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Test a diode?

lasersbee

lasersbee

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rkcstr said:
I'm sure you understand the physics better than I do, but that was just the general guidelines most agree on. Sure, it may not happen, but why take a chance? It takes a second just to make sure. And, who knows when someone here who isn't very experienced with working with these electronics does something unusual and creates a condition where it is more likely to happen?

So, it's just a "safety precaution" mostly. Not saying that it killed the diode because it wasn't done.

Certainly an intermittent connection between the diode and driver are more dangerous. The version previous to this most recent lavadrive had a zener on the output as protection for open circuit to prevent over voltage on the output, but I'm not sure what it employs now. Also, when you get an open circuit, I imagine you'll have a fully charged cap that will have no problems sending a rush of current through the diode when it is reconnected.
Click to expand...

I agree... better safe than sorry....:undecided:

If the FlexDrive output has an intermittent connection to the LD...
during the intermittent "open circuit" condition the FlexDrive will
try to increase the no load current by increasing it's output voltage.
when the intermittent "closed circuit" condition comes back... the
output cap (that has just been charged to and over-voltage) will
discharge into the Laser Diode... A very good chance that it will
blow..
Been there... done that... :eek:


Jerry
 





dr-ebert

dr-ebert

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I'd first verify the current the driver is putting out.

If it checks out ok, and you're very brave (or feel lucky), you could next set up your DMM to measure the output voltage of the driver, disconnect the load while it's powered and look what happens to the voltage (how high it goes). BUT REMEMBER, THIS MAY KILL THE DRIVER!

If you don't want to do that (I wouldn't), I'm out of ideas currently.
 
chipdouglas

chipdouglas

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you don't mention how you are setting your driver. did it come pre set or are you using a dummy load. A dummy load could build up the cap to an unsafe level even for blu-ray. If we are looking at it from eberts view.? :whistle:

michael
 
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