Lava Micro FlexDrive Driver (lavadrive2) fits pens

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

ArRaY said:

my cr123a primaries(?) have 3,3 V... should I just drain them to about 3,2-3,1 V?

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for primaries, you can safely discharge them flat empty, if you ONLY USE ONE CELL in your host, and not two or more. with more than one cell, one can get "charged" with reversed polarity when its empty and another one isnt all empty yet. this can (and will!) result in explosive disintegration.

with rechargeables, a discharge down to 3.0v seems reasonably safe and effective (almost no energy left in). permanent damage wont happen until 2.5v or lower, from what i read several times. still, staying at 3.0v is better, else you have to charge them differently (with greatly limited current), and capacity may be reduced earlier than 2.5v.


i'm all new to this topic too, but read a lot. you should wait for someone to confirm this, to be on the safe side!

hope that helps,

Manuel


ps:
my two lavadrives arrived, cant wait to use them! *happyness-dance*

edit:
of course you wont get much useful energy extra when running one cell down empty:
- there is almost no energy left once the cell drops down to 3.0v
- the lavadrive will shut off anyway at 2.4v

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

I tested my lavadrive on the oscilloscope. At 420mA output, the ripple on the input line (at the driver side) is around 0.06V P-P.



(Thank god that dual-timebase osc's once existed)

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

ArRaY said:

edit 2 : neither diode nor driver failed. They both work fine. Can´t imagine what was wrong. I will build it again today or tomorrow...

my cr123a primaries(?) have 3,3 V... should I just drain them to about 3,2-3,1 V?

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I'm glad you didn't kill it!

You shouldn't have to drain them at all if you use a diode with these characteristics:

When you measure the voltage with the diode in series, you are measuring with almost no current across the diode.  Look at my post above, measure the drop with 50mA across the diode.

http://www.ben.cz/_d/datasheet/1n4007.pdf

This disagrees with the 0.3V statement of the datasheet you found.  Can you link that sheet?

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

ArRaY said:

edit 2 : neither diode nor driver failed. They both work fine. Can´t imagine what was wrong. I will build it again today or tomorrow...

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SWEET! That only leaves a loose connection or a short. Hopefully, when you rebuild it, the problem won't manifest again.

Peace,
dave

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Zom-B said:

[quote author=drlava link=1209418066/440#455 date=1221667681]ZomB, for your test what power supply did you use?  Did you add a capacitor on the input side to compensate for the wires? The ramp-up at 2.4V could be a result of interaction with longer lead wires, or your power supply.

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I used a very stable lab power supply and a 10uf cap at the driver side of the leads. I did notice that there are current spikes at the supply because I had to increase the current knob to about 2or 3 A before it read 250mA. Any lower and the (averaged) current just dropped.

Tomorrow I'll check with the oscilloscope if there are still voltage spikes on the lines.[/quote]


Zom-B, i had the exact same problem on my PSU, even after adding the input cap (and my PSU is well filtered). I also raised the current limiting to 3A, it became better, but not perfect.

Only after i switched it for a battery on short wires, for supply, did everything go back to normal. Then the output current was completelly stable.


However i do like to test the entire input voltage range on my driver, when setting it up, just to make sure the current is stable. (It usually changes <0.3mA between 2.4-4.2V input voltage.) I would definitelly like to be able to do the same thing with the flexdrive. I'll try with larger input caps i guess.

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Yesterday evening, after 4 hours of math learning, I couldn´t stand doing my physics homework, so I decided to give it anotr try, and I found the problem. I did not sand the tail-threads properly enough. After sanding the proper parts of the tailcap and the threads on the barrel and rebuilding the module with the diode and driver, and it worked out nicely.

That thing sure(ly?) is a beauty!!! It is running at 139-140 mA. How many mW´s can I expect? I figured about 115-130, different from diode to diode.

By the way it is the coolest laser I own, compared to the 215mA DIY red that lives inside a plastic jewlery case ;D
But I hope she will soon have a little sister, the goddess of green. (X125) ;D

Krutz, du hast nicht wirklich gedacht das ich eine Batterie komplett entladen wollte und dann die volle und die leere Batterie zusammen verwenden wollte?
Wür natürlich dumm, hast schon recht ;D Hab ich auch nicht gemacht^^

/me is happy, wrote a nice math exam and got a rather good english exam back.+ has a cool lazer. Shoop da whoop!

