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ArcticMyst Security by Avery

BlackBuck 8M 8A Modulated Buck Laser Diode Driver + External Pot

94Z28

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BlackBuck 8M - 8 Amps compact driver for portable devices

*Note if you want to order one of these, contact me within the next week as I am placing my order and you may can get a couple dollars off by ordering with me. (I'll order them up front, and sell you one at the initial price; Otherwise, they'll be in the BST section shortly)

The brand new high-performance, compact buck LED/laser diode driver with thermal protection (external NTC sensor) . Can be controlled/modulated by an external sources like DAC, PWM or analog modulated signal. It has 5V reference voltage output for connecting an external potentiometer as a modulation source. High-quality onboard multi-turn trimmer helps to the fine-tuning of the output current. The driver can operate with the current up to 3A without an external heat sink, but it requires a heat sink for currents above 3A. It works fine with 2 or 3 cells Li-Ion or Li-Po batteries or 7-12V DC PSU.

BlackBuck8M1-0_zpsbk4nkixd.jpg


Specs:
Output (drive) current 1000... 8000 mA +/- 5%
Modulation input 0...5V or 5V TTL/PWM
Conversion efficiency >93%
Modulation rise/fall time 40/60ms
Start-up delay 30ms
Sine-wave modulation bandwidth 4 KHz
Overheat protection shutdown t° 50° C / 122° F +/- 5%
PCB dimension 16*17*6 mm

This is the setup i'll be using >
BlackBuck8M1-1_zpseozzrncs.jpg



So I got a BlackBuck 8M in from X-Wossee finally and decided to give it a quick try on a M140 i had on the workbench still inside a lab style host.
xfs13o.jpg

zv297b.jpg


I didn't solder everything together because this driver isn't done being tested, I'm going to test it on the higher current diodes as well. Anyway, the clips got connected and everything readied. I turned the external pot all the way down, and plugged my test load onto the end of it; He pre-set it at 1.8A before shipping it to me. I am going to run through all the numbers again later tonight at work but it looks to be 93-94% efficient when looking at input to driver, and output to LD.

Hooked up the power, began slowly turning pot up... It slowly rised eventually the pot bottomed out at a perfect 1.79A. It was time to hook to the LD! So I did hook it up, and in the process i placed a thermocouple on the IC of the driver to monitor temperature change.

Begin/Ambient Temperature was 88*F after running for 5 minutes 96* and 15 minutes was 99*F. It has very little heat rise at 1.8A i was really happy with that. I don't know how well it will do at 4.5A yet but soon I will find out; I would guess a heat sink will begin to be required up around that area.

This driver will be awesome for some guys who want an adjustable output! I know it would be great in some of those maglite hosts and the "external pot" could easily get mounted in the head somewhere!
zklt2t.jpg



Now, who has some build ideas!
 
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I saw that driver on ebay too, very nice, but I thought I'd raise a question about adjusting the driver. I've been adjusting the pots on my drivers by having the pot turned down, turning on the power, measuring the current and then, turning the power off and readjusting the pot a small amount upwards before turning back on to see how much change I've made. This way the pot is not adjusted while power is being supplied. The reason I adjust my drivers this way is I've heard from others they have blown their diodes when adjusting a driver pot with the diode attached. The reason for the precaution is a resistance spike from a noisy pot, or a pot which isn't adjusting smoothly without ripples can damage a diode. Others use a dummy load resistor with voltage dropping diodes to mimic a laser diode and set the current that way, then inserting the diode after the desired about of current is reached.

I don't know if this precaution is really needed, what say, opinions on this matter?
 

94Z28

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I saw that driver on ebay too, very nice, but I thought I'd raise a question about adjusting the driver. I've been adjusting the pots on my drivers by having the pot turned down, turning on the power, measuring the current and then, turning the power off and readjusting the pot a small amount upwards before turning back on to see how much change I've made. This way the pot is not adjusted while power is being supplied. The reason I adjust my drivers this way is I've heard from others they have blown their diodes when adjusting a driver pot with the diode attached. The reason for the precaution is a resistance spike from a noisy pot, or a pot which isn't adjusting smoothly without ripples can damage a diode. Others use a dummy load resistor with voltage dropping diodes to mimic a laser diode and set the current that way, then inserting the diode after the desired about of current is reached.

I don't know if this precaution is really needed, what say, opinions on this matter?

This driver has a maximum current pot, and then it has an external pot. It's safe to use the external pot, the same port can also be used for TTL modulation, or just wired together to make it only read off the "maximum" pot. I tested this on my dummy load before, and it seemed to turn up just as it should. It never exceeded the 1.8A setpoint but I don't have a way to log what it does in millisecond increments, and my DMM isn't going to be a high enough resolution to catch a spike probably. I wouldn't recommend doing it before verifying via a dummy load but I would integrate this pot into a build to have adjustable output; You could turn the switch off, turn it down, then power back up if you wish to be safe... it's adjustable what is not to love! My M140 works great powered by it.

My only question is how safe is it to decrease current below output threshold and still have power enabled? I don't know if it's bad on the diode to have a current lower then the threshold current; research time. It's obvious when you are nearing that point though, and I wonder if using a different pot would limit the amount you could decrease (without limiting you getting back to max setpoint).

We will use this thread to discuss this driver, and I will be ordering some and have them on-hand in the United States. If anyone wants to order one at the discounted price included in my order, then please PM me. There will also be some small 3A ones that are tiny enough for small builds (should fit in an Aixiz module).
 
