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FrozenGate by Avery

Drivers for 445

It sounds to me like there's no reason not to use an LED driver, considering they can output more amperage and are sometimes cheaper than the Flexdrive and Microboost. I mean lets face it, those two drivers were not designed with the requirements of 445nm diodes in mind, but designed for weaker, and possibly more sensitive diodes. The Shark seems like the perfect choice of driver for people wanting to sufficiently drive these diodes, and has better heatsinking ability. I believe it is going to be my go-to driver from now on for 445nm builds.

I've been doing some testing with mine, and I will post a thread about it soon.
 





x101xtreme said:
I had a quick question about the quality of different batteries for use with 445nm lasers. I have an LG 18650 battery, and if I leave the laser on for long enough, the driver begins to pulse. I'm using a microboost set to 1 amp of current. Funny thing is the battery reads 3.95V on a DMM so it isn't drained.

Is the pulsing due to the fact that the battery is having trouble supplying the necessary current?

If so, should I invest in a more reputable brand like the AW 18650s?
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Depending on age and condition, the LG cell is quality. But, at 3.95V you are only at approx 60% remaining capacity and under that load it is probably sagging to ~3.65V.

According to the manual for the Microboost driver:
(Vout (Volts) * Iout (Amps) ) / Vin (Volts) < 1.2
4.30 (guess at laser diode VF) * 1 (amps) / 3.65 = 1.1780 watts through the microboost. Pretty near to max.

Has anyone ever seen a case where the switching IC for the microboost is heatsinked, and in turn tied to the case of the laser body? Or bench tested with an external heatsink and fan?

I am most interested in finding a buck circuit capable of 1 to say 3 amp adjustable constant current and a input of at least 8.4V

*edit* should be 1.178 amps, not watts. And I am not sure that takes into account efficiency of the circuit, which at best at the voltage is probably 80% and perhaps lower. So, add another ~.25 amps drawn.
 
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Exerd said:
I guess that's where I get a little confused with the mention of capacitors. I know that a drivers main purpose is to regulate current, but I didn't think it relied on the amount of capacitors to perform that duty. See where I'm going?

Basically, I'm trying to tackle the idea of how it would be determined that a laser diode driver is "better" than an LED driver at driving a high power diode. I mean, an LED is a diode, and the 445nm diode is as powerful as many of the LEDs out there. It seems to me that drivers should interchange quite readily at this power level, whether for LED or laser diode.

I merely went along with the idea that a laser driver should be used when possible, but now I'm starting to question whether or not it would even make a difference with these very tough diodes. People are direct driving them, for what it's worth.
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Capacitors are to even out the waveform and to suppress the spikes from battery.
No, cap, dead LD from spikes. Easy to do. done it myself too many times with crappy pointers
 
Oh, yes I have been reading that, sorry if it seemed I wasn't. I am quite familiar with Wayne's drivers. We just haven't confirmed they are safe to use as LD drivers. I don't really know which laser specific drivers I may be missing out on. .I will be bench testing some flashlight drivers for sure, both linear and switch mode.

Please also take a look at George's drivers over at taskled. They are an equally first rate product as Wayne's. The hipCC driver (or now the h6CC) will offer plenty of power for any laser diode imaginable. I built a couple of very nice lights with the maxflex. A 5X XR-E in a 3D and a 4X XR-E in a 2C.

Sorry if it seemed as though I was belittling your posts, there is a very good chance you are onto something. I just don't know enough to state if they would be stable.
 
vegasf6 said:
Oh, yes I have been reading that, sorry if it seemed I wasn't. I am quite familiar with Wayne's drivers. We just haven't confirmed they are safe to use as LD drivers. I don't really know which laser specific drivers I may be missing out on. .I will be bench testing some flashlight drivers for sure, both linear and switch mode.

Please also take a look at George's drivers over at taskled. They are an equally first rate product as Wayne's. The hipCC driver (or now the h6CC) will offer plenty of power for any laser diode imaginable. I built a couple of very nice lights with the maxflex. A 5X XR-E in a 3D and a 4X XR-E in a 2C.

Sorry if it seemed as though I was belittling your posts, there is a very good chance you are onto something. I just don't know enough to state if they would be stable.
Click to expand...

