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FrozenGate by Avery

The Little Diode That Could






paul1598419 said:
Actually it is the current you are running it at in mA. The voltage, or Vf is not meaningful.
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I guess I should clarify. These don't have driver circuits. Because they are so cheap, they only have a 92Ω resistor. The Vf of the diode is 1.834V and I'm running it from a 5V constant voltage source.

When I said the rated 5V, that's because that is how they advertised it. I don't have any real way to test the current draw without disconnecting the diode.
 
Javalin said:
I guess I should clarify. These don't have driver circuits. Because they are so cheap, they only have a 92Ω resistor. The Vf of the diode is 1.834V and I'm running it from a 5V constant voltage source.

When I said the rated 5V, that's because that is how they advertised it. I don't have any real way to test the current draw without disconnecting the diode.
Click to expand...

You can still figure out the current coming through the diode if you know the Vf of the diode. Subtract that from the 5 volts to get the voltage drop across your resistor and use Ohm's law to get the current.

I just did it for you. I=0.034 amps or 34 mA.
 
paul1598419 said:
You can still figure out the current coming through the diode if you know the Vf of the diode. Subtract that from the 5 volts to get the voltage drop across your resistor and use Ohm's law to get the current.

I just did it for you. I=0.034 amps or 3hat is the measured Vf of the "other" diode of the same type, I'm not well versed in
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paul1598419 said:
You can still figure out the current coming through the diode if you know the Vf of the diode. Subtract that from the 5 volts to get the voltage drop across your resistor and use Ohm's law to get the current.

I just did it for you. I=0.034 amps or 34 mA.
Click to expand...

That is the measured Vf of the "other" diode of the same type. And correct me if I'm wrong but won't the Vf change with temperature?

I'm admittedly not well versed in the voltage characteristics of laser diodes, ohms law I've got down, but I thought they didn't obey ohms law as they aren't linear.
 
Measure the voltage drop on the current limiting resistor. You then know E and R so Calc I
 
Javalin said:
That is the measured Vf of the "other" diode of the same type. And correct me if I'm wrong but won't the Vf change with temperature?

I'm admittedly not well versed in the voltage characteristics of laser diodes, ohms law I've got down, but I thought they didn't obey ohms law as they aren't linear.
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I assumed that was the Vf of this diode. If it has been running for years it is as hot as it is going to get so, no that won't be a factor. You are measuring the current through the resistor which is in series with the diode. The current will be the same through both.
 
Javalin said:
It was so little power to begin with that it's hard to really tell. In a daylight lit room, on a wall 15 feet away the dot is still easy to see.

My power meter didn't even register this thing years ago when I tried. Since quantifiable data aren't available, and given the 10 years that it's been, I would say it seems more dim,

Real time edit. I just checked it side by side with the last unused diode from this batch. Power output has reduced significantly.
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Do you think it could have LED'd?
 
87,625 hours! We made it 10 years! I'm not sure what I expected when I started this, but I never thought I'd be writing this post.

Ten years, so much has happened in that time. Even though most of my laser projects were placed on hold, this gave me a reason to come in here and check up on things. I still have most of my projects in various states of completion and hope that with the new house I'll have a safe place to start putting them together.

Thanks to everyone who has encouraged me to stick with this crazy pointless project.

Just a note. We are moving this week and I purchased a new massive UPS that should power this little guy for months. I'll be hooking it all up before moving so there will be a short few seconds that it will be out while switching it over.
 
Can you calculate how much power it has consumed during these past 10 years? That's crazy though. 10 years of continuous use!
 
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