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Thread: Lasorb VS. TVS

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    Default Lasorb VS. TVS

    What does the lasorb ESD protector do that a TVS doesn't?

    some datasheets to reference:

    http://www.lasorb.com/LASORB_L44-683-X.pdf

    I'm not saying that the following transient voltage suppressors have the correctly matched breakdown voltages, different laser diodes have different forward voltages. There would be some details, like how much leakage current you care for etc.

    http://www.mouser.com/ds/2/427/icte-240324.pdf
    http://www.mouser.com/ds/2/308/1N6373-D-102888.pdf


    A schematic for an array D1 - D4 would break down a little above your forward voltage of each diode, D5 would breakdown little above the total sum of the forward voltage of the laser diodes in series.

    Click image for larger version. 

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    Quote Originally Posted by lightlinked View Post
    What does the lasorb ESD protector do that a TVS doesn't?

    some datasheets to reference:

    http://www.lasorb.com/LASORB_L44-683-X.pdf

    I'm not saying that the following transient voltage suppressors have the correctly matched breakdown voltages, different laser diodes have different forward voltages. There would be some details, like how much leakage current you care for etc.

    http://www.mouser.com/ds/2/427/icte-240324.pdf
    http://www.mouser.com/ds/2/308/1N6373-D-102888.pdf


    A schematic for an array D1 - D4 would break down a little above your forward voltage of each diode, D5 would breakdown little above the total sum of the forward voltage of the laser diodes in series.

    Click image for larger version. 

Name:	laser-diode-array.jpg 
Views:	41 
Size:	78.8 KB 
ID:	46571

    i always assumed the "orb" in lasorb stood for transorb.
    suppose you're thinkin' about a plate o' shrimp. Suddenly someone'll say, like, plate, or shrimp, or plate o' shrimp out of the blue, no explanation. No point in lookin' for one, either. It's all part of a cosmic unconciousness.

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    I seem to recall from somewhere (maybe a SELEM of years past) someone (maybe Bill) saying that the LASORB is a combination of preexisting components that were packaged together. I don't know how accurate that is (or how accurately I remember hearing that) or if it still holds true but I wouldn't be surprised if there was a TVS or something similar inside.

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    A Lasorb dumps a transient over 100X faster then a classic Transorb. Which is why it was invented. For many Transorbs, the laser diode will be blown before the Transorb is conducting. Think tens of nanoseconds...

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    I always thought the "magic" of the lasorb was a low-inductance package for a transorb that could be placed right at the laser. The actual semiconductor in a normal transorb clamps in picoseconds, which is faster than a transient can reasonably be if there is any inductance between its source and the laser diode. Actual clamping performance is limited by the package inductance. Typically silicon protection devices (like transorbs) are the fast part of hybrid surge protection that clamp very quickly before MOVs catch up and dissipate the bulk of the energy.

    I'd be interested to learn what else is in the lasorb (capacitors to counteract inductance? a small MOV? something else entirely?)

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    I'd be interested to learn what else is in the lasorb (capacitors to counteract inductance? a small MOV? something else entirely?)
    See a patent by William R. Benner assigned to Pangolin, Inc..

    There is at least an R, a C, and a Semiconductor. Possibly some more.

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    patent 8,902,557

    ah... so its a crowbar. the patent explains it all, surprisingly in plain English with none of the run around legalese

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    Well, I am pretty impressed with the Lasorb. I have used them for years and always harbored a little doubt that they were more of a good luck charm on the more robust diodes. But, recently I was suffering from some mysterious deaths of inexpensive low voltage pulse generators in a recent project where some REALLY high voltages are being used to trigger flash lamps by creating fields within bulk cavities. There is some unavoidable EMF leakage and I suspect some momentary ESD that I have been unable to track down. But, a couple of the new high voltage (15V) Lasorbs across the power and pulse leads and thousands of pulses later...still going strong.

    Thanks Bill

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