Introducing the MELD-X RGBW(uv) flashlight driver!

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tterev3
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Introducing the MELD-X RGBW(uv) flashlight driver!

Update 10/15/2017: I am discontinuing this driver offering due to lack of interest and will no longer keep boards in stock. Feel free to contact me if you have an RGBW application you’d like to discuss. Information below is preserved for posterity but no longer considered current.

Quote:

UPDATED 1/4/2017: added user-configurable PWM speed and dual switch support
UPDATED 5/4/2017: updated list of hosts. added 7135 warning. changed firmware notes for clicky

Introducing the MELD-X RGBW flashlight driver!

What is it
MELD-X is a driver for multicolor LED flashlights. It is a basic linear regulated driver using AMC7135 regulators. It has 5 output channels (White, Red, Green, Blue, and Ultraviolet); the UV channel can be disabled in the menu for installations with only RGBW. It comes in several sizes, and can be programmed for either momentary switches (also called “e-switch”), or clicky switches (reverse clicky preferred). The momentary switch version is generally preferable as it has a much more complete user interface and more complete function set.

Specifications

  • Runs on single-cell rechargeable lithium batteries only.
  • Linear regulation on all channels with PWM.
  • Sizes: 16mm, 18mm, 24mm. 16mm is double stacked and can be trimmed to 15mm. 18mm and 24mm can both be trimmed to 17mm.
  • White channel: 15.6kHz PWM at 11-bit dimming (2048:1) or 1.9kHz PWM with 12-bit dimming (4096:1), user configurable. 1.4A (16mm board) or 1.75A (all other sizes). Dims on a 256-step logarithmic ramp.
  • Red channel: 3.8kHz/7.6kHz PWM at 350mA. 9-bit dimming (512:1 ratio)
  • Green & Blue channels: 1.9kHz/7.6kHz PWM at 350mA. 8-bit dimming (256:1 ratio)
  • UV channel: 350mA (16mm board) or 700mA (all other sizes) (no PWM)
  • Standby current (momentary switch version) 20uA
  • Operating current (non-LED current consumption) 1mA (low speed PWM) or 2.9mA (high speed PWM)
  • Input voltage range: 4.2V maximum. Minimum varies based on LED Vf – typically 3.4V to maintain regulation for all channels. Processor will operate down to 2.0V.
  • A quick feature list: ramping, mode memory, smart momentary, dual switch support, battery voltage measurement, continuously adjustable strobe, RGB mixing, inactivity timer, locator beacon, burst dimming, dim to red, user-adjustable primary level, lockout, tactical mode

Background
I’ve been working on my series of MELD (Multicolor EDC Light Driver) drivers for several years now. I started with the goal to build a flashlight that included every feature one might ever want in a flashlight, all in a single device. Although I produced several hardware versions that worked well, I had been held back all along by holding myself to specifications that were a bit too strict. I’ve recently decided that it would be much better to do everything I can to get functional RGBW lights out there to everyone, rather than work endlessly towards an unreachable set of goals. So I put a big X through my long-standing requirement to run on primary cells and made the MELD-X driver, with the goal of making an excellent multicolor flashlight accessible to everyone. The firmware on MELD-X also comes with a significant upgrade over the original MELD drivers: 12-bit dimming on the white channel. The range and smoothness of 12-bit dimming as compared to the typical 8-bit is a huge improvement to the user experience (in my humble opinion; I was amazed the first time I tried it, it made a much bigger difference than I expected)!

The user interface
For momentary switch (standard MELD), watch this UI video: https://www.youtube.com/watch?v=B09tLW9JaXI
And this configuration menu video: https://www.youtube.com/watch?v=ExLRj6Zoccg
The standard UI is also written up in this document: https://drive.google.com/open?id=0B8AQ5y6R0lboQW1Rb0J4M1JmN1U
The clicky UI is written up in this document: https://drive.google.com/open?id=0B8AQ5y6R0lboQ3lwbXBPc2FvdlE
For clicky switch versions, here is an informal demo video: https://www.youtube.com/watch?v=H24tjSe3LcQ
If you have suggestions about changes or updates to the UI, let me know! I am always improving it and I want to get as much input as possible.

