Buck and Boost Drivers, Testing, Modding, and Discussion (Pic Heavy)

I didn’t had much time this afternoon. Guess never mod when you are in a hurry :stuck_out_tongue: But a trace on the backside (close to the spring) was completely burned. Did a bypass but now the driver pulls 10 amps (at the battery)… no change in output when changing modes. But I still got the flashing mode…

I have a KX70 driver that has been modified exactly as Jensen567 had detailed, putting on a 2.8V LDO, moving the cap, with .01875 sense resistor. Everything seems to be working, except for one thing. The driver doesn’t fully turn off. The momentary goes through the modes using 1 press per switch, and it doesn’t seem to cycle off, so I hold to momentary down, and it seems to turn off, except the led (XHP70.2) is slightly lit, almost like a moonlight mode. Is there anything I’m missing?

Just ordered a new h2c driver.
But I got a quick question. Is this the sense resister?

Yes. :-)

FYI, just ordered a few recently and seems like small revisions. Old on the left (few months ago), new on the right.

Looks like an H1-A with downgraded inductor (?). I wonder how much of an actual impact that has when increasing the current/power output near the TPS61088's integrated switch current limit (10A). Thumbs down of course.

Yeah, I wasn’t sure either, was hoping someone here could tell better than I could. Haven’t dropped it into a light yet.

Can the H1-A be modded to add a remote pot for dimming?

Hopefully this thread is okay to cross post this question.

From FT03 thread. ” “Is there a driver swap you can do that has a v booster?”“:Review: Astrolux FT03 Thrower - 2400 lumens / 900 meters - #23 by TeeDubya

It list a ‘Texas Avenger FET Driver with charging’ as a driver. I basically wanted it to run like the FT02 did if possible.

We are still a ways off from having universal boost drivers that can run NarsilM or Anduril or just an E-switch in general. You will also loose the charging.

The few universal boost drivers out there are limited to whatever brightness levels and UI it comes with. I am still waiting for better drivers.

Universal? What do you mean by universal? For universal things to exist as a rule most people would need to develop its consciousness and themselves a good deal more.

NarsilM? Anduril? What gives? I Hi-Lo-Strobe :-D LoL.

In all honesty, using fantasy names for microcontroller software may sound compelling for the freaks. For people outside of these circles, definitively not. I've been around here for some time already and I've never used a torch with software of that class, for example.

I would choose a descriptive term. For example, Advanced Multifunction Flashlight Firmware vX.Y.

Of course I have to admit NarsilM or Anduril are terms which completely fail to inspire me. I prefer DynamiteBundle or BonnyC4Piece instead.

I mean like the same driver design available in a variety of sizes like 17mm, 19mm, 20mm, 22mm, 26mm, 30mm, 46mm. Maybe the bigger drivers have more power, but the basically the same design.

This is what MTN E and Lexel are working on. A good boost driver design that can be made in multiple sizes using an e-switch and some nice ramping firmware. Lexel is working on Anduril and NarsilM while MTN E uses RampingIOS.

MTN E has released a few sizes of his boost driver, 17mm, 20mm and 22mm, but they are not ready for e-switch, yet. Lexel has not released any of his yet.

I am not interested in tail clicky, Hi, Med, Low designs.

A potentiometer is like a variable resistor. The firmware in that driver looks for a brief loss of power (it uses a capacitor to keep it’s MCU “clock” running for a few seconds) to recognize when to change brightness levels. So it is two completely different things.

I can’t say for sure as I haven’t tried it but adding a pot would probably have to be done using a PWM circuit controlled by a pot.
I have used this simple 555 timer circuit a few times to add pot controlled PWM to circuits that accept pwm input.

On the H1-A, cutting the trace from the PWM output at pin 5 on the MCU and adding the circuit above with the pot controlled pwm output tied to the the cut trace might work. At least that’s how I would try to make it work.

So could the 555 timer circuit be added to a cut pin 5 trace for variable brightness or does it not apply to this circuit.
I think you have a little more electronics back ground than me, that’s the reason for asking.

Thanks. Don’t mind loosing charging but the UI is a pass for me too. What’s the sticking point for those working on making them? To a complete layman? Keeping the voltage boosted while all the possible clicks/outcomes?

This is what I had in mind, and also would like to know if it’s possible with this driver.

I really don’t have much of an electronics background. I know a little about FET drivers, but just the basics of Boost and Buck

I know some boost drivers are designed to accept pots to control them (like this one), but the HA1 is not one of those. I believe your talking about cutting the PWM output trace to the OPA333 and adding a new opamp that can be controlled by a potentiometer. Maybe it can work? It is beyond my knowledge.

Such dimming would be very helpful for my application. The H1-A fills a huge void for when having to operate 6v LED with 1S batteries. There are few to no other options.

My application is a bike light, specifically a IQ-XE light. The unique efficient design has the best cutoff for no glare onto oncoming traffic without losing lumen. But the design requires the use of a double LED encased in series in one tiny unit (OSLON Black Flat KW H2L531.TE) nominal 6V, 1.5A peak, and this light operates at 0.9A max.

The driver in this light is inefficient and could use a boost in output. It also requires 12v input and I want to stick with 1S batteries without having to deal with balancing. So I gutted it and added the H1-A driver. I modded the H1-A to operate at 1.2A and I got much more output at the same net energy consumption at the battery, and with 1S. So I was very happy, until my shoddy soldering work failed. So I’m attempting it again with another H1-A.

My application doesn’t require the driver to fit within any confined space, but it does need to be lightweight, and the H1-A is perfect. It would be nice to explore dimming options with a potentiometer (555 timer?). I came across another driver I’m curious about which seems to operate on the same principles as the H1-A, using a XL6003 IC. The particular driver doesn’t have dimming but the IC supports it. I don’t know enough to know how the design compares to the H1-A.

https://www.aliexpress.com/item/32918936790.html?spm=a2g0o.productlist.0.0.5df55ee0VkHvUr&algo_pvid=fa12217c-7f1a-46c2-92c2-4e75097f2dba&algo_expid=fa12217c-7f1a-46c2-92c2-4e75097f2dba-0&btsid=15072488-fcb8-4cea-b054-c20cc0282ef7&ws_ab_test=searchweb0_0,searchweb201602_5,searchweb201603_52

I just saw you link to the hyperboost driver. That just might be the ticket. I’d have to give up on 1S for that driver and go with 3S. I’m considering it.

Edit: hyperboost won’t work with less than 8V.