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650nm driver works with 638nm diode?

deadshadow

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hi all,the test load that used on both type of diodes is the same so i was just curious if a driver from 650nm diode can work with 638nm diode,i noticed that on the cheaper drivers for red all of them are listed for 650nm diodes and none of them says anything for 638nm.thanks and excuse me if the question is very nooby or something but i want to know before i try to conect an diode to deep red driver :yh:
 

diachi

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Yes, in most cases you shouldn't have any issues, the voltage drop across them is very similar. As long as the driver can supply enough current you shouldn't have any issues.
 

Radim

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I cannot give you an answer, but what about posting some description of driver and diode you want to use? You might even add the pics of them. It will speed up the process and I'm sure someone experienced like diachi will know.

Edit: Here you go. :D
 
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deadshadow

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to be honest i dont have any specific drivers but i do have an ml501p73 diode and i was curious if i can run it maybe with 2 paraller 650nm drivers.im aiming at around 900-1000ma current it would be easy to achive with 2 red 650nm drivers.im planning to make a semi handheld laser(big) with this diode and tec cooling for the brighest red i can get :) thanks for the reply and help guys,really apreciate it!
 

paul1598419

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You'd be much better off with a single X-Drive from DTR's website than trying to parallel two drivers to reach that current. I can't begin to give you the many reasons that this is a bad idea. If you can't balance the current from each, you'll have one driver conducting more than the other and this would lead to a failure. A single driver is so much easier and safer to use.
 

Benm

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Short answer: if the operating current is the same (or adjustable to your needs) it will work. There is very little difference in voltage drop between a 650 or 638 nm diode, if operating at the same current they can be interchanged without a problem.
 

badboybilly

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You can just use a cheap AMC 7135 driver for the Mitts, 1.050 or 1.400ma are both fine,

I assume price is why your asking and considering you haven't bought any driver yet!
 

deadshadow

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to be honest guys i considered the price because i already bought this driver 635nm-638nm Red Laser Diode Analogue Driver/12V Step-Down Circuit <1.2A Output | eBay from techhood but its completetly dissapointment.i used 5 volt on the analogue slot and 12 volt on the main power slot and the pot doesnt do anything and the output i dont even know but on my test load i read 160ma and once i tried to conect it to the diode gave 1,3-1,4 wich i dont really want to go that high because the diode will be tec cooled and i want to have lower wavelengh.

ofc i sent a message to him and he said he will sent me a replacement,i told if he want to sent me one of the cheaper drivers he has but i think his english isnt that great so he just told me the he sent the replacement.so i just had the idea to use maybe 2 drivers set each to around 400-450ma.

paul1598419 if i use 2 drivers set at lets say 400ma would this cause a problem on the total output because of the difference of the diode's voltage drop that changed on higher currents?
 

paul1598419

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It sounds like you either got a defective driver the fist time, or had a problem with connecting it. I looked at the driver in question and it looks like a buck type step down constant current regulator. I don't see the need to have two separate +5 volt and +12 volt supplies as it should only take the one +12 volt supply. You need to connect the replacement to your test load with a +12 volt supply to the input of the driver and adjust to less than 1.2 amps current. You don't want to use two of these in parallel as the sense resistor in each is not balanced and one would conduct more than the other. I hope this helps.
 

deadshadow

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thanks for the reply,i contact the seller 1st because when i connected the 12v power supply it had zero output,so he told me that 5v on the analoge slot needed to work.after that the driver is working but it doesnt change the output from the pontetiometer.

a small update:just took off a cheap red driver from another build i had and tried it with the mits p73 and i confirm it works good and the max output is 820ma and got around 450mw output with 3 element 635nm glass lens.i hope with a bit more output so maybe ill change the driver later
 
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paul1598419

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Oh, the +5 volts must be for the TTL input. Some drivers have these and all you need do is put the input at +5 volts, negligible current, to activate the driver.
 

deadshadow

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Oh, the +5 volts must be for the TTL input. Some drivers have these and all you need do is put the input at +5 volts, negligible current, to activate the driver.
i tried both to power the +5v only or +12only and it has no ouput.i has to be both connected to get an output that doesnt even be adjustable. maybe the driver is messed up and defective and this happens,i'll know for sure when i get the replacement
 

paul1598419

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I think you may have misunderstood me. The +12 volts is the power to the driver, but the TTL input needs to be held at +5 volts to activate the driver. You need to use both.
 

deadshadow

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I think you may have misunderstood me. The +12 volts is the power to the driver, but the TTL input needs to be held at +5 volts to activate the driver. You need to use both.
i see now,you are right,i just get it wrong.:whistle:
 




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