What you get
I will offer the drivers in multiple sizes, and they will be pre-programmed with either the clicky or the momentary switch firmware versions (you must specify when ordering). In order to make this as accessible as possible to everyone, I will offer a bare-bones version for as cheap as I can, which will consist of a PCB with microcontroller and capacitor ONLY, and it will be up to the user to source and install the AMC7135s. This version will be flat enough to ship in a regular envelope to keep cost down, but it will therefore be at your own risk for shipping damage or loss as there will be little physical protection and no tracking or insurance. Bare-bones boards look like this:
16mm: http://i417.photobucket.com/albums/pp254/tterev3/20161227_102444.jpg
18mm: http://i417.photobucket.com/albums/pp254/tterev3/20161227_102457.jpg
24mm: http://i417.photobucket.com/albums/pp254/tterev3/20161227_102505.jpg
WARNING: recently some AMC7135 regulators have been appearing on the market made by a different manufacturer. These have a much slower turn-on time and therefore don’t work at very low PWM levels – if they are installed on a bare-bones MELD-X board, the lowest levels may not work. I recommend only using the “Raptor Claw” version discussed in this thread.
The next step up will be a fully assembled board ready to use, shipped by USPS Priority for $6. All boards will ship with ultraviolet disabled by default – if you install UV in your light, you will have to use the configuration menu to activate it.

How to get it
To order one, please send me a PM. In your message, please include all of your choices for the options below. Payment is through Paypal only – I will confirm the total and then tell you my Paypal address. Here are the options:
1. Size: 24mm, 18mm, or 16mm
2. Firmware: Standard (momentary) or clicky
3. Build: Bare-bones or complete
4. Shipping: envelope or Priority flat-rate
I don’t have a clear idea on what the demand might be like, so I haven’t stocked up very many. When you order I will let you know what the lead time will be like. It will be 2-3 days to ship if I have it, or 2-3 weeks if I have to order the PCB.

Cost
The only things that affect the price is the build option and the shipping; board sizes and firmware options make no difference.
Bare-bones board: $10
Complete board: $20
Envelope shipping (bare-bones only): $1
Priority shipping: $6
Pricing example: three bare-bones 18mm boards shipped by envelope would total 3*10+1=$31

How to install it
Installing RGBW in a flashlight is not an easy modification job. That said, I’ve designed the driver to make it as easy as possible. There should be a driver option that will fit most common host lights, although some may require trimming to fit perfectly. All four or five of the LED positive connections should connect to the hole marked “+” on the driver, and each LED’s negative connection should connect to the labeled hole on the driver (exact labels read “RED,” “GRN,” “BLU,” “uv,” and “W”). For momentary switch versions, connect the switch between the hole labeled “-” and the hole labeled “S.” Here is a connection guide: https://drive.google.com/open?id=0B8AQ5y6R0lboRTlUaVlhamtBNmc
For dual switch installations, the “S” connection goes to the down switch, and the smaller hole labeled “m” (label on bottom) goes to the up switch.
Here is an installation video I’ve created for clicky versions:
https://youtu.be/NH_LdMqRw2g
And a few additional notes about assembling the 16mm version are in this video: https://youtu.be/zeA_W0_zteA
For momentary switch versions, there will always be some hacking needed to get the switch hooked up. In most lights there is a small daughter board holding the switch that will need to be glued or otherwise held in place to make it work. Every light is different, so this part is up to the user.

What LEDs?
MELD-X can be used with any standard (single-die) LEDs in white, red, green, blue, and (optionally) ultraviolet. The simplest setup is to use an XM-L color on a star board. For a better white beam, you can use separate LEDs and keep the white emitter centered in the optics. The easiest way to do that is to get one of my LED boards from OSHPark:
XQ: https://oshpark.com/shared_projects/vJaq2G1L
XB: https://oshpark.com/shared_projects/4tMsLxi9
XP: https://oshpark.com/shared_projects/JAd9pidN
XM: https://oshpark.com/shared_projects/bqAKxEuw
For better thermal performance, these LED boards can be converted into hybrid metal-core boards by using a technique I demonstrate in a segment of this video: https://youtu.be/bg5njtFVszA?t=143
The color parts I recommend are Cree XQ-E HI (flat lens) parts.
For UV parts, I recommend the Lumileds LHUV series. They come in several wavelengths and will fit on the XQ footprint on my LED boards. Example: http://www.mouser.com/ProductDetail/Lumileds/LHUV-0400-0500/?qs=sGAEpiMZ...

