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FrozenGate by Avery

Need help on extracted diode

daawood123

daawood123

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Mar 5, 2012
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Hi

so a little while ago, i decided to take out the drive in my old laptop to see if i could find any diodes, i took it all apart, and i found a small brass heatsink, i didnt think much of it then, so i put it on top of my wardrobe

now, about 2months later, i picked it up and saw it had 3 pins at one end,i got excited, and proceeded to solder off the solder and the PCB thing attached to the pins, then i tried pushing it out of the heatsink, but it was glued in tight, so i grabbed my dremel and a small file, and long story short, i grinded the sides down and out popped a diode, it has like a silver can on the top, and the lens is slightly tinted blue if you look at it from the right angle

i dont have a camera otherwise i would have added pics, but i dont know if its bluray, red, IR, or most importantly, if it is still alive. i kept the soldering iron on for about 5seconds max, however, the grinding bit on my dremel really heated that heatsink up, i didnt grind it with the grinding stone for more than 3-4 seconds. anyway, i have the bare diode now, but i dont know what to do, should i solder wires on? i dont even know which is positive, negative and case, but like i said, the lens has a blue shine to it if that helps.

any help would be much appreciated

EDIT: i have hammered the diode into the aixiz module head i had lying around ( with the back part of the aixiz ofcourse, i didnt hammer the diode itself)
 
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Blue lens is probably IR or red. Was it a burner or just a cd drive? If just a cd / DVD and if there was only one diode it's probably a low powered 650nm red. Most you can drive to 90mA or so without damaging them. You can find the pin out with a multimeter on the diode check range. It will read a few volts forward when the probes are on the right pins.
 
um, the laptop i had probably had a burning feature. do infrared diodes have the can iswell?
i have put it into the aixiz head, ill try finding out the pinout, i have used my multimeter for testing LED'S before, and if the correct pinout was acheived, the LED's would switch on with a very dim light, will this happen to my diode iswell?
 
well, i soldered to the pins and everything, applied heatshrink, and cause im soo impatient,i touched either end of the wires to a single AAA battery, nothing happened, i even pointed it at my laptops built in webcam, which usually picks up IR, still nothing.

i am sure iv destroyed it, but it was useless anyway, still, good practise i suppose of how to solder to diode pins.
 
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Maybe the potential (1.5V AA) was too low? I thought reds and IR needed just over 2V? If the potential was too low, you may be lucky that it didnt drive the diode, because attaching it to a battery you havent limited the current! I would use a driver or PSU at a low current setting to test it :beer:
 
yh, i also just tested it with a 16340, still nothing. i dont really mind if it doesnt work, and i dont have a driver spare.
now however, i have murdered it, i wanted to push it out of the aixiz head, it wouldnt budge, so i got angry, grabbed a screwdriver, placed the screwdriver on the diode can window, and hammered it out.
to be honest, i dont really need it, i already have a red build and also some bluray diodes on the way
 
You're making my cringe. Hammer?!?!? Screwdriver?!?!?!? Dremel?!?!?!? Straight batteries?!?!?!?!

Man even if it didnt work it was a perfect practice piece. If you are going to build you need a light touch, patience, and the right tools. You have to be delicate and precise. Any single screw up and you just threw money out the window.
 
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i know, but, like i said, i wasnt really bothered about this, it seemed to be a infrared diode, and the heatsink was just a solid block of brass, and nothing would penetrate it except for my dremels grinding bit. and i only used the hammer to push the diode into the aixiz, i didnt the hammer the diode itself, but only the back of the module which i was using as a press tool. still, i havnt really wasted anything :D
 
The dremel is my favourite tool. In a skilled hand a Dremel is a tool with a surgical precision. :)
Sometimes I cleave the heatsink with the Dremel to get the diode.
Also for getting the pcb out of the C6 pill I make a incision in the edge.
 
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yep, i love my dremel, and i think it was great for this extraction, as the heatsink was about 1cm thick, so it would have taken me forever to file through it
 
yep, no worries TJ, i am familiar with how diodes work etc. like i said, i didnt relly care about this diode, cause it was probably just a IR or low powered red. if it was like a 12x, then i would obviously take the neccesary precautions
 
If you want to test it with a battery you need to limit the current otherwise the diode will just draw an amp of current or whatever the battery can supply and destroy itself.

For a small cd or DVD burner I'd stick to below 90mA so with a 4.2 volt fully charged lithium cell, from Ohms Law that would be R=E/I or R=4.2/0.09 or 46.6 ohms (47ohms would be fine).

In case you are wondering why we don't throw all our driver boards away and use resistors, if you try this with a battery that has discharged to 3.6 volts, for I=E/R you get 3.6/47=0.076 or 76mA. Thats a pretty huge variation.

Run the numbers with a high power 455nm diode that draws 2 amps and the difference between blowing the diode up and having a working laser is a fraction of an ohm. Plus you need 5 watt resistors to dissipate the heat.

I should have replied earlier but Ive had to go interstate to see my father and was in and out of airports most of yesterday.
 
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