Fried 2 blue diodes.... ^&@^&#^&#&*@&*!!!!

[hobbybob]

Tonight i tried to build another blue module.
After having built my greens into green blues it seemed like a simple task.
I used the quaddrive from Badpip , really cool design with beam suppression.
Adjusted the driver with 5volt as instructed, adjusted bias to 200mA with beamsuppresion jumpers off.
Then applied 5 volt also to the modulation input and adjusted gain to 1050mA.
I then shut down everything, connected diode. Just very faint. turned off whole thing. took beamsuppresion jumper off.
Turned it on, ok very faint and when applying 5V i got some output but still not much.
Then i thought ok, maybe the 5 volt can't power the thing.
Connected a 12V supply to power the driver, 5V to the mod input. Same thing.

Thought ok, then i must've killed the diodes with static electricity (which seems weird, since i just soldered the 2 wires on , didn't touch it afterwards. Have touched the diodes in the green/'blues a lot more..but ok).
Ok, maybe the channel is acting up, i got 4 channels so lets try another channel. Wired the whole thing up. Adjusted it again with 5 volt. Then switched to 12v to power the whole thing, 5v to mod input.
Lets see how this go.. Aaah yeah finally bright light i thought... for 0.5seconds and then it died to.... BANG...another one blue gone.... NOOOOOOOOOOOOO!
It fucking just blew up on me and died on the spot. Grrrr..... what the fuck.... now i have 2 blue LEDs.

I disconnected diode and checked the power again with an amp meter attached.
204mA in bias, 1058mA when 5v was applied to mod input.... I remember putting 1.15A (1150mA ) through the one i build in the UK during the LEM.

Damn, i am so disappointed. I have only one blue diode left. I could try and set it to 500mA max. and 200mA bias.
But if it just puts through a lot of current on startup it will fry this one as well.
But i don't understand it. I must have done something wrong, but all the numbers seem ok.
It seemed like it put all the current through at once, while in test with the amp meter connected it showed the right numbers... Damn... i am already busy for 6 hours now, how hard can it be ?
I'd hoped just to finish the module tonight. I am so angry i can throw the damn thing out of the window. So i won't be soldering tonight anymore.

Please, ANY help is welcome, i followed the setup instructions to the letter, i build several blue modules myself with succes , right on the first or second try.

[dilbert]

Dimitri, I have an idea what happened - am away on iphone till tmrw night, will pm you when i get back to PC.

[hobbybob]

Huh? Ok, cool... hope you can help, i will wait for your (and others if anyone has ideas) suggestions.
I am completely out of options and blank now. Will not touch a soldering iron now, as i am so mad i will only hurt myself ;-)

Will watch an episode of The Big Bang theory. Just to see other nerds fuck up their lives too...

Thanks for your reply Dilbert. Remember this is another driver as the one we used at the last LEM!

[liteglow]

I did blow 2 diodes at one week

The first one I forgot that the Driver was 3.volt (pen-light style) and added 12volt ..ohhps
The other one was working great on the flexmod.
But it was a tight fit into the LAB-style housing, so I pushed it to hard and after that no light :P


I`m glad I did buy 4 of them.
think I need 4 more

[steve-o]

Sorry for your loss 2 more in LD Heaven . RIP. If it's any consolation I blew 3 opnext 635s in the last 2 months forgetting to reset the current, bad reflow solder joints during experimentation etc.. . $375 out the window . This i$ a damn expensive hobby. But at least I don't have to buy golf clubs. I've heard they're really expensive. A helluva lot more than laser diodes. That always makes me feel better. .. There are a lot more expensive hobbies than this. I'm sure that you'll get it all sorted out and have a great blue in the end.

[no-esc]

Did you short the leads on the driver after setting the current and turning off the driver before connecting the diode?

[hobbybob]

This afternoon i went to Edison.
I redid every step i took on a new driver. That worked.
Then we redid every step on the driver i used. That worked too ?!?!?!?
I seriously don't know what happened.

Badpip's driver worked like a charm. We didn't blow up any more diodes.
Some numbers:
Running on 5V Badpips driver was able to drive the 1W blue to around 850-900mW
Then i could turn and turn but the output didn't go up.
On 12V it reached easily 1170mW but i thought that was a bit too much, so we dialed it back.
After placing the prism pairs we got a nice 980mW out ;-)
The driver was then drawing 930mA on the 12V side.
The block where the blue diode was mounted in reached a temperature of 24.2 degrees celsius after 15min running of full power.
The hottest spot on the cooling block was then measuring 49 degrees (but on the side it was only 32 and on the other side of the cooling block it was only 24 degrees). So basically the coolingblock got hotter than the diode ;-)

Well anyway some nice info i'd like to share with you! So for people building a blue but only having 5V. No problem if you don't need more than 800-900mW.
And remember, the driver has got 4 channels so running 3 reds and one blue is also no problem, since the reds have a lower Vforward, you can run both blue and red from 5 volt. Some greens also run on 5V, so if need be you can build a projector using only 5V for the modules/drivers and then 1 additional 15/24V for your scanners. Cool huh ?

Well thanks everyone for their help and support. But especially Johan for helping me out tremendously. Thanks Edison, you rock !

[badger1666]

hey dimitri
your first report promted me to set up my badip driver
and test it on a couple of loc's i have lying around ,and you do need to ground the output after setup,
or it will pop diodes,as i found out, but other than that, it a most excellent driver, just wish it had monitor pins so you could set it up
with the diode in place,(like on the die4drive), looking forward to using it in my next winter build

[Badpip]

Hi Dimitri,

I'm glad you got it working in the end, and thanks for the test data.

I knew 5V would be enough to power a blue, but I didn't expect it to deliver that much power - maybe a couple of hundreds mW, but 900? That's really great

This means that a 5V supply adjusted up to 5.5V will be enough to give full output

hey dimitri
your first report promted me to set up my badip driver
and test it on a couple of loc's i have lying around ,and you do need to ground the output after setup,
or it will pop diodes,as i found out, but other than that, it a most excellent driver, just wish it had monitor pins so you could set it up
with the diode in place,(like on the die4drive), looking forward to using it in my next winter build

Thanks for the feedback, suggestions are always more than welcome

Shorting the outputs is always a good idea, I'll rewrite the manual to make this more clear.

As for monitor pins, these can be easily added, I'll put them on the next revision

/Thomas

[badger1666]

@badip
let me know when the next revision is out then,
and i will buy one,