What host light?
There are very few single-cell lights that MELD-X won’t work with. For the best performance, choose a host with a momentary switch and with a textured reflector with an aperture at least 7.3mm wide (to fit an XP LED board linked above). My favorite host is the Olight S10, but it is one of the more challenging options due to the small size.
MELD drivers in some form have been used successfully in the following hosts:
Nitecore EC11, Olight S10, Ra Clicky, Novatac 120P, Fenix TK16, Fenix PD12, Fenix HL50, Skyray King, Blackshadow Queen, Nitecore EX11, Sunwayman C10R, Solarstorm SC02, Trustfire Z1, Romisen RC-C6, MX Power ML-310, Ultrafire 0517, Skilhunt DS10, Fenix E35UE, Solarstorm SC01, Olight S1… if you try a new host, send it to me to add to the list!

What else you’ll need
Thin wire – I recommend 30AWG or 29AWG Kynar-insulated solid-core hookup wire.
Something for the positive contact (not strictly necessary on the 16mm version). Can be a small spring, big lump of solder, chunk of thick copper wire, etc.

Product support
MELD-X drivers will go through visual inspection before shipping, but they will not be tested. If there is a defect with a driver I will replace it for free.
Please be aware that this is not an easy installation job, and things may go wrong. I will do my best to provide remote support by email, but I won’t be able to solve every issue, and I can’t physically debug your malfunctioning flashlight.
The firmware is always going through tweaks and improvements. I will upgrade your flashlight to the latest firmware for free, forever. You must pay for shipping both ways, and must not have installed the board in a way that prevents programming (back of board must be accessible inside the battery compartment, programming vias must not be filled in, electrical modifications must not interfere with programming signals).
In general, I cannot support requests to modify the firmware to suit your preferences. You are welcome to contact me if you would like to work with me on a custom firmware project, it will just be separate from my basic MELD-X driver offerings.

Modifications and other uses

  • Any LED can be used instead of UV. Since the UV functions in the UI are fairly separated (no mixing or use in special modes), it can easily be switched to something else – infrared, warm white, a laser, an emitter with a different beam pattern, etc.
  • Since MELD memorizes its operating mode at all times, the momentary-switch version can be used in lights that have both a momentary switch and a power switch.
  • If you want a higher output current on the white channel, you can remove those regulators and break out the PWM signal to an external driver, a bunch more AMC7135s, or FET (for direct drive).
  • The clicky versions will come with a resistor stacked on the capacitor to set the reset time for the UI. I prefer a very short reset time (less than 1 second) to allow fast cycling through the modes, so that is how the boards will ship. You can remove and replace this resistor to adjust the timing to your preference. They ship with 43kΩ for a ~0.75s reset; a 150kΩ has been tested for ~3s reset time.
  • The momentary switch version includes a menu option to disable colors, so if you really like the basic parts of the UI and want to make a white only or a white+UV flashlight with the MELD interface, you can do that with the existing hardware and firmware.
  • The momentary switch signal can be used with things other than a normal switch – just pull it low to activate. MELD has been successfully used with alternative switch setups, such as piston-drive lights, capacitive sense switches, and with magnetic rings and hall-effect sensors.

Wow you read through all that? Thank you! If you have questions or comments, ask them right here – someone else probably has the same question!

Edited by: tterev3 on 10/15/2017 - 15:57
LightRider
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Pm sent:)

emarkd
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pm sent. Thanks for offering these!

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Looks awesome. I particularly like how it has programming vias exposed for reflashing without disassembly. Smile

Is there any chance you could speed up the white PWM by a factor of about 10 or 20?

tterev3
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ToyKeeper wrote:
Is there any chance you could speed up the white PWM by a factor of about 10 or 20?

