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Freak 445nm Diode?

Wolfman29

Wolfman29

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Hey all.

So I was playing around with my new power supply (got it the day before I left for Alaska, so now that I am back, I am enjoying it), and I noticed something odd when I hooked it up to a 445nm diode I had lying around.

When I set it to CC mode, at around 1.2A of power, my power supply said it was feeding it 6V. That's where it got weird, because I knew that it shouldn't have that high of a Vf.

So, when it was hooked up to the diode, I took a DMM and measured the voltage parallel to the leads of the diode.

For some odd reason, the voltage was a steady 4.18V. That's ridiculously low for a 445nm diode at 1.2A, right? I thought it should be around 4.6V at that high of a current.

Anyway, does anyone have any thoughts? Maybe I got lucky with a freak diode, capable of much more >:D Or maybe it's broked. Anyway, hit me up with what you guys think it is.

EDIT: Irrelevant, I guess. While doing some more testing, it appears that my PSU has killed the diode -.-
 
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Well the high reading of the PSU is most likely due to the length,gauge and resistance of your wiring/connections. You generally want to measure Vf as close to the diode as possible anyway.

The low reading at the diode also indicates you had a lot of losses due to wiring/connections as well and the diode itself probably wasn't actually seeing anywhere near 1.2A.
 
If the losses in the wiring were substantial enough, you would expect to see a higher voltage at the terminal, not a lower one. You would have the voltage drop of the diode plus the voltage drop of the wire.
 
Isn't that what I just said? He said the PSU was showing 6V and it was reading 4.18v at the diode.
 
Yeah, I figured as much. That's what I get for MacGyvering two crappy leads from a $2 DMM to my PSU, because my PSU didn't come with any leads of its own.

Oh well - at least I know the PSU isn't damaged.
 
Wolfman29 said:
Yeah, I figured as much. That's what I get for MacGyvering two crappy leads from a $2 DMM to my PSU, because my PSU didn't come with any leads of its own.

Oh well - at least I know the PSU isn't damaged.
Click to expand...

I generally just buy the connectors and make my own using wire I trust. I've found when dealing with relatively high current levels, most 'chinese' leads suck anyway.
 
I just couldn't find the connectors at Fry's. And I was too stubborn to ask for help :P
 
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