KC1 keychain light is available now

But you see, that’s each emitter at about 1A. They’re going to be more efficient at 7.5A/16 emitters ~ 0.57A per emitter.

From TA’s test, four emitters at 2A (0.5A per emitter) produced 753 lumens. That’s 188 lumens per emitter, which gives us 3008 lumens for 16 emitters.
Same test, 3.5A to four emitters, gives us 1205 lumens. If we maintained that power per emitter ratio (.875A), we’d get 8 or 9 emitters, and probably around 2600 lumens.

Fair enough.

https://docs.google.com/spreadsheets/d/1CERSuF2JvYtjsoyPh-wEZ0dG6fSI-FDCjcTEVMSppiw/edit#gid=0

Maukka test, lets call it E21A 4500K - 163lm (@ 0.5A) * 16 = 2,608 lm

Actual draw is 0.47A so even less (–5), then subtract for lens (–2) and light lost to side of bezel (–5%), less still. Conservative <2300lm

Point remains.

I don’t have one so I don’t know what the highest safe setting is… but E21A does not use a direct thermal path because the LEDs don’t support it. So it’s generally more sensitive to heat than other LEDs. This is why the power is limited to 5A or less on that model.

At a guess, it’s probably okay… but personally I would keep it set to a lower limit.

Conversely, lights which are too dangerous to gift to regular folks… probably shouldn’t have USB charging built in. It might make them seem gift-able.

Thanks for the reply! I know it is personal preference, but I would be very interested to know what limit you would prefer to set for D4V2 Ti with:

  1. E21A (5A driver)
  2. Nichia 219b (modded to, from 219c, normal, old driver)
  3. XP-L HI (normal, old driver)

Also, some interesting observations:

  1. The secondaried and switch LEDs seem quite a bit less bright on low, which is very good, for nightstand duty
  2. When setting the floor to 1/150 the light will come on every time without a problem, but with a delay. I do not mind that. The problem is that if I go to Turbo from there by double click and then double click to go back from turbo to floor of 1/150, the LEDs go off, while the light still think it is on. A floor of 2/150 acts the same. 3/150 works fine. Toykeeper, is it possible to correct the turbo --> 1/150 issue (LEDs going off) via firmware? If so, I do not mind the delay on the initial turn on, as I like the low moonlight mode quite a lot.

Not really. It’s a side effect of how the regulator chip works. Technically, 1/150 and 2/150 shouldn’t produce any light at all, because they have the regulator chip set to a level of zero. But it usually allows a small amount of power to pass through even at “zero”, so it’s included as an option because it can provide a nice moon mode.

However, when coming down from a high level to “zero”, it generally overshoots the usual brightness and hits the actual floor… and then slowly settles back to where it should be. There isn’t really a way to fix this in firmware, that I’m aware of. When it doesn’t turn on at a zero level, the chip is operating correctly. If anything in this setup is a bug, it’s that the moon level works at all… because technically, it shouldn’t.

To truly fix it, the driver would need another power channel for the low modes. Like, if the main chip runs at 5 A, the low-mode chip could be like… 80 mA, or about 1/64th as much power. I’m hoping there will be a driver like this eventually, because it would make better low modes, and it would greatly increase the resolution available for brightness.

But that doesn’t exist yet. For now, it’s limited to about 2 lm per step.

That makes sense. The about 2lm low mode of 3/150 is not bad, but the 1/150 is so much better that I am torn and just switched back to it, despite the turbo —> 1/150 issue. I am sure I will move back and forth between them for a while, until I settle.

A way this could be fixed in firmware, I think, is when the floor is set at 1/150 or 2/150 and turbo has been activated from that level, when double clicking from turbo to go back, that could be done in two steps. Step one: turbo —> 3/150, step two: 3/150 to 1/150 (or 2/150). That would solve the problem of turbo to floor.

I cannot think of a way to solve the issue of slow turn on, and it is a bit strange having to let go of the button before the light goes on, for the light to go on at 1/150 and not start ramping before I even see any light, but that is not a huge issue. Unless there is another special check in the firmware and when the light turns on at 1/150, the start of ramping is purposefully delayed.