Not by that much. If I drop to 12bit resolution and bump up the processor clock I could get to 8kHz, but it comes with significant tradeoffs. The chip will consume more power, and I think you’d give up a lot on the bottom end of the dimming range from turn-on delay. At that speed, the lowest output is only a 31 nanosecond pulse, which I doubt will even turn on the amc7135. They don’t spec a turn-on time, so I’ll run an experiment.

tterev3
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Ok I wrote some experimental firmware to run the PWM at 7.8kHz. Running the processor this fast bumps the current consumption from 1.0mA up to 2.9mA (non-LED current) while it’s active. To get this speed the PWM resolution is also dropped to 12-bit (4096:1).

It appears the AMC7135 doesn’t start to turn on until somewhere around 120-150 nanoseconds, doesn’t reach the 350mA setpoint until around 1 microsecond, and doesn’t stabilize its output until 6 microseconds.

At 7.8kHz PWM, you give up about 6 steps at the bottom before it will even turn on, and 30-something steps before it behaves linearly and predictably. For comparison, the 976Hz PWM at 13-bit resolution has turned the LED on reliably at 1 count so you get to use all 8191 steps.



What do you think? Is it worth the tradeoff? Ramping still looks pretty good to me. I can’t really perceive the 976Hz so I didn’t see any benefit to going higher; is 1kHz visible to you?

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There was a bit of a kerfuffle here recently because the Reylight Pinepple wound up shipping with 2kHz pwm and some folks were unhappy about that. You’re being upfront and open so I can’t see there being an issue here, but I can guarantee theres a contingent of blfers who won’t touch this driver because they say the low pwm bothers them.

Fwiw, I can’t usually see pwm either. I couldn’t see it at 2khz in the Pineapple. I’ll be glad to report back on your driver when I’ve figured out how to use it. Smile

And by the way, Rey reworked his driver to 9kHz for the next run of lights. Folks seemed to appreciate that.

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Isn’t it more the whining with low pwm frequency in some lights which bothers people? As far as I know a even higher frequency is required to avoid this noise.

tterev3
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Flashy Mike wrote:
Isn’t it more the whining with low pwm frequency in some lights which bothers people? As far as I know a even higher frequency is required to avoid this noise.

Usually that’s only an issue in lights with buck or boost regulators, since it’s the inductors that cause audible noise
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tterev3 wrote:
Ok I wrote some experimental firmware to run the PWM at 7.8kHz. Running the processor this fast bumps the current consumption from 1.0mA up to 2.9mA (non-LED current) while it’s active. To get this speed the PWM resolution is also dropped to 12-bit (4096:1).

It appears the AMC7135 doesn’t start to turn on until somewhere around 120-150 nanoseconds, doesn’t reach the 350mA setpoint until around 1 microsecond, and doesn’t stabilize its output until 6 microseconds.


Yeah, the 7135 chips don’t activate as quickly as a FET. The bottom few PWM levels tend to be “off”. Running right at the edge like that, minimum pulse width, also makes the output more voltage-sensitive. I normally drop the speed to like 8 kHz for moon mode to improve stability, unless I can get some particularly good 7135 chips. Usually the 350mA ones activate faster than the 380mA ones, but it still varies a lot per brand and per emitter type and such.

The 2.9mA MCU current is within the range the attiny uses when it has several features turned on, though I can also get moon mode (including the LED) down to like 1.4mA if I turn off some MCU functions. And you’re using something much more capable than an attiny, so … not bad. Smile

tterev3 wrote:
What do you think? Is it worth the tradeoff? Ramping still looks pretty good to me. I can’t really perceive the 976Hz so I didn’t see any benefit to going higher; is 1kHz visible to you?

Yes, 1 kHz is easily visible to me. I generally notice anything below ~8 kHz during normal use, and 1 kHz is slow enough to be pretty distracting.

