Has anyone modded a H1-A boost driver?

I would be in for two with DavidEF’s variation, or just the mode memory at the very least.

Ehm, we are talking about a clicky driver David, how do you see direct access to high and low from off happening?? And I expect with this hardware and no ToyKeeper around at Kaidomain I fear that a requested custom UI can not be too complicated.

Perhaps my favorite UI will round up fewer people than some other UI, but of course my motivation to start this is based on me wanting my favorite UI, so someone else should start an interest list for a different UI. I will just keep my list going in post #24, see what happens…

Ehm, double click? :innocent:

EDIT: Oh, and ToyKeeper is looking for a job, so…

1% - 6% - 36% (- 100%) mode spacing, I like that . Would also like some other sort of variable exponential driving current discrete set like: 0.03% - 11% - 33% (- 100%).

Mode memory seems fine as it is to me, last mode memory or whatever is it called.

Custom UI requests for a small fee could be a killer feature, at least for a given minimum of features: spacing and mode memory.

Not joining the party for now, would be quite unwise given my current financial situation.

^:)

Originally posted on Fri, 04/21/2017 - 14:30; typo fixup.

Just got my H1-A and H2-C drivers 2 days ago. Looks like the MCU is a PIC 12F, same as the FX30 driver that the L6 uses. So custom UI programming should be possible if the drivers were reverse engineered to determine the pinouts. Just need the PIC programmer. I just happen to have a Microchip ICD3…

3.3% - 11% - 33% - 100%
O well…

Well that was 4 weeks ago and they just tell me it shipped out today, 5 weeks later. :person_facepalming:

Apparently they sold out, but didn’t tell anyone.

I added an R100 resistor on top of the existing R025 on the H1-A, current is up to 3.5A at the emitter.

This is up from the stock 2.75A at the emitter I measured before the mod.

Testing was done using an electronic load set to 6.2V constant voltage mode for the emitter, and a bench supply set to 3.7V for the battery.

I forgot to look at efficiency before the mod, but it isn’t great after at about 70%. This is with fairly long test leads though. I wouldn’t push it any further than this personally, the inductor gets hot fast, and it was pulling almost 9A from the bench supply.

Nice info, Jensen. Thanks!

Been there. Not a word or info about not having any.

Jensen567, I'd like to take a good look at more rigorous testing conditions. Even with good high discharge cells like the LiitoKala 26650-50A, input voltage at the driver would be below 3.7V pretty soon: with about ⅓ of the capacity left, Vbatt barely is above 3.3V with a 10A load. Source:

Those efficiency figures seem pretty bad.

Cheers ^:)

I can run more tests when I get a chance, this was mostly just to test the resistor change, and emitter numbers are accurate as they are regulated.

There were many input losses, with 3 ft 16AWG to each lead, the positive was an alligator clip on the stock spring (close to base), negative was an alligator clip held on the edge of the driver with my hand. So high connection losses. I will tack wires on for the next test. Also need to do the H2-C.

Keep in mind that even when the battery voltage is low, the output at the led is just like a fresh battery compared to a FET or CC driver where the light dims as the battery voltage goes down.

But yeah, 70% is kind of low in general. It’s probably like Jensen567 mentioned. With better connectors and shorter wires, efficiency will probably go up.

I am a beginner when it comes to buck and boost drivers, but I think the inductor causes a lot of the losses. The small ones that come on these drivers can have almost 0.1 ohms resistance, so with almost 10A that is a lot of heat.

When my H2-C driver arrives I’m going to experiment with replacing the inductor with a bigger, lower resistance one.

I have to agree with EasyB. This is how a driver with a properly sized inductor (and an oversized schottky diode) looks:

Cheers

Ha ha, I guess you can use one 26350 battery to make room for all that. Lol

The inductor is definitely going to be the limiting factor, it basically always will be in a compact buck or boost driver. That said, these little drivers aren’t too bad!

Ran some new tests on stock and modded drivers with 4 wire input and output to read voltages at the board this time. My temp numbers aren’t perfect, just a thermocouple held onto the inductor, but decent ballpark. There is also no heatsinking at all, driver is just in open air, no fans.

H1-A Stock:

Input 3.58V 1.72A outputs 6.26V 0.94A, 95% efficient

Input 3.27V 6.11A outputs 6.37V 2.82A, 90% efficient, temps hit a bit over 50C after 2 mins.

H1-A with R100 added:

Input 3.54V 2.19A outputs 6.30V 1.18A, 96% efficient

Input 3.07V 8.71A outputs 6.48V 3.52A, 85% efficient, temps hit around 75C after 2 mins.

Based on the efficiency drop I think the inductor is saturated, this is probably as high as we want to push with a simple resistor mod. Overall I am very pleased with this H1-A.

H2-C results below are not accurate due to an unknown malfunction of the driver! New results in later post.

H2-C is not as good, or resistor moddable. Comes stock with 2 R100 stacked, I added a third R100.

H2-C stock:

Input 3.51V 2.62A outputs 12.45V 0.65A, 88% efficient

Input 3.29V 5.45A outputs 12.49V 1.10A, 77% efficiency, temps hit around 65C after 2 minutes.

H2-C with R100 added:

Input 3.39V 4.14A outputs 12.46V 0.99A, 88% efficient

High mode showed no change, output current actually went down a tiny bit to 1.06A. Tried lowering the output voltage, still no change. It appears a bit over 1A is the limit without more extensive modifications. I went back to stock resistors so the lower modes stay lower, as they did all move up despite no change on high.

Bigger inductor would probably help, and is certainly possible on both drivers, as the SMD inductor is on top of other components, connected with a large solder blob and jumper wire to the board, it does not sit on the board at all.

Thanks for your extensive measurements!

Now combine this with an XHP-70.2 to get an extremely efficient flashlight!

Well, I was going to make a comment with regards to the huge losses entailed with 6ft of AWG16 leads carrying 9A of current and the alligator clip contacts, but thanks for taking the time to read the voltage at the boards' input terminals, the figures make sense now.

Oh! If you need for these drivers to handle more power, upgrading the inductor is doable. On my above example, I literally milled the onboard one with my multitool, as desoldering those heat-sinking chunks of copper among the remaining board components can be tricky.

Jensen567, now that you're in, could you please test the maximum output voltage for the H1-A?

I ask this because with the newer configurable triple 3535 boards at Kaidomain, an in series configuration may be feed with a suitable boost driver.

Cheers ^:)

OCV on the H1-A output was a bit over 7.3V, so not really suitable for 3S emitters unfortunately.

The H2-C would probably work with a triple emitter setup, I will try this afternoon to see if the output looks better at around 9V than it did at 12V, because it was fairly disappointing at 12V.

Yes, 6ft of 16AWG on the input, and 6ft 16AWG on the output with alligator clips certainly leads to very high losses. Numbers definitely make much more sense and look better when taken at the board. I went from, eh, it’s OK, to wow, for 12 bucks this thing kicks butt.