I think those two checks in the firmware, if they are possible and you can be bothered to implement them, would solve the 1/150 and 2/150 issues and make the modes quite usable.

Any suggestions regarding temperature settings, as asked above?

Does anyone else’s KR4 exhibit flickering at the default low (3/150) setting? It’s not as pronounced as the flickering that happens at 1/150 and 2/150 (though I understand those are officially below spec) but it is still noticeable, especially when the light is stationary for ceiling bounce, etc.

Edit: Flicker is visible from 1/150-6/150

I’ve noticed that, too. I figured it was just a quirk of this driver, though it is a little frustrating. I rarely leave my lights stationary, so I can kind of pretend it isn’t there. I would be interested in TK’s or Hank’s thoughts on this, though.

Sorry, I don’t have anything helpful to add. I only have a late prototype, and it doesn’t flicker at 3/150.

At 1/150 and 2/150 it’s expected to flicker a bit, but at 3/150 or above I haven’t seen it happen. It might be worth cleaning the contacts though, since dirty connections can cause flickering on almost any light.

I have three - no flicker

I’ll try that, thank you for the suggestion.

It may be worth mentioning that mine is the E21A version; not sure if different emitters can effect how the driver behaves.

Do you know what bins are tested in that spreadsheet, there is no mention, all of the CCTs come in 3 luminous flux bins, for example D180, D200, D220.

You can easily use Nichia datasheets basically, at least that is what I have done, and could easily figure out it cannot be anywhere over 2500lm using D220 (220lm-240lm) bin.
Usually datasheets are ignored even if they can prove very useful, especially for the E21 they are pretty good.

The rating is for 700mA . Then you can see what multiplier to use for that 700mA with the graph blow.
Multiple that 220lm by 0.65x and get a relative 143lm * 16pcs = 2288lm
Or the max rage of 240lm by 0.65x and get 156lm *16pcs = 2496lm

D220 for that one. It’s from the ones on virence.com most are 200,220,240

So D220 for the 4500K?
That is why I was calculating with D220 ( min 220lm and max 240lm at 700mA) for a 4500K.

5000K is D240 at IOS, so with that the results are 9% higher (increase from min 220lm to min 240lm at 700mA) for the minimum and 8.33% higher for the maximum (increase from max 240lm to max 260lm at 700mA)

It sounds to me like 1x7135 + 5A CC (+ FET?) driver might be a means to achieve this.

I don’t think Loneoceans’ lume1 inductor would fit in the shallow driver cavity of the D4, nor do I know how low that driver can go, but the buck-boost + FET approach seems appealing, too.

A 7135 chip does 350 mA. To make this work well, it would probably need to be significantly smaller… and ideally a nice power-of-two ratio to the higher power channel, like 5A * 1/64 = 78.125 mA.

What we have now:

  • 5A = ~2000 lm
  • 2000 lm / 256 = 7.8 lm resolution with 8-bit PWM
  • 2000 lm / 1024 = 1.95 lm resolution with 10-bit PWM

It uses 10-bit PWM, or 1.95 lm per step. But 1.95 lm is pretty coarse resolution at the bottom end of the ramp… so the idea is to add a second power channel to fix that. It’d make better moon levels, and make the bottom of the ramp smoother instead of having visible steps.

If the second channel used a 7135 chip, it would effectively be an upgrade from 10 bits to ~11.5 bits. It’s not nothing, but it’s not a big upgrade. The effective resolution ends up at about 0.6 lm per step. And the math gets really awkward since it’s not very close to a power of two ratio between the power channels.

So I’m hoping for something smaller with a cleaner ratio.

If the second channel has a power-of-two ratio to the main channel, we can treat it like it’s just extra resolution on the main channel. Like, let’s say we run the main channel in 8-bit mode. It then has 256 steps, and each step is 7.8 lm. Then add a second channel with a 1/64th ratio. Now instead of 8 bits, we basically have 14 bits… and each step is 0.12 lm.

