7W NUBM44-V2 over V/I production

[Armature]

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]

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

 

[Armature]

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

Please check attached picture
And below link

Review of ESD Approaches -- Zener Diode

www.lasorb.com

 

[Alaskan]

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]

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

 

[Alaskan]

Learned something today. Thanks.

 

[Armature]

Learned something today. Thanks.

Thanks a lot for your help

 

[Mosc007]

Please check attached picture
And below link

Review of ESD Approaches -- Zener Diode

www.lasorb.com

View attachment 66030

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.

 

[Armature]

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

 

[Mosc007]

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]

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]

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.

Find out about ESD and how to protect laser diodes - Lasorb

The intention of this web site to serve as a definitive source of information about how ESD and power surges can dramatically decrease the lifetime of laser diodes, and how to help ensure their maximum lifetimes.

www.lasorb.com

 

[cncyana]

Does anyone have a picture of a Lasorb attached to their diode along with the usual diode wires?
Will the back half of a DTR module still fit behind the diode?

 

[gazer101]

Can't imagine getting that (lasorb) to fit nicely into any of my handhelds, maybe for a labby...

 

[cncyana]

Lasorb questions:
1) How wide is the Lasorb device?
2) Can the Lasorb be attached with wires going to the diode pins rather than attaching the Lasorb directly to the diode pins?
In this way, the Lasorb can be hanging out the back of the DTR module and out of the way?

 

[cncyana]

According to the Lasorb website:
1) Lasorb is 10mm wide x 9mm tall with 7 mm long legs
2) Maximum distance to locate Lasorb from laser diode is 10mm to prevent stray inductance.

Lasorb also sells a small chip (3mm x 4mm) to incorporate onto driver board. Are there any drivers which incorporate Lasorb?