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Micro-Drive laser driver by rkcstr

Hey Ryan, I have some old style drivers here, that I'm not sure of teh output. If I give you the markings on the resistors, can you tell me the current?

I would use a test load and a multimeter, but I've lost my multimeter.

The markings are:
1.
750
12r4
br2
br2

2.
33r0
33r0
33r0
12r4

Thanks
Rob
 





Ryan
Just ordered 3 drivers and the dummy load kit from your site, thanks for the discount. :paypal:.
Tymtravler
 
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robjdixon said:
Hey Ryan, I have some old style drivers here, that I'm not sure of teh output. If I give you the markings on the resistors, can you tell me the current?

I would use a test load and a multimeter, but I've lost my multimeter.

The markings are:
1.
750
12r4
br2
br2

2.
33r0
33r0
33r0
12r4

Thanks
Rob
Click to expand...

750 = 75ohm
12R4 = 12.4ohm
33R0 = 33.0ohm
br2 is actually 8R2, which is 8.2ohm

#1 is 422mA
#2 is 214mA
 
WOW Ryan I ordered my 3 drivers and dummy load kit on Friday and got them today (Monday). Very professional packaging, now as soon as I put the dummy kit together and set these BAD BOYS, a burning we will go.
:drool:
Tymtravler
 
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How well will these handle the higher forward voltage of the 8x Blu-ray diodes at high current? I heard the flexdrives were good up to around 300ma for these diodes with forward voltage being around 6 volts at that level. Anything higher than that seems to really stress and wear down a flexdrive as my friend ran his 8x at 320ma and his driver has started to degrade as his laser output dropped from 420mw to 260mw. He checked his driver and noticed that its output dropped to ~270ma and he could not adjust it any higher.
 
I can't say much about the flexdrive and it's upper limit of voltage output capability.

For mine, the regulator IC is capable of up to 15V input voltage and the driver rating is 12V, so subtracting the required operating voltage overage, that means my driver should be capable of around 9.75V maximum output voltage while maintaining regulated current.

So, I don't know what voltage the 8x diodes run at high current, but my driver should have no problem so long as you provide sufficient input voltage to maintain regulation.
 
If I remember correctly some of these 8x diodes were pulling around 7v at ~400ma but I believe daguin ran into some problems with his rkcstr driver when he began testing the Pioneer 8x diodes. I'll have to check his thread again to see what exactly he was encountering.
 
Yep, according to his tests in March his rkcstr driver appeared to have some difficulties with the diode above 300ma. This was with an older driver so I would hope that the new version to not have the same difficulties. The real question would be the power source in a handheld host! I'm guessing three 10440s would do it... just gotta find a host that uses three triple A batteries.
 
For 7V output you'll need at least 9.25V input voltage, ideally over 10V to allow some overhead, especially with batteries. Theoretically, 3x 3.7V lithiums should be enough voltage, but I haven't tried it personally to tell you for sure they will work. It could be that the dropout voltage of the driver increases at that high of an output voltage and therefore the input voltage requirements of the driver also increases. It could also be that the lithium batteries voltage is dropping while under load, enough so to drop below the minimum required voltage for the driver.

If I get a chance on Sunday, I'll see if I can test a driver out with a >10VDC wall adapter on a load that is ~7V and see what happens. If it works fine, then it is probably the batteries, if not, then the driver.

Or, if you're not happy with the driver, you are welcome to return it for a refund.
 
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Hey ryan - Am I right in thinking that I can run a pot in series with your driver to change the current once the max is set on your driver, so I can control the current from outisde the host?

Thanks
 
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