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Thank you. Sure is a nice driver, seller doesn't seem to indicate the amount of drop-out from the device. If it is a buck, the efficiency depends upon how much voltage the unit is turning into heat to maintain the amount of constant current the device is set to produce/regulate. Even so, if you are measuring that amount of efficiency for the diode you are using, the drop-out voltage must be fairly low and the diode well matched to your supply voltage. Efficiencies that high are common to switching CC regulators, so when I read that, I began to think the device was a switching regulator or some kind of hybrid until I looked back to see it was indeed a buck, how could I miss that with a name like blackbuck.
 
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94Z28

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122 F sounds low, is it 122 C for the temp cut off?

Not sure, but I am gonna try to find out soon. I'll see about running it up past that soon. It's very good with handling heat though, I am shocked myself. I don't have any heatsink on it either... I Really like this driver for any MagLite or MX900 build and i got some of both incoming in the mail on deals from eBay..
 
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My idea of a buck might need some updating, looking at the photographs this sure looks like a switching regulator, that would explain the high efficiency. I just never considered switching regulators bucks because they convert voltage, instead of turning the unwanted voltage into heat. As long as the device reduces the voltage, I see no reason not to call it a buck, my bad.
 
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Bucking and boosting both use an inductor and are switching, some are buck and boost, a lot of electronics today will run on whatever battery you have.
 
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I've built what I consider true buck voltage regulators using a single transistor and a couple of resistors and small capacitors, no inductor and not switching. I've also home brewed my own "buck" circuit using a simple IC linear regulator which wasn't switching or converting, didn't use an inductor. If you say buck "converter", to me this changes the meaning and now you are talking about a DC-DC switching converter with an inductor of some kind.

My disconnect was because I was thinking of a buck as simply a linear voltage regulator (with CC control loop) instead of a DC-DC switching converter, to me the word buck should not be used for those because they are converting the voltage, not really "bucking" it through a pure voltage drop. However, convention is what it is, and I must take a back seat to call converters bucks, since that is what people are calling them, but I will say this, they don't buck anything any more than a transformer does and because of this and the high frequency they run at, are very small as well as efficient!

Although not being debated, due to my mixing in mention of a voltage regulator, I will add this, a constant current regulator is simply a voltage regulator with a current feed-back loop (voltage drop across the sense resistor) tied to it to vary the voltage until the desired amount of current is achieved, keeping the output at that voltage until the load resistance changes, requiring either lower or higher voltage to keep the current at a constant amount.

I don't want to hijack the thread with this. I do have a question to add though, X-Wossee has made drivers before and once he is out, he doesn't have more. Do you know if he will have more of these later? He seems to build these as part of a college course or something, not sure.
 
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94Z28

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From what he told me this is the newest style, along with the 3A i was told about; This is what he is manufacturing now. The older versions are out-of-date and this is his latest product. I will find out for sure how long the production run is; either way they are very nice drivers and worth it to pick a couple up.. Never know when the next diode comes out that may require an 8A input.... I am asking him about your question Alaskan.
 
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I checked out his ebay store and see he has several drivers, I guess he's in the driver business now. He only had one type of driver the last time I checked and then ran out of them. Thanks for checking for me.
 
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I'm not sure if you herd but the green prototype boards have a falt, it won't damage your diode but this is what is the issue, (I found a defect in green boards, this is caused to incorrectly matched dielectric in one of capacitors. ) so they could stop working but the blackboards are fine, I was told Flaminpyro will have these soon also, they are awsome drivers though, posted a build in the green thread V4 lightsabre but I am yet to add an ajustable pot as the ones I ordered and recieved are way too big!

http://laserpointerforums.com/f45/v4-lightsabre-ndg700-blackbuck-m8-98311.html
 
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94Z28

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I seen that driver in your build Billy I will be getting the black boards and only testing on green prototype.
 

AaronT

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This begs to be utilized in conjunction with the Hyperion LPM to make a poor boy diode testing special.

Unless someone beats me to it ,I should have a thread on it next month.
 

94Z28

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AaronT that would be a decent idea but I prefer the other X-Wossee driver because it has a "quick current check" connection on it. I have burned up my old variable PSU and have a new one that will arrive on monday so it will be all fine. Hope you got something to monitor current while testing!

Also, if ANYONE wants to get a BlackBuck 8M driver better PM me before Friday the 16th as I am paying the invoice for the drivers then. They are available at a discounted rate for my initial order only, this will take some of the strain off of me by buying in bulk and if you can help by taking one of two that will be great! Thanks.
 
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Very interesting driver. I like the external pot ant T control by NTC sensor.
Does it come with 10k NTC sensor which could be replaced by 10k NTC sensors of other shape?

But I have a question ebay specs do not answer: What is the maximal voltage it can produce?

I mean for driving 2 PBSed 07Es in series I currently use the cheap dx.com driver set at 4.5A at 9-10V. The input voltage of the driver is also 12V (max 13V). If this X-wossee driver can hold 8A at 5V (what makes 40W), can it do 4A at 10V (which would be same 40W)?


Edit: I do not have a test load, so in order to test drivers to feed 2 NUBM07E in series (3.5-4A at 9-10V) I have soldered 5 half-Ohm ceramic resistors to a Voltammeter from dx.com in this way on picture. Then red and black wires to driver output. The resistors heat like crazy but this is what they are made for.

OK, it looks like I need to write a new post to add picture.
 
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