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Use pwm led drive for DVD laser diode

gfucka

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Hi,
I'm new in the laser world.
I'm doing a simple laser cutter cnc and now I have to choose the laser.
I ordered one but it not arrive for customs problems... so I decide to use an old DVD and it laser.
I have the attached led driver board with pwm control, it use the PT4115

do you think I can use it to drive the DVD laser?

Thank you so much

ledriver.png
 
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Alaskan

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DVD lasers are so cheap try it, but do you mean a Blu-Ray 405 nm diode? See if you can find the range of voltage this device is capable of outputting as well as the forward voltage and current the laser diode needs and compare.
 

gfucka

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No I mean simple DVD laser diode. How can I find the laser diode information?
 

paul1598419

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The single mode Blu-Ray laser diodes all have a fairly high forward voltage. Depending on the drive current you select it can be as high as 6 volts. But, these are very temperamental diodes and seem to last longer at lower currents......500 mA or less. If you want an engraver that will be turned on and off at high frequencies you would be better off with one of the higher power 445nm to 450nm diodes. But, the higher the power the worse the beam specs.

Also, you will need a better driver than the one you pictured. Try DTR's laser shop online. He sells the X-Woose drivers from Russia that also can be driven with a PWM, but at much higher currents.
 

RedCowboy

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The single mode Blu-Ray laser diodes all have a fairly high forward voltage. Depending on the drive current you select it can be as high as 6 volts. But, these are very temperamental diodes and seem to last longer at lower currents......500 mA or less. If you want an engraver that will be turned on and off at high frequencies you would be better off with one of the higher power 445nm to 450nm diodes. But, the higher the power the worse the beam specs.

Also, you will need a better driver than the one you pictured. Try DTR's laser shop online. He sells the X-Woose drivers from Russia that also can be driven with a PWM, but at much higher currents.

How do you recommend 500ma for a blu-ray diode not knowing if it's a BDR-209 or not ?
Now that cypragon has clowned you do you no longer recommend soft start for 405's ? Not that soft start would preserve a 405nm diode that's not a BDR-209 overdriven @ 500ma as you recommended.
 
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paul1598419

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Of course it is only the BDR-209 that can be run at 500 mA. That is why I said 500 mA or LESS. Since he is planning on using this as an engraver, my recommendation was use a 445nm to 450nm diode instead.

Cyp showed nothing as far as soft start goes. He asked for studies which no one is going to do with these over driven 405nm diodes. My point was that these diodes can be brought up to higher currents slowly in a good heat sink. Trying to use a driver without soft start will kill them at such high currents, so anecdotally using a soft start driver makes sense.
 

Cyparagon

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^The burden of proof is on the one making the claim. The burden of proof isn't on Cyp to disprove your claim. "I killed a few and have established a pattern that no one else has reproduced" isn't convincing.

I don't know why you've got a such a hard-on for this configuration - OP isn't even asking about that diode. This is about DVD diodes which is a good place to start, again, since they're cheap, as is this driver.
 

paul1598419

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I would not have brought it up except that the post before mine mischaracterized what was said so badly. Of course no one has done a study on the rise time of over driven diodes because in industry they are concerned with getting as fast a switching time as possible at threshold currents. No one cares about how to best over drive these diodes with no effort to increase switching times.
 

RedCowboy

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I would not have brought it up except that the post before mine mischaracterized what was said so badly. Of course no one has done a study on the rise time of over driven diodes because in industry they are concerned with getting as fast a switching time as possible at threshold currents. No one cares about how to best over drive these diodes with no effort to increase switching times.
Which still doesn't prove your theory what so ever........lack of data doesn't make your opinion a fact.
 
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