Or it could even go as far as 16 bits… 5A for the main channel and 20mA for the lower channel. This gives 16-bit resolution where each step is 0.03 lm. And it would still run at 16 kHz so there wouldn’t be any visible PWM.

Basically, if 7135 chips or other linear regulators come in a 20mA variety, that would probably be about right.

Output tested using Texas Ace Lumen Tube calibrated with Maukka lights at 2 seconds. Light quality measured using Sekonic C-800-U. The E21A 4500K is just as rosy as the 219B sw45K but with cooler tint. It is a very beautiful tint but I think mixing it with 8x4500K with 8x3500K will result in somewhere near 4300K, which would be more idea. Also the E21A 4500k does not reach 9080.

The E21A 2200K is much rosier than I expected. The 2200K batch that Clemence had was on the BBL. This batch is nicer IMO and exceeded my expectations. Because of the negative duv, it doesn't take long for your eyes to adapt because it doesn't look very yellow. The 2200K tint is similar to a pinkish sunset whereas the E21A 2000K that Clemence sells look like real candle light.

Also pay attention to how much output the bezel kills on the mule lights. Even the color of the bezel (stainless steel vs dark gray) makes a big difference in output. I think Hank should use white mcpcb for the mules to reflect as much light as possible to minimize output loss.

The D4v2 TI with the 16x E21A 2200K is the only light with a loud electronic whining noise on turbo and it smokes as if there's a fire burning. At first I thought it might be moisture that its burning but the smoke doesn't stop and it sure doesn't smell like water. I wonder what is the cause. I don't get this on the KR4 16x E21A 4500K mule or any of the other Hank lights. Anyone have this experience?