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

ArRaY said:

Krutz, du hast nicht wirklich gedacht das ich eine Batterie komplett entladen wollte und dann die volle und die leere Batterie zusammen verwenden wollte?
Wür natürlich dumm, hast schon recht  ;D Hab ich auch nicht gemacht^^

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i dont expect anything.. if i dont know someone, i expect the worst
and since there are that many people reading here, and regarding how dangerous wrong handling of LI-cells can be, i felt like repeating that stuff again.. dont take it personal


congrats to your laser! i cant wait for my 803T to arrive!
oh, and congrats for your math-examn as well.. i'll go learn some more math right now!

cheers!

manuel

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Krutz said:

i dont expect anything.. if i dont know someone, i expect the worst
and since there are that many people reading here, and regarding how dangerous wrong handling of LI-cells can be, i felt like repeating that stuff again.. dont take it personal

Click to expand...

I wont.   good that you mentioned it anyway. I thought that I wrote in plural, speaking of the batteries, but don´t know anymore  ;D

Krutz said:

congrats to your laser! i cant wait for my 803T to arrive!
oh, and congrats for your math-examn as well.. i'll go learn some more math right now!


manuel

Click to expand...

I don´t know if you can call it 'exam'. 11th class math klausur. Hope it will turn out good...

Now that my BR is finished, I only need to get the x125, build myself a spirograph, get a little fog-machine,get some other diffraction gratings b/c starfield gets boring after some time, get a 300mW red burner, build another br, hope the 455 488 etc diodes get available for little $$, hope that stronger BR burners come out usw usw.
ah, forgot to mention I need  line/cross generating optics, for liquid sky, and get more great GTID things.

That sure is enogh to do for the next weeks  ;D

*edit* Dr. Lava, I can not find it anymore, but i seem to recall that it would only state small forward voltage drop, and that i somehow merged that with the 0.3 V I measured.
Anyway, it works. I drained both new batterys to 3,1V by lighting a led with them for about 20 seconds...(they started at 3.3V)

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

*sigh* i didnt even use or try the two drivers i already got, and think i'll need to order two more right away.. *laughs*

i want to use one of them for a greenie, because the original driver is too big and of low quality for sure. the output is around 25mw green, the draw from the cr2 primary 3.0v cell is 250mA. i guess the current at the 808nm diode wont be more than those 250mA at the moment? probably even less than that because of strange things the original driver may do? so a lavadrive should be a good replacement, not? hah, and finally a 'pot to turn!
if noone shouts "noo, no lavadrive with that greenie!!1!", i transfer the same amount and way as last time for two drives again?

that will be 4 drivers altogether, for a matched set of 405, 532, 635, 650nm lasers in the same hosts!

Manuel

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Payment sent for 2 lava drives

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

DL did you get my payment or what?

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

HumanSymphony said:

DL did you get my payment or what?

Click to expand...

Hi, no, check your PM.

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Krutz said:

*sigh* i didnt even use or try the two drivers i already got, and think i'll need to order two more right away.. *laughs*

..
i transfer the same amount and way as last time for two drives again?
..

Manuel

Click to expand...

uhm, well, noone answers, i'll just do it now.. paypal sent (in 30 secs)!

Manuel

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Anyone know if i could use a through hole electrolytic for the output capacitor as i broke it off by accident and the value it would have to be.

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

Hi Dr. Lava

I have ordered 2 sets of Lavadrive1 (Groove) Portable Laser Driver Kit from

hacylon.case.edu/ebay/laser_diode/LavaDrive1.php

I have also downloaded the PDF file.

Questions: on the PCB board, which pads are positives and which are negatives?
Also, if mounting LM385 upside down, what will be the orientation.

I am using them for driving a 980 nm laser diode at 300 mA. The voltage should not be more than 3.5 volts. So, using 2 x AA batteries = 4.5 with the driver should be ok? Or should I use a diode to drop more voltage in front?

Hope to receive the units soon.

Thanks!

Re: Lava Micro FlexDrive Driver (lavadrive2) fits

payment sent for a v2 flex drive