I gotcha. See, that is the whole issue I am attempting to discuss here. Is there a true difference between an LED driver and a laser diode driver here, or is it somewhat make believe? :evil: The only mentioned difference that apparently arose here was the one or two capacitors that are not the same. I'm having a hard time grasping if this could really be making a difference to a 445nm diode.

I know I am not an expert on the subject, but some evidence is all I seek. ;)
 
I have lot of boost converters for flashlights , if they can work with 445nm diode that would be great.
It's not problem even if we have to solder big capacitor to prevent spikes, important thing is that they are very cheap compared to flexdrive or microboost.
 
SpyderFire said:
You dont need evidence , create the proof and call it a day.
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You have to have certain testing instruments to satisfy a "proof", Spyderfire.

If it were as simple as turning on the driver, and observing a constant light output from a diode, I would have all the proof needed. Unfortunately, that won't satisfy some. Admittedly, it's about all the proof I require to run a diode that is as cheap as a 445nm. :D I'm not too concerned about the possible small percentage loss of life that may occur by running an LED driver, if there is any difference of effect at all.
 
ReNNo said:
I have lot of boost converters for flashlights , if they can work with 445nm diode that would be great.
It's not problem even if we have to solder big capacitor to prevent spikes, important thing is that they are very cheap compared to flexdrive or microboost.
Click to expand...

Correct, these LED drivers (buck or boost) should be fine for the hgh power 445nm LDs we now have.
EXERD has already proven the buck drivers can provide the current regulation and power for the 445.
If the primary concern here is filtering out spikes then simply solder a good sized capictor across the LD +/- leads.

Personally, I'm more interested in looking at some of sandwhich shoppe's boost LED drivers as a drop in replacement driver for the 18650 kits. They should allow our 445 diodes to be run off of a single 18650 battery around 750-1000 mA. Can fledrive/microboost do this?... yes. But the boost LED drivers are cheap and MORE IMPORTANTLY will be a direct swap for the old flashlight driver boards... no drilling out the pill or homebrew wiring. Just swap the boards and install your diode/heatsink. If you know your desired mA output and have no need for the adjustability or extreme small size of a DrLava drive, why pay more for it?

When my A140 445nm diode arrives I plan on using one with a drop-in LED boost driver, added capacitor, and long copper heatsink placed in an 18650 host.
 
mAh? that's milliamp-hours... the measure of battery capacity, not necessarily the output current.
It indicates how long a battery can output a current before dying. 500mA output for 3 hours would be 1500mAh.
However, if you draw current quickly you may not achieve the batteries full mAh capacity rating.
Build a constant current circuit and choose a discharge rate. Hook up the battery and monitor the battery's output voltage.
After time, when the output voltage falls below an acceptable level... time (hours) X output current (mA) = mAh
Your application for the batteries determine the minimum acceptable voltage and required current draw.

mAh and max current output are not the same thing.
Batteries with high internal resistance can have lower max current output while having very high capacity.
For example, most people think NiMH rechargables are better than NiCad... generally they are.
but while a NiCad has much less capacity it rapes the NiMH when comparing max current draw. NiCads have very low internal resistance.

High Current High Capacity - Lithium Primary, Li-Lion, Li-Po
High Current Low Capacity - NiCad, Lead Acid
Low Current High Capacity - Alkaline, NiMH
Ultra-high Current Ultra-low Capacity - Capacitors (technically not a "battery")
 
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So is my 445nm with a FlexDriveV5 @ 1.2A likely to pulse with just one 18650?
 
I just set a V5 FlexDrive at 1100mA's (per request) for a 'Hot' option 18650 kit and it is stable at that current even though it does not recommend this in the documentation...

As far as whether the driver will start to have problems (with long 'on' time), I have not tested. But it works well with 445. I tested it on a diode. You can't set the current this high with a blu-ray test load. At that current, the driver won't work unless you are using a red test load... (but it runs the 445 diode just fine - I measured 1200mW's with a 405-G-1)

One thing that will make a huge difference is the quality of the battery. Not all brands will handle that kind of current draw. Probably between 1.5 and 2 Amps... (guessing)

I would recommend spending the money on an AW battery:
AW 18650 Protected 2600 mAh Rechargeable Lithium Battery - New Version
 
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