[ GXB172 - 50W Single Cell 17mm Boost Driver! ]

I wonderā€¦.
I see more and more enquires about high voltage drivers. Hyperboost is the only solution out there.
I see that the IC here is rated to 90V output.
What would it take to turn GXB172 to a high voltage driver?

It is limited due to the IC it uses. It has a max voltage of ~16V IIRC.

So an entirely different IC would be needed and that basically means a whole new driver.

Ouch, I see that I mixed up different products. Yes, 16V limit. That kills the idea. Thank you for setting me straight!

Waitā€¦

Were you planning to use a COB?

As of now I donā€™t have any such plans. Now that youā€™re saying it - a flooder with 3000 lm CRI97 COB would be interesting. :wink: Though definitely out of my skills range.
I think Iā€™ve seen at least 4 inquires about it in the past quarter - and thatā€™s it.

Glad to see others have gotten this working, too! :slight_smile:

Thus far, Iā€™ve built a total of 4 of theseā€”two of the original Rev A and two more of the Rev A2. Sadly, I managed to fry one of the original Rev A boards, so I only have 3 operational right now. I am rather happy with them, but still would like to hack on the firmware a bit.

When I get a moment, Iā€™ll try to get some more pictures of the new builds, along with some measurements. However, I wanted to check in here and ask a question, as my fifth build is currently having some issues: after I power it up, it blinks the LED (at lowish power) 4 times before turning off. My guess is that communication to the temperature sensor isnā€™t working? But wondering if anyone else ran into the problem / how to solve it.

Iā€™ve got some of the 20mm boards (finally!), and will be doing some builds of those with some new S11 hosts from MTN.

(And yeah, I have had trouble getting my hands on the 47uF 25V recommended caps; 10V and 16V are fine for 6V and 9V operation, but 12V is too little margin. Managed to get a few from Mouser but they are since out of stock.)

Itā€™s been awhile back but I believe the very first one I built had the problem you described. I had used a small amount of solder paste on the 4 small pads and you can imagine what that did when reflowed with hot air with the pads being so small. I tried reflowing it again a few times and never did get it to work properly. I finally reflowed it off and cleaned the pads of any solder, used a brand new temp sensor with just flux on the pads and reflowed. That fixed it. Iā€™m pretty sure it gave me the same 4 blinks then off until I reflowed the new temp sensor on with just flux. I would try replacing the temp sensor or try reflowing the installed one again, maybe giving it a small tap on the top of the head when the solder reflows to get all 4 legs seated. I know itā€™s a pain being so small but thereā€™s not much else you could do besides replacing it and try again.

The last 47uF 25v caps I purchased came from aliexpress. They were considerable cheaper for the amount I received. They may not be of the same quality and I havenā€™t used any yet. But I did measure a few at 40 to 42uF. I do need to try out a few before I could recommend them. If they can hold up under the voltage they should be fine.

Let us know if this fixes the problem. :+1:

Can you connect two small wires and let it float or sit somewhere else?

Might want to tone down the cussing, it is not allowed on this site.

That said, having been working off and on with another member for a driver like this, I can tell you that getting this working at all is WAY harder then it sounds.

LO did an amazing job to even get this driver functioning at all.

I also spent well over $100 on components for the testing and prototyping of drivers based on this IC :person_facepalming:

Sorry, deleted comments I shouldnā€™t have posted without giving myself time to cool off and think clearly (and phrase things far more politely).

:+1: donā€™t forget itā€™s just a hobby

I wonder if more people has build this driver for themself? Maybe with firmware avalible for all, we can create some improvement which people have requested, but I do not have enough skill to make modification with open firmware and currently I am happy with basic firmware.

Schoki has been working on a version of this driver that would use a ATtiny85 MCU and thus allow normal BLF firmwares to be used on it for some time now. He has been super busy recently though so not much progress has been made.

Sooner or later someone will get it to work with BLF firmware. The only real question is how small will it be?

How sweet it be to have this driver running Narsil or anduril, thatā€™s like putting icing on the cake.
Thanks for the info TA. :+1:

the loneoeans firmware is on github on the gxb172 website, so I am thinking if anyone here has skills to modify it to work with narsil or anduril firmware? I will also like to try it with my build to see how we can make it work!

The issue is his driver uses a different MCU then we normally use. So narsil / anduril / bistro would have to be converted to work on a different MCU.

This has been discussed for years but nothing has come of it yet and when it does happen it will most likely be for a more modern MCU option.

Actually TK is working on porting Andruil to Attiny841 and Attiny1634. :+1:

Actively? I heard she was wanting to work on it a long time ago but never saw anything come of it.

If it is happening that is great to hear. They allow for some interesting changed to driver design due to the smaller footprint and extra pins.

Attiny1634 is already working though the code is not published yet. :slight_smile:

Very interesting, I will be curious to see how that progresses.