know that kinda sound stupid “Built for Esk8” lol. What I meant more of was its built by people in the community so you can have more support because you would be talking directly to the creator or whatever, instead of some guy in China using the crappiest google translate software out there.

Ahh your right sorry lol, I guess I was thinking parallel, woops.

I’ve used this one. and these too

I think this is pretty similar to the lm2576hvs. but adjustable output. I have a few they work ok but they dont recommend more then 30V difference.

Yeah uses a very similar IC. Though that one is still $3.11 so building this one would be cheaper, but that is definitely a good alternative. I was more looking to see if people were interested in this, and possibly building one themselves, if there into that, then really finding the cheapest option.

I bought 10 so its only about 1.5-2 each. are you sure you’re counting pcb and time to build them?

unless you add in something like led driver, switch pins…I don’t think it would be worth it. they are very similar.

If your building this on like perf board, then there goes PCB cost pretty much lol. And Like I said this is mainly for people who want to build there own and get the experience. Though i definitely get were your coming from.

Yeah I find the adjustable ones can’t handle dropping the voltage down…that’s why I just get the one with a fixed output …that’s not perfect either but it’s closer to 12v output at 13v

yea perf board takes time tho. it is really simple just 4 caps, 1 diode, 1 resistor, 1 pot, 1 to package.

@Michaelinvegas this one seems to hold output voltage constant, just gets hot bucking 12s (50v) down to 12v… should work fine with 6-8s.

Also have you used that LM2596HVS at more than 40V because I cant find a datsheet for the LM2596HVS, so I was thinking it might be a re-branded LM2596 which can only handle 40V.

no its a high voltage version. works for up to 60v. I’ve used on 12s fine. I’ll test it a bit more to see how warm it gets.

Well do be careful because ive seen some videos were right when they get to about 50V the thing stops regulating… so yeah, heres the link https://www.youtube.com/watch?v=JLwJb4MVbls

Yea I saw that video, seems like a bad batch. I don’t have an adjustable supply that goes that high so I just tested with 12s pack.