Inexpensive ESD (static) protection.

[Markus Unread]

As long as all three parts are at the LD, it won't hurt to use the R/C/TVS combo.

 

[kiyoukan]

Great these should help my lab builds alot thanks.

 

[Bionic-Badger]

Have you tried adding a MOSFET in series with the diode, in addition to the TVS? Something like this. Just tune it for the pulse duration.

 

[jib77]

^^^ Nice find!

 

[kiyoukan]

now that would be nice and maybe beat the lasorb.

 

[Bionic-Badger]

now that would be nice and maybe beat the lasorb.

I wouldn't be surprised if the MOSFET weren't the "special diode" in the LASORB, either just passing current on a large voltage transition, or blocking it as in the paper above. Hell, a MOSFET is essentially constructed of diodes anyway.

 

[lasersbee]

I wouldn't be surprised if the MOSFET weren't the "special diode" in the LASORB, either just passing current on a large voltage transition, or blocking it as in the paper above. Hell, a MOSFET is essentially constructed of diodes anyway.

I would tend to agree.... since the Lasorb holds the protection for
a specified period of time after the 1st event...


Jerry

 

[izzzzzz6]

Hi. Did anybody ever decide weather or not Unidirectional diodes were a good ESD protection or not? If so what is a good value diode to use to protect a Nichia NDB7875 445nm 9mm Laser Diode In a Copper Module? I was thinking to set the input power to the driver at 7v and limit the current to 1700ma. As ESD protection i was planning to use a DIODE, TVS, UNI, 5V, 400W, SOD123W, Part # PTVS5V0S1UR | eBay
Unidirectional diode with breakdown voltage range of 6.4V - 7.2V with a clamping voltage of 9.2V.
I was also advised to use a schotteky diode across in the circuit.
Does anybody have experience here or perhaps someone knows where i can look at circuit diagrams to get a better idea of how this setup works? this way i can build my own ESD protection from scratch. Thanks.
James

 

[Cyparagon]

TVS diodes are connected like a protection zener is: reverse biased and in parallel with the laser diode.

 

[hakzaw1]

Hehe.

How many people have tested the solutions being proposed here in the real world?

Common ESD devices made to protect semiconductor products won't work for Laser Diodes. If you want to understand why, see this page:
LASORB - ESD absorber for laser diodes

We have tested TVS as well as multi-layer varistors and other approaches. They won't work for laser diodes. LASORB is the only thing proven to be 100% effective at preventing laser diode failure caused by ESD and power surges. And it's only $2 if purchased in large quantities...

There is a wealth of information on the LASORB web site, including videos showing how well it works, and pictures showing our test bench.

Best regards,

William Benner

Since the last post LONG AGO more work has been done on LASORBS AND iirc they already have on for the green diodes-

I tend to believe that home=brew version of LASORBS for most hobby level folks may not do the job as well- if it were all that simple-easy and cheap maybe someone can explain to me why big makers of lab lasers like CNI are now using LASORBs- but I know very little than most of you guys.

I do think I remember reading that the Lasorb (and very likely any homemade version) needs to be mounted as close the the can as possible,
I dont know why but tend to trust those who know more-
ALSO I really think any question any may send to Bill will get an honest answer - and HE WILL reply even tho he is often very busy.

About the price of $8 and shipping- Pangolin is often the highest priced
on their products as i really think they prefer we do biz with an authorized Pangolin dealer like AixiZ. and others.

If you really want to know more about this subject reading all that is a Pangolin.com is a good idea.

Lots of the PLex pro builders of modules and projectors use LASORBS.
And i have yet to see ANY use home-made ones.
but what do I know......0000lol