Q8, PMS SEND TO THOSE WITH ISSUES BLF soda can light

Not just MZ, but there would be less beam color separation with most other LEDs too - OP reflectors always give smoother, more uniform beam which is important for high CRI builds.

I am very interested in a 3x18650 light and mentioned it in an interest thread a long time ago. The smaller diameter and lighter weight will make it easier and more likely to be picked up and put in my pocket. The 3 cells will allow for very good runtimes and being larger than a single cell light, it should handle heat a bit better. People with smaller hands might prefer it as well.

There have been a few 3x18650 lights released and the Firefly seems to be a success, but it costs quite a bit more than the Q8 does. I don’t care about usb charging at all and would prefer to not have it because of waterproofness if the port is covered by a small rubber flap or plug. If its hidden by the threads, I might like it more. It would have to be a solid design and one that would not add too much weight or bulk or cost for it to interest me.

Yeah, sounds good to me. USB charging would be fine if not slow. 3 18650 would fit the hand better than 4.

One thing to consider re: LVP with an e-switch:

It’s possible to get a dpst swtich, so you have one pole that “bootstraps” the MCU by turning on a transistor, and then you have the other that is used purely for click detection. It may even be possible to do this on a spst switch with some electronics trickery. When the MCU detects i’s below X volts, it sets the pin holding the transistor to “off” and the whole thing goes totally dark. No power until the button is clicked again.

Hardware wise, it would be best to use a mosfet to minimize quiescent current, and make sure to use very high value resistors for the “on” signal to the mosfet. Given the relatively high capacitance of the mosfet gate, you might even be able to get away with putting a capacitor on the line to hold it high, and just give it a periodic pulse to maintain voltage when in sleep, if you desired to keep the MCU running.

Have you measured the power used by the Q8 driver during standby, or after LVP activates?

In stock form, with the button LED off, standby drain is about 0.02 or 0.03 mA. Or after reflashing it with different fuse values, it’s even lower. If I recall correctly, it was something like 0.00002 mA. And with four cells, divide all these values by four. This makes the standby power virtually indistinguishable from zero, because it’s lower than the cell’s self-discharge rate. With the right fuse values and with the button LED off, I’ve found that I can actually take the battery out for a few minutes without making the MCU shut down. And it can still wake up on button press.

Atmel calls this “picopower”. It makes standby mode use such a small amount of power that it’s not necessary to design in clever power-disconnect circuits.

Yeah, I’m not suggesting it’s necessary, just providing input. I think it might be more relevant given a driver that couln’t use the super-low modes on the MCU or for a non LiIon battery. (AA Emergency light, for example).

That’s a super neat anecdote on pulling the cells!

BTW, I’ve been studying the FSM code for a potential MCU port, well done on the organization! I’m still picking up C syntax, but overall it’s very readable for me.

I wonder if there is a market for protected cells that only have LVP rather than LVP and over-current.

Oh yeah, it slipped my mind that USB is only 10 watt (2A@5v) at most. This would make it very slow if you were charging 3 or 4 batteries.

USB-C might be the better choice. A few flashlights already use this. It’s capable of 60W (3A@20v). So maybe the internal charge rates could be 1A to 1.5A per cell. That would greatly reduce charge time.

One problem I see with built in charging in general is that the Q8 can run on 1, 2, 3 or 4 cells. If the charging circuit delivers 4A@5v (1A for each of the 4 batteries) and you happen to be running only 1 battery in it, all 4A will go to the single cell and lead to disaster.

Which MCU?

I’ve been considering porting it to tiny841 and tiny16something, to get more pins and potentially also more ROM. But I probably won’t for a while.

The jankiest Ukrainian? MCU in existence that they used in the MF02s. If I can find the time, it will be less of a “port” and more of a controlled demolition onto a new chip. Basically it would involve taking any of the references to atmel libraries plus any of the assumptions about timers and subbing in a compatibility library or something. I’ve posted a few findings in maukka’s MF02s review thread. Ultimately I don’t have a lot of hope, but it would be nice to do, as the driver is a quad channel boost driver running the XHP70.2 at 12v.

Actually USB Power Delivery (which uses Type C connector) allows for 100W, 20V 5A.
There are laptops (and adapters) on the market already which do (from memory) 95W.

Type C without PD is 5V 3A.

Yeah, but I’m talking about the more common USB-C. 20-30 watts seems the most a charger would need.

I still don’t see it working well on a multi cell flashlight unless you were to limit it to 5 watts total. That’s 0.25A to each of 4 cells and a very slow charge. I think that’s the real issue.

Has any parallel battery light had a charger circuit built in? If so, I wonder how they dealt with this issue.

I think USB charging on a multi cell light is just a gimmick that is best avoided.

It adds unnecessary cost, is just something else to go wrong, & allows for water intrusion unless put in the threads…. protected by an o-ring.

ymmv…… :wink:

Oh yeah, it would be slow…. Worthlessly slow. again ymmv

I remember Haikelite did a charger cap that went on a battery tube of 4 cells. It acted as a charger, power bank and mini flashlight. I never got any details on how it worked, though.

FWIW, there’s a cool white version coming:

If I recall correctly, this might be of particular interest to JasonWW. :slight_smile:

Yep… you “recall correctly” TK, JasonWW will be beside himself. :smiley:

cool eh?? the world needs more warmer tints, how about making it a 4000k or even 3000k edition ??

Yeah. How about they make an LH351D 90CRI version instead?

Especially since we know they are going to be using them in the Lantern project.

Not really. It’s the stupid HI version instead of the HD. :rage:

Oh well, I’ll wait and see. Maybe they will do a HD vesion as well. I need to read that new thread.

FWIW, the HI version should give a more consistent tint without the usual Cree rainbow. And if you want it less throwy, DC-Fix is cheap. Together, they should make for a very nice-looking beam.

Offtopic, you have some nice nails :heart_eyes:

Back on topic, what light is this? For some reason, I thought you managed to put a triple reflector inside of a BLF Q8.