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ArcticMyst Security by Avery

Odicforce Boost Driver?

honeyx

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Jun 12, 2011
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Just to clarify, it's not an SX1308 IC
Like I said before it's from feelingtech

And I thought you all already know.
Here is the model number:
FP6291

Package marking/identification of SOT-23-6:
ALXYY
Where AL = marking number of FP6291; X = year; YY = lot number/batch

And here is the datasheet:
>click here<

Ok thanks for the clarification. So well, the FP6291 is almost a tuned SX1308 with a OC pin instead of NC. But like Paul stayed correctly in this configuration just a CV driver with a over current protection.

Beside this, the pinout for both ICs is identical and even the reference Voltage at FB, so the same formular can be used to make it a CC driver by using a shunt resistor between FB and GND.

Edit: About your SXD driver results, I have no clue why they differ that much. Owned this driver too. Got it preset from Jordan but even tough the Chips were heatsinked, it died after a month or two and killed the diode as well. But assuming these readings are correct, this could be the reason why it killed the diode.
 
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The SXD driver is a buck driver. If you use 8.4 VDC input, it shouldn't bog down with the addition of diodes in series. I almost never use a buck driver at such a low input voltage. The earlier versions.... the X-Drive is also a buck drive that I use two Li-ion batteries to power.
 
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Which specific driver did you use paul?
I've just tested an SXD driver which i just pull out from a working laser (NUBM07E), the result are just like what i said earlier:


Closed circuit ~5A @ 0V
1Ω 4.58A @ 4.58V
1Ω +1 Diode 3.79A @ 5.24V
1Ω +2 Diode 3.12A @ 5.41V
1Ω +3 Diode 2.43A @ 5.56V
1Ω +4 Diode 1.79A @ 5.71V
1Ω +5 Diode 1.27A @ 5.86V
1Ω +6 Diode 0.75A @ 5.98V
Open circuit 0A @ 6.69V

Would you still call this a current regulating driver?


If I may take a guess, the 1Ω resistor might be too high for high currents.

Just for the sake of the argument, say you are testing it with 5 diodes which have a Vf of 0.6V each, that's an extra 3V to the 4.5V the 1Ω resistor will develop. 7.5V feeding a buck powered by 2 batts is too low. The batts read 8.4V fully charged, under that load they may not even provide the 7.5V, and that's ignoring the wasted heat and voltage drop of the driver.

Since you're willing to test this out let me suggest you either
a) use a 0.1Ω sense resistor
b) test lower current drivers

And, as a final advice, most drivers are not meant to be used on a short-circuit or open-circuit configuration. That might harm them.
 
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I use a 0.1 ohm resistor for checking high currents. I do need to build a new dummy load for the even higher currents using heat sinked 50 amp diodes and my 0.1 ohm 1% 5 watt resistors. I never allow my drivers to be in an open circuit configuration during testing... ever.
 
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i'll try to test it out using 0.1Ω, looks like i totally forgot about that.. :beer:

Btw i know the IC so i do that as a means of confirming the OVP and OCP working just fine.
Everything i did/tested are safe as per specification from the datasheet,

Except if i don't know the IC, yes i'll absolutely avoid any short circuit and open circuit when testing some driver. :beer:
 
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If there's any highlights you guys think I should put in the first post just let me know. A lot tidier that way for those considering these
 

jnrpop

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Hi Z,
This was the conclusion from my testing:

Driver 1: min 145mA max 400mA @ 6.5V out
Driver 2: min 210mA max 410mA @ 6.5V out

Driver 3: min 460mA max 745mA @ 4.5V out

------------------------------------------------------
Driver 1 & 2 was the 0-300mA 515-520nm boost driver from Odicforce
Driver 3 was the 50-1800mA 450nm Boost driver from Odicforce

Someone else will have to confirm if this Driver is indeed CV or CC, i can send High def pics if someone wants them.
My testing procedures, instruments, testload are all setup to the best of my knowledge and ive used the same setup to test other drivers and set them with no problems. Also i must say the other drivers i have set , x-boost, ebay drivers have all acted the same way; change in I with the + or - of Testload diodes :D
 
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I thought this was a case closed condition with these drivers. There is no doubt that they are CV regulators and are unfit as LD drivers. I sent feedback on this driver saying exactly this. I'm done with these drivers for now. If I get the time later, I might try to modify it to be a CC driver. But, as it is now.... it is useless.
 
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jnrpop

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Did u see the driver BBB is using with his 488nm diode? Its $3-5 to buy one from eBay, sold for a 405nm and I could almost guarantee that it would behave the same way if I tested it. BBB has no problems using that driver so far.....I really think we are missing something :D I've just tested another boost driver and had the same results; change in I with a change in Testload diodes.......
 
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The problem with using constant voltage regulators for laser diode drivers is the Vf is held constant while the current is allowed to increase with temperature and current. A driver should hold the current constant while allowing the Vf to change. It might not destroy the diode immediately, but it will eventually.....especially with longer duty cycles. Don't just take my word for it. Ask anyone you respect for their knowledge on drivers and laser diodes. I won't be using mine as configured. If you do, I hope you don't lose it on the first time out.
 

honeyx

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I secound what Paul said. Having a CV driver with a max current limitation isn´t the same like a real CC driver. It eventually can protect your diode from getting killed but due to temperature changes the the current will change and the output power of the diode as well. So all measurments of a common laserdiode will become meanningless by using such a driver. All you can ensure is it´s lasing and hoping the max current limitation will kick in if the diode reaches a specific temperature. So if you want a real CC driver with a constant output for a few $$, better get 10 of the SX1308 for $2 in china and modify them to CC drivers. This is much ceaper and they are doing fine when modified to CC drivers.
 




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