I have about a hundred lights. If I were to list them in order of PWM speed, the bottom of the list looks something like this:

    96. Reylight Pineapple, ~2000 Hz
    97. CNQG Brass AA, ~990 Hz
    98. MELD 2.9, 488 Hz
    99. Blackshadow Terminator, 188 Hz
    100. Generic UltraFire SK-68, ~130 Hz

Most of the items at the bottom of that list are there only because I haven’t gotten around to fixing them yet, giving them new drivers.

Unfortunately for my MELD light, the PWM speed made the difference between EDC and shelf queen, because all the white modes are so strobey. Here’s MELD 2.9 running at 488 Hz, showing approximately how it looks to my eyes during use: (photo not edited)

… and this is the same test on a $3 nanjg driver at 4.5 kHz:

Some are happy with that speed (4.5 kHz), others still think it’s too slow. I generally aim for the slowest speed which people won’t complain about, which is about 10 kHz for visual purposes… but that often makes an audible whine, so closer to 20 kHz to get rid of sounds in the human hearing range too.

I’d probably be happy with 8 kHz, though it’s still a bit slower than my usual EDCs. The usual is something like this, with the bistro firmware option. I’d be happy to send you one if you’re curious.

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I have friends that see it, they don’t know what it is, they are just annoyed by it. I mean some might not even know why they
like another light more than the other, they cannot actually talk about PWM and frequencies, that is not really in their
vocabulary.

For some time there were many displays with seriously low PWM and people started claiming a certain monitor makes their head ache
after a couple of hours, after switching to another display model, their headache was gone. Nowadays most display reviews
measure to see the frequencies so automatically a high frequency like 19Khz is labeled as flicker free, etc.
No respectable monitor review website will ignore or not measure the frequency.

I had 7135 drivers with audible noise, those from KD they all where noisy back in the day, their frequency was around 14Khz
But then not all ears hear the same, I know people that hear worse than me, others better.

I can tell that at some point I also have a forgiving attitude towards low frequency PWM, like with my laptop, I keep seeing it
but I keep saying I cannot buy another laptop, so there’s that reasoning.
When I am half asleep and there is a car chase in a night scene, well at that moment I simply cannot force my set notions of the laptop’s PWM,
is all feelings, meaning annoying.

Mercedes, not a cheap brand, I see certain models taking a corner leaving a trail of LEDs behind them, really obvious PWM,
that is so distracting in traffic and quite frankly Mercedes makes a pretty bad impression on me for that reason, I am
surprised this is not regulated.
Again not all people are the same, some hear better, some see better, some worse, etc. So the decision of using low PWM
should not be made base on the “blind and deaf” (of course, it’s a hyperbole)

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For me the 4kHz of the nanjg driver is unnoticable if I don’t look for it, between 4 and 1 kHz is noticable but not annoying, and everything under 1kHz is annoying.

I see low PWM everywhere nowadays, cars, lighting in busses, even street lamps. With flashlights I can change the driver or use another flashlight, but those street lamps may take 20 years before they are replaced.

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Ok, I’m on it. I’ll add a user-configurable option in the menu to switch between high and low PWM speeds. I’ll probably do a 1.9kHz low at 12-bit resolution and a 15.6kHz high at 11-bit resolution. Color channels will run at 1.9kHz and 7.8kHz respectively.

The tradeoff will be that you get a higher minimum on the high-speed setting, as well as faster battery drain on very low levels (the minimum level would go from ~550 hours to ~200 hours of runtime on a decent 16340 cell).

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Would it be difficult to include a configurable high cri option. Where the user can set the levels of each color in the high cri config menu?

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Anyone have suggestions for a cheaper uv led in the xq footprint?

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LightRider wrote:
Would it be difficult to include a configurable high cri option. Where the user can set the levels of each color in the high cri config menu?

You can get high CRI by using a high-CRI white emitter. Adding narrow-band red/green/blue isn’t likely to improve the tint, even if you can get them to focus on the same spot.

The typical result of having R+G+B+W powered on at the same time is a white spot with three weird-shaped color splashes next to it.

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ToyKeeper wrote:
LightRider wrote:
Would it be difficult to include a configurable high cri option. Where the user can set the levels of each color in the high cri config menu?

