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Quick Diode Test without driver?

Hemlock_Mike

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After reviewing my data, the diode will be lucky to draw 300 mA at 3.7 applied volts. at 4.2 volts, 900 mA. YMMV. Use the resistor. Look at the data from the experimenters.
How many people posting here are hands-on DIY with test equipment?
HMike
 



lasersbee

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Some guys wanted to resell diodes with me, but they lack the skill to solder an DDL driver, and i dont want to send them some to little-timbuktu ;) So i hoped for a kind of battery, which is so weak, that the maximum currenty would be just enough for see it glimming.

What bothers me about this statement is that you say your
buddies lack the skills to solder a simple circuit... but you are
going to unsolder the pins of the LD atached to the PCB...:thinking:
Without any soldering skills... you may be killing your LDs
before you get to test them...:cryyy:

Jerry
 

vegasf6

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As these can take up to 2A without instantly dieing; can you recommend me a kind of Battery which i can use to quickly (for a very short pulse to see if its working) so they dont overheat. I just want to test the harvested diodes fast, dont have a good driver here atm. some Button/Lithium cells maybe?

If you really need to do it down and dirty you could probably get away with 3xAAA or better yet, take apart a 9V alkaline and try ~3 or 4 AAAA cells.
Use the smallest gauge wire you can find, preferably a 28 or 30, and use long test leads, at least 12". It will act as a rudimentary current limiting device.

I do agree with John though in that you would be better served with at least a resistor in series. Or a 100 ohm pot if you have one laying around. Or a amc7135 driver. Or, as stryopyro said, the lm317 and a resistor. You must have a local Radio Shack.
 

Bionic-Badger

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Just wondering here, is it unsafe to use machine pin headers in place of solder permanently on the diode? As in making a quick disconnect module swappable laser?

I used machine pin headers on my 445nm diode build, though I haven't done any really long-term tests with them. I also hot-glued the header connector to the back of the diode for support (should be done even with solder).

I wouldn't risk a "quick disconnect" module without any protection circuitry (like diodes and maybe a capacitor. Also the header socket grippers, though very tight when new, may start to loosen with too much use. I expect the sockets in the headers I used will form a sort of "stuck" grip from the continuous pressure they're applying to the diode pins; that may not form from repeated use.

Connectors like these may be more appropriate.
 

Xer0

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Dec 2, 2008
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you say your
buddies lack the skills to solder a simple circuit... but you are
going to unsolder the pins of the LD atached to the PCB...:thinking:
Without any soldering skills... you may be killing your LDs
Na, they would just cut off the ribbon, not more :)
 

Xer0

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It would at least LED at that current... but i dont see a 3-pin-socket :-S
should be something more for wired ones i think...
 




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