808m Shorted?

[High_Octane]

I have a 1000mw 808nm LD that is shorted.
What I'm wondering is...
What is more likely:

• The LD was faulty from the factory?
• I screwed it up?

I can see burning one out "OPEN" but not shorting one.

anyone care to enlighten me?

 

[pseudonomen137]

Honestly, its more likely you screwed it up. What do you mean its shorted though. When you apply voltage it tries drawing as much current as it can? What connections are you hooking it up to?

 

[High_Octane]

Honestly, its more likely you screwed it up. What do you mean its shorted though. When you apply voltage it tries drawing as much current as it can? What connections are you hooking it up to?

Yes, it does act like its drawing alot, When I put an LED in the circuit, and then connect a feed wire to the LD the LED goes out almost like the LD is shorted rather than pulling a load?

The polarity is as follows
.---> Ground
Positive<--------- . . ------> Nothing connected
When checking the positive and negative pins on the diode with my Meter set to Diode it reads .016 no matter which way I connect the polarity.

 

[pseudonomen137]

What are you using as your power source?

 

[High_Octane]

Powered by a rat shack variable Power supply " 1.5- 12v 300ma, set at 4.5v, to my DDL's circuit.

 

[SenKat]

High Octane - I THINK you may have the pinout incorrect. Most of the 808nm diodes I have seen are CASE positive - which is opposite what your diagram shows - the pin that is grounded to the case pointing at the top would be positive, and the one to the left would be negative....I think you reverse voltage killed the diode perhaps ? Check it out, man....I have never seen a case negative 808nm diode...

 

[LarryQ]

Senkat beat me to that one...
I was playing with an 808nm diode and it was indeed case positive!



 .---> Positive
 Negative<--------- .     . ------> Nothing connected


On the good side..I did connect mine up backwards the first time I tried it..simply changing polarity, and it fired right up!

I hope yours is still OK..it sounds like a BEAST!!

LarryQ

 

[pseudonomen137]

Powered by a rat shack variable Power supply " 1.5- 12v 300ma, set at 4.5v, to my DDL's circuit.

Nah, not gunna cut it unfortunately. To something meant to put out 300mA, it might as well be a short. I can't remember the exact spec off the top of my head, but I believe your diode alone is intended to draw ~1.5-2 AMPS at ~2V? If you're using a DDL LM317T circuit, its not gunna be able to handle that type of draw either.

And also, see what SenKat said. Perhaps that will help get you started.

 

[shikari_rock]

I have a 1W IR diode, it's meant to draw 1400mA at 2.2VDC.

 

[High_Octane]

Thanks everyone, I have a adjustable Diode Power Supply "Ebay" on its way. That should handle the voltage/amperage problem, Now I need another diode.
You would think they would give you the pin out information somewhere between advertising and when you receive the damn thing.
Oh well That was like burning money :

 

[High_Octane]

You know what, I just hooked it up as SinKat said too and it flashes a bit of red!

I believe its still alive ;D

Won't be able to test it till my PS shows up.

 

[High_Octane]

Damn... In the last few se3conds, some GD ebay sniper outbid me by 1 dollar!

So I bid on another. Till then I want to build my own.
I have a RS 12v 1500ma Power supply. WHat do I nned to drop the voltage and amperage to
2.2v 1000ma?

 

[Greenie]

While we are on the subject. Is it just the 808 diodes that are case positive?

 

[Aseras]

almost all bare diodes are case positive.

 

[a_pyro_is]

Still kind of OT sorry.
So it's usually just the DVD burner diodes that are case negative? Or am I really On-Topic and you meant bare near IR diodes are case Pos?

 

[High_Octane]

almost all bare diodes are case positive.

I'm confused as well. My diode is in a can.
So, how does one determine the polarity or what is the general rule of thumb on certain diodes and their polarity?

Oh and can someone tell me how to drop from 5v to 2.2ish without dropping my amps?

Thanks