D4v2TI 16x E21A Mule Warm White Switch (Aux Light) 0 lumens 2370K 0.0079 DUV 68.4 CRI Blue light relative amplitude 0.19 -12.2 R9 20.5 R12 72 Rf 90 Rg Molicel P26A
D4v2TI 16x E21A 2200K Mule 5A Regulated w/ DD Turbo no bezel Turbo 3,612 lumens 2370K -0.0054 DUV 89.6 CRI Blue light relative amplitude 0.24 49.3 R9 92.4 R12 87 Rf 102 Rg Molicel P26A
D4v2TI 16x E21A 2200K Mule 5A Regulated w/ DD Turbo Turbo 2,991 lumens 2319K -0.0050 DUV 89.8 CRI Blue light relative amplitude 0.23 49.3 R9 93.0 R12 87 Rf 103 Rg Molicel P26A
D4v2TI 16x E21A 2200K Mule 5A Regulated w/ DD Turbo Top of Ramp 1,200 lumens 2234K -0.0034 DUV 92.2 CRI Blue light relative amplitude 0.20 59.3 R9 92.7 R12 90 Rf 103 Rg Molicel P26A
D4v2TI 16x E21A 2200K Mule 5A Regulated w/ DD Turbo lowest mode 4 lumens 2148K -0.0026 DUV 92.6 CRI Blue light relative amplitude 0.17 62.2 R9 88.8 R12 91 Rf 101 Rg Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo No Bezel Turbo 4,733 lumens 5218K -0.0137 DUV 91.5 CRI Blue light relative amplitude 1.00 69.9 R9 84.0 R12 90 Rf 106 Rg Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo SS Bezel Turbo 3,879 lumens 5075K -0.0125 DUV 92.2 CRI Blue light relative amplitude 1.00 73.6 R9 84.4 R12 90 Rf 106 Rg Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo Gray Bezel Turbo 3,578 lumens 5120K -0.0126 DUV 92.2 CRI Blue light relative amplitude 1.00 73.8 R9 84.3 R12 90 Rf 106 Rg Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo SS Bezel Top of Ramp 1,578 lumens 4922K -0.0086 DUV 94.4 CRI Blue light relative amplitude 1.00 75.0 R9 77.3 R12 91 Rf 105 Rg Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo Gray Bezel Top of Ramp 1,477 lumens Molicel P26A
KR4 16x E21A 4500K Mule 7.5A Regulated w/ DD Turbo SS Bezel lowest mode 5 lumens 4692K -0.0055 DUV 94.7 CRI Blue light relative amplitude 1.00 73.3 R9 74.2 R12 91 Rf 102 Rg Molicel P26A
KR4 4x XP-L HI 4000K 5D Turbo 3,388 lumens 4381K -0.0049 DUV 72.8 CRI Blue light relative amplitude 1.00 -12.7 R9 47.3 R12 67 Rf 99 Rg Molicel P26A
KR4 4x XP-L HI 4000K 5D Top of Ramp 1,621 lumens 4313K -0.0039 DUV 72.5 CRI Blue light relative amplitude 1.00 -14.6 R9 46.7 R12 67 Rf 99 Rg Molicel P26A
KR4 4x XP-L HI 4000K 5D lowest mode 7 lumens 4047K 0.0007 DUV 73.7 CRI Blue light relative amplitude 1.00 -15.9 R9 44.9 R12 71 Rf 98 Rg Molicel P26A
KR4 4x E21A 3500K Turbo 1,135 lumens 3903K -0.0070 DUV 96.6 CRI Blue light relative amplitude 0.89 92.0 R9 85.0 R12 94 Rf 103 Rg Molicel P26A
KR4 4x E21A 3500K Top of Ramp 978 lumens 3748K -0.0054 DUV 96.6 CRI Blue light relative amplitude 0.82 92.5 R9 86.3 R12 94 Rf 104 Rg Molicel P26A
KR4 4x E21A 3500K lowest mode 7 lumens 3637K -0.0010 DUV 95.8 CRI Blue light relative amplitude 0.75 82.3 R9 81.9 R12 93 Rf 101 Rg Molicel P26A
D4v2 SST-20 Red LED Turbo 1,175 lumens Molicel P26A
D4v2 SST-20 Red LED Top of Ramp 545 lumens Molicel P26A
KR1 W2 Turbo 1,174 lumens 8831K -0.0141 DUV 68.7 CRI Blue light relative amplitude 1.00 10.7 R9 42.1 R12 56 Rf 100 Rg Molicel P26A
KR1 W2 Top of Ramp 975 lumens 8118K -0.0113 DUV 67.3 CRI Blue light relative amplitude 1.00 -0.1 R9 40.6 R12 56 Rf 99 Rg Molicel P26A
KR1 W2 lowest mode 10 lumens 6040K -0.0020 DUV 67.8 CRI Blue light relative amplitude 1.00 -21.7 R9 37.1 R12 61 Rf 97 Rg Molicel P26A
D4v2 SST-20 2x4000K + 2x2700K Turbo 1,940 lumens 3107K -0.0050 DUV 96.6 CRI Blue light relative amplitude 0.44 81.7 R9 91.8 R12 94 Rf 102 Rg Molicel P26A
D4v2 SST-20 2x4000K + 2x2700K Top of Ramp 1,108 lumens 3306K -0.0017 DUV 97.1 CRI Blue light relative amplitude 0.57 91.1 R9 87.9 R12 94 Rf 103 Rg Molicel P26A
D4v2 SST-20 2x4000K + 2x2700K lowest mode 3 lumens 3486K -0.0015 DUV 97.0 CRI Blue light relative amplitude 0.72 95.4 R9 80.1 R12 91 Rf 99 Rg Molicel P26A

(disclaimer: I do not know electronics well so I could be wrong)
A very simple 20mA channel could be no more than a resistor inline with battery and led, switched by a tiny FET. The current (and so the light output levels) would not be truly constant but vary somewhat with battery voltage but maybe that is not such a big deal.

Thanks for all these measurements. The output loss due to the bezel is significant, I did find it weird that the LEDs were packed to the edge of the MCPCB , I think they should be centered with the wires and screws on the edge instead.

The color measurements are not integrated but at the center of the beam right ? E21As do have quite a bit of tint and CCT shift so that explains the low duv and higher CCT.