You can get high CRI by using a high-CRI white emitter. Adding narrow-band red/green/blue isn’t likely to improve the tint, even if you can get them to focus on the same spot.

The typical result of having R+G+B+W powered on at the same time is a white spot with three weird-shaped color splashes next to it.

With D.C. Fix on the lens I can mix dr jones driver to a great tint. Far better than any single emitter tint. Really. With xml RGBW, op reflector, and dc fix the beam is nearly perfectly blended.

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LightRider wrote:
Anyone have suggestions for a cheaper uv led in the xq footprint?

UV is difficult to do well in such a small space. It’s a really nice extra to have, but it’s not going to look as nice as a dedicated UV light with a bandpass filter lens.

Mine has 385nm UV, which is nice, but the close proximity to other LEDs has an interesting effect. Some of the other LEDs fluoresce when the UV emitter is on, which results in a bunch of non-UV light coming out the front. The green in particular likes to respond to the UV emitter, probably because it gets refracted through the white emitter’s dome.

Here it is again with the other four on:

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ToyKeeper wrote:
LightRider wrote:
Anyone have suggestions for a cheaper uv led in the xq footprint?

UV is difficult to do well in such a small space. It’s a really nice extra to have, but it’s not going to look as nice as a dedicated UV light with a bandpass filter lens.

Mine has 385nm UV, which is nice, but the close proximity to other LEDs has an interesting effect. Some of the other LEDs fluoresce when the UV emitter is on, which results in a bunch of non-UV light coming out the front. The green in particular likes to respond to the UV emitter, probably because it gets refracted through the white emitter’s dome.

Here it is again with the other four on:

Interesting…

I’m looking for four xq uv led to use with an mtg2 on that noctigon with the xq pads. But this might see the same problem as you are describing? Think it will light up the mtg2 phosphor?

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I really would like a dedicated uv light but I’m afraid I won’t be satisfied with anything less that the 365 nichia that’s $30 a piece. Any cheaper options that might satisfy and work well in a dedicated uv light?

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LightRider wrote:
Any cheaper options that might satisfy and work well in a dedicated uv light?

I was pleasantly surprised at the array of new small uv parts I saw on mouser when I was writing this post. The LHUV parts came down to around $9 for several different wavelengths and there are a few new ones competing with those as well.

I’ve also been using some no-name eBay uv parts that are in fake xp-e packages that have been performing above expectations

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tterev3 wrote:
LightRider wrote:
Any cheaper options that might satisfy and work well in a dedicated uv light?

I was pleasantly surprised at the array of new small uv parts I saw on mouser when I was writing this post. The LHUV parts came down to around $9 for several different wavelengths and there are a few new ones competing with those as well.

I’ve also been using some no-name eBay uv parts that are in fake xp-e packages that have been performing above expectations

Do you have a link to the eBay listing you purchased from?

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LightRider wrote:
Would it be difficult to include a configurable high cri option. Where the user can set the levels of each color in the high cri config menu?

I’ll put some thought into it. I’m almost out of memory so I can’t add an interactive feature for setting up the different levels. What about picking a mixed color from the RGB mix mode (wouldn’t allow all three colors, but you’d get a configurable color added to the white)? Or maybe just an adjustable amount of added red – do blue and green matter for this function?

ToyKeeper wrote:
You can get high CRI by using a high-CRI white emitter. Adding narrow-band red/green/blue isn’t likely to improve the tint, even if you can get them to focus on the same spot.

I agree, but now I’m curious about this. When I get back to work next week I’m going to throw a MELD light in the sphere and see what impact it has on the CRI value.

tterev3
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ToyKeeper wrote:
Unfortunately for my MELD light, the PWM speed made the difference between EDC and shelf queen, because all the white modes are so strobey.

Argh, it pains me to know that your MELD S10 didn’t make the cut for EDC. The 488Hz PWM was too low for my liking as well, but unfortunately the SEPIC converter couldn’t handle being switched any faster. That was one of the biggest difficulties with trying to do primary and secondary cells – any switching converter that met the voltage and current requirements just wasn’t set up for good dimming. Hopefully MELD-X fixes all of that. The preliminary version of switchable PWM speed looks pretty good at 15.8kHz so far.

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tterev3 wrote:
When I get back to work next week I’m going to throw a MELD light in the sphere and see what impact it has on the CRI value.

I’d love to see how that turns out. I’ve done tint mixing before, and sometimes it can turn out very nice. My wide-spectrum BST produces more vivid color than any other light I’ve ever used. It’s four shades of white though, not white and three narrow-band colors. It’ll be fascinating to see the results.
tterev3
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LightRider wrote:
Do you have a link to the eBay listing you purchased from?

I think it was the 390nm version of this: http://r.ebay.com/O7nTU7

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tterev3 wrote:
Argh, it pains me to know that your MELD S10 didn’t make the cut for EDC.

It’s a fantastic light, and definitely a jewel to hold onto for a long long time. It has all the fun exotic modes, and is only missing the boring stuff I use for EDC purposes. So for daily use I tend to grab either one of the many lights I made or something small and boring (like a stock Olight S Mini or L3 L10-219). The majority of my use is on low (~10 lm) or moon (~0.3 lm).

The MELD light still gets EDC’d a lot though, and is covered in scratches to prove it. It’s small and fun, so why not keep it in my purse in case I need it? I just use something else for general-purpose illumination.

… and it sounds like the new MELD drivers add that last missing bit. It should be about as close as one can get to a light which does everything. Smile

LightRider
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tterev3 wrote:
LightRider wrote:
Would it be difficult to include a configurable high cri option. Where the user can set the levels of each color in the high cri config menu?

I’ll put some thought into it. I’m almost out of memory so I can’t add an interactive feature for setting up the different levels. What about picking a mixed color from the RGB mix mode (wouldn’t allow all three colors, but you’d get a configurable color added to the white)? Or maybe just an adjustable amount of added red – do blue and green matter for this function?

ToyKeeper wrote:
You can get high CRI by using a high-CRI white emitter. Adding narrow-band red/green/blue isn’t likely to improve the tint, even if you can get them to focus on the same spot.

I agree, but now I’m curious about this. When I get back to work next week I’m going to throw a MELD light in the sphere and see what impact it has on the CRI value.

Being able to chose a color to mix in with white would be a good compromise. It doesn’t take much when mixed with neutral white but a bit more for cool white. For me

Neutral white 100, red 15, green 10, blue less than 5
Or
Cool white, red 20, green 10, no blue

Obviously this is very subjective and will very drastically depending on leds and current used.

tterev3
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I ran an experiment on the existing high-CRI mode that MELD has, which just mixes in a small amount of red, green, and blue (equal amounts [by power] of each). To my surprise it really did significantly improve the CRI. It appears that the effect is mostly due to boosting R9 by the addition of some red, so I suspect you could get the same CRI boost by adding red only, although this would change the CCT more than the existing method. Also, the DUV improvement is mostly luck – the white LED just happened to be high of the Black Body Line and was pulled closer by the addition of colors.

Standard High CRI mode enabled
LuminousFlux 134.5 146.1
RadiantFlux 0.4 0.5
CCT 5724 6070
ccx 0.3274 0.3206
ccy 0.3437 0.3334
DUV 0.00365 0.00156
CRI_Ra 70.3 79.9
CRI_R9 -29.9 15.1

It’s pretty interesting to see the added color peaks – blue slightly longer than the die in the white LED (royal blue vs blue), green on the short end of the green from the phosphor, and then red bumping it way up where the phosphor is deficient (in a cool white part). I’ll set it up for red only and see how that affects things.

On an unrelated note, the user-configurable high-speed PWM option is tested and ready to go, I just have to write it up and shoot a quick video demo.

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Facepalm I should have waited to place my order. Oh well, I’m hoping to order more soon anyway. It’s amazing the things you have accomplished with this firmware!
tterev3
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LightRider wrote:
Facepalm I should have waited to place my order. Oh well, I’m hoping to order more soon anyway. It’s amazing the things you have accomplished with this firmware!

If that’s in reference to the high cri option – yours already has that feature! If you mean the high-speed pwm: you can always send a light or driver back to me for free updates.

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