Has anyone modded a H1-A boost driver?

Driver is nice, it is running an xhp50.2 on my convoy L2 and performs very well. I’m looking forward to seeing boost drivers on the market

Let’s hope they make a 17mm version

How is the memory working for you? Annoying or usable?

usable, it starts on last used mode (if you let that mode for 3s before turning it off)

hmm, 25 or more….
I know that so many people have so many preferences, so I’m pretty sure this is not going to work, but:

Say I ask Ban for 25 drivers with my favorite UI: 1–6–36–100, always start on lowest with no memory. Would it be possible to get 25 people wanting this enough to pay the extra $1.80 for the envelope and stamp to send it from me to them?

I will just start a list here in post #24, who knows how far we get…. :

1) djozz
2) djozz

Well, I prefer to have mode memory, even though I don’t actually use it much. :person_facepalming: Also, I definitely need direct access to the highest mode, especially if there are 3+ modes. If you can get direct access to both high and low from off, and a mode memory toggle, so the end user can choose, you probably won’t have any trouble getting 25 drivers sold.

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: