I completely agree with you. There will be compromise on both ends.
So now that the more affordable, compact, peak lumen D4 and D4S are available, it would be a great complement if Hank released a slightly longer, more expensive, regulated efficient version with the same emitter options. The driver on a buck boost is indeed larger and more complex, but Hank was able to make the smallest pop can light in the M43 that is still relevant today, so I have no doubt that he can reproduce his magic on a single cell version.
I think thats one of the things that makes Emisar’s so successful, its the fact that you have so many great emitter choices. As far as I am aware, there are no options like that for an efficient regulated light via buck/boost with the exception of the Noctigon Meteor M43 and quite possibly the Zebralights (not quite as customizable as the Emisar in emitter options).
If people are owning multiple Emisars of the same model in different colors and emitter options, I think these same people will also buy a regulated buck/boost version.
The opportunity for Hank is there and I think the demand is as well
While HWang is taking djozz’s suggestion regarding regulated D4 permutations into consideration, Nichia E21a/Optisolis versions, perhaps even mules could be offered.
A current regulated aspheric D4 with 4+ emitters of the category, and 18350 tube would be tempting.
I’m hoping that a single emitter D4 (D1/4th?) will be created. I love my D4 with Nichias but it doesn’t get as much pocket time as I thought it would because of the extreme power and the possibility of accidentally turning on. I keep it in a Convoy holster but that keeps it from being an EDC light.
Less power, but still small and having a great UI would be a welcome addition. Maybe with an XHP35 HD or HI?
I also hope that they try to revive their 7 emitter design, but not with a trio of 18650s like they had planned, but with the capability of using a high drain 21700 like the 30T.
Linear FET drivers like that exist. For example, led4power makes some. They’re typically more efficient than a PWM FET driver, and slightly more efficient than a FET+N+1 driver… but less efficient than a boost or buck at most levels. Because instead of burning off extra voltage as heat, a buck driver converts the extra voltage into usable power.
At direct drive the FET isn’t burning off any voltage, you really can’t get any more efficient then that (at the same current level) with a buck boost because now you have an inductor in series with the LED in addition to a FET, (unless you have a bypass FET). I would like a buck boost, but peak power is kind of the selling point of an Emisar D4. My use case doesn’t require longer run time and I’ll take my zebra if I do require it. I’m not going to say that its worthless to develop a buck boost D4, and I would probably buy one, but I wonder what I would have to give up in size, brightness, etc.
Yes, but at virtually every other output level, a buck/boost tends to be more efficient. And there’s no reason a buck driver couldn’t also have a FET for turbo. It could use whichever power channel is most appropriate for each level. The main drawback would be an inability to ramp smoothly all the way to turbo. Instead, it would have a gap in the ramp when it switches from the top of the buck circuit to the FET.
While trying to reassemble my D4 (after flashing Anduril) one of the e-switch solder pads got ripped off the driver . Is this repairable or do I need a new driver?
Looking at the photo of the driver in the 1st post of this thread, It sure looks like the switch goes to pin 2 on the MCU. You might be able to see the trace between the pad and the switch pin.
I can confirm the pad labeled SW+ is connected to pin 2 of the ATTiny85. The other goes to ground, which pin 4 is a convenient point to connect to ground. Or the adjacent pad of the closest resistor R?.