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7W NUBM44-V2 over V/I production

Armature

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Hi Guys
I need to protect my 7W NUBM44-V2 from any over voltage and over current as well
I’m using DC-DC CCCV to drive my 7w
I have seen in some page i can avoid any extra voltage can apply on LD by add zener diode but I don’t know the value or number of this Zener diode to be suitable for 7W NUBM44-V2.
Can you please advise?
 



Alaskan

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I had never heard of someone using a Zener diode for this purpose, has anyone else here seen that done before?
 

Alaskan

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D1 is a diode put across the laser diode in reverse polarity configuration, I suppose, to protect it from reverse voltage, but a silicon diode will still allow over a half a volt across the laser diode before it could clamp down on a reverse voltage, for laser diodes, some would fail with even that much reverse voltage, but it is not a Zener diode. I didn't click on the link, just some thoughts without digging deeper.

Edit: I just opened the link and now see what you were saying, although the diagram shown in your post is not a Zener, the article shows a circuit which has one and does not recommend it.
 

Armature

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D1 is a diode put across the laser diode in reverse polarity configuration, I suppose, to protect it from reverse voltage, but a silicon diode will still allow over a half a volt across the laser diode before it could clamp down on a reverse voltage, for laser diodes, some would fail with even that much reverse voltage, but it is not a Zener diode. I didn't click on the link, just some thoughts without digging deeper.

Edit: I just opened the link and now see what you were saying, although the diagram shown in your post is not a Zener, the article shows a circuit which has one and does not recommend it.
In Endurance laser website is it mentioned i will send you the link soon
Also here in Osram laser diode you seen in the drawing there is zener diode connected in parallel
And in date sheet saying that to protect from EDS

0C659D7B-812C-4875-851F-FF115DC10992.jpegF80B546F-BF72-460F-8DF2-35F925832CF9.jpeg0C659D7B-812C-4875-851F-FF115DC10992.jpeg
 

Armature

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I would be very carfeull with this circuit. That is a Constant Voltage driver. Not Constant current. Laser Diodes should always be driven with a Constant Current driver.
I agree
I’m always prefer to use this CC CV DC DC converter
6CC51C63-A91B-4DBA-866C-58B39B513A14.jpeg6CC51C63-A91B-4DBA-866C-58B39B513A14.jpeg6CC51C63-A91B-4DBA-866C-58B39B513A14.jpeg
 

Mosc007

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Never seen a reason for Constant Voltage & Constant Current driver. Constant current is all that's needed for a Laser Diode.

The Diode can't go over voltage unless the Constant current circuit fails or the diode fails. In both cases the Diode is stuffed anyway.
 

Alaskan

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I've seen circuit boards, as above, which allows you to set the top constant voltage, and then adjust current limiting, but for current limiting to work, the voltage would need to be set higher than necessary for the constant current setting to work within.
 

aaronnoraa

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You should perhaps get a Lasorb. Note that this will not prevent you from overdriving your diode, but if you're worried about ESD or current spikes, this is the thing to get. It's the gold standard in laser protection and relatively cheap.. if I remember correctly mine was about 20 dollars.


 




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