DC DC general info BOOST + Buck Boost Converter

I expect them to kinda suck, so target usage in the 50% of rating or lower. I wouldn’t mind if they only lasted a year but lasting a few microseconds is a but hard to justify :joy: good thing they are cheap. I just can’t find anything more conventional or conservatively designed that works with higher voltage packs and my attempts at diy have not been productive. ¯_(ツ)_/¯

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I’ve got mine heat shrunk inside of an enclosure, I’m only running 2 bluetooth led controllers and 2 leds strips with 28 leds ea.

Poop, popped the 4th one. Not sure what im doing wrong here. Maybe it needs the io signal off before connecting power and can’t be wired always on? Load is a single 25mm fan running at 100ma. Didn’t think i was doing anything strange here but it doesn’t have power except when a charger is connected idk

Inline tvs diode? That worked for my buck converter

Have a part number for what you used? From my googling: I would place it in parallel to the input voltage and size it by its voltage breakdown (so 80v) in this use?

https://assets.nexperia.com/documents/data-sheet/NUP1301.pdf \

something like this or is there a better form factor or spec?

The one i used was like this and it went between the positive and negative input on the buck converter

Went with the p6ke91a. 77.8v clamping at 125v so it may work but the 125v clamping voltage makes me think it might not work. Everything that had 100v or less didn’t have a working voltage for 18s. Trial and error time

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Dude, you really need to wire them the way they are designed.
You need a 5v source to “enable” the circuit.
You admitted you were using full voltage to “enable” the circut.
That’s not what these are designed for.

I have close to 10 of these in different boards in the wild and have had zero failures.

I see no reason for you to keep complaining that these are failing, you keep wiring them wrong.

Wire one up properly and watch it work the way it’s supposed to.

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Can you see the part numbers on the main controller chip on the pcb? We can check if the enable pin can be toggled via the input voltage or if it needs to be logic level, typically 5V.

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When i get home this eve, I’ll look and see if it’s printed on the chip. On these photos, it really doesn’t help.

I must have misunderstood the label on this?

I figured input positive terminal meant the input positive terminal adjacent to this terminal but the output positive is also labeled input positive and i missed that. Ill set up the bread board and give it a go. But i am developing trust issues

Also i only did this on the 5v buck. I was going to use the 5v from the buck to switch the 12v on and off to turn the lights on and off so i could use a cheap small switch. Im nervous about ties between the esc 5v and this thing breaking my esc. When i had the 12v buck i tried to use the esc 5v to power it on and it died - i got hesitant and changed up my plan to use the 5v from the buck but all of the ones in my original order are dead. I have 2 more of the 12 and 5v to mess with but im not holding my breath. The tvss diodes just got here and im gonna just build everything without connecting anything to the esc for now

how to adjust dc boost pot

Final batch of these to try, put a tvss diode across the input and it seems to be lasting significantly longer. Load/no load, switch on switch off, load odd switch on all the different iterations seem to be good on the bench now. Moved it from the bench to straight 12s juice and ran through all the different combinations of power, switch and load with a sacrificial flipsky 5v to power it up and it seems good.

Next ill try it on 3.3v and 18s voltage and see what we get longer term

Edit: 3.3v seems to work as well wich opens up the possibility of using the zmote receiver to control diode without a logic level shifter so bonus

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Got some 5v and 12v versions of the nice n cheap buck converters @Soflo and you said you have used a bunch. These 12v one have a fluttering voltage, as in it is making the lights flicker. The 5v ones seem to be working perfectly fine but the 12 is seizure inducing. Any experience or tips?

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I only used the 5v output ones

The guy i was help build this for is using an old flipsky so maybe that has something to do with it? On the bench power it seems to work smooth but output voltage has that weird flutter and is showing 10.8vdc on two separate units. Maybe 5v from the uart port is doing something and not fully turning it on or something? After seacarve im going to redo my lights so i can use the zmote to turn my high beams on and off which are 12v so ill have to figure something out. Give my solos’ 5v a chance to try switching them