What doing on with my 445? LED'ed diode? Dead driver? HELP!

[Jollyrajer73]

So I was using my 1.9W 445 Ehgemus last night and out of nowhere it just went to dim blue light... The area where the driver is gets really warm after a few seconds. The surface area around the diode stays cool to the touch as normal but the diode itself seems to be LED'ed though im not 100% sure that this is the case. Im afraid that the was some exposed wire inside that shorted, killing the driver or diode or BOTH! HELP! Any Ideas of whats going on?

:wtf:

:yabbem::yabbem::yabbem::yabbem::yabbem:

 

[Flaminpyro]

If you had killed the driver the led you now have wouldn't be putting out any light...
Exposed wire what the have you been watching sparkles build lasers :crackup:
There realy is no reason to have exposed wires I will give you some heatshrink
when you buy wire from me and then there is radios shack they sell hs.
So get rid of that old wire and buy a new diode and make it right !
I suspect 1.9 was too much for that diode :cryyy:

 

[Jollyrajer73]

If you had killed the driver the led you now have wouldn't be putting out any light...

Wait so do you think that there may just be a bad connection causing a short that killed the diode? Im really hoping that Ill just have to replace the diode haha

 

[Eudaimonium]

How old is the laser itself, how much runtime did it see?

If it's pushing out 1.9W after the lens, diode is being driven so damn high that it just might have caught up with it.

This is exactly why I keep all my current setups conservative. All of you pushing for 2W, this is what happens after some usage. 1W is already tremendous power. And it lasts forever on these diodes.

 

[Flaminpyro]

I think you should replace the diode and the wiring

 

[Jollyrajer73]

Well the thing is that there should be no exposed wire. DTR built this unit so I dont think that he would have used a diode that couldnt handle the power lol Its been working for months... I got it from him at the end of December. No problems until now.

 

[Flaminpyro]

Again 1.9 is a whole lot for one of these diodes it dosn't matter who built it these diodes can only take so much and then LED or zombie:lasergun:

Well the thing is that there should be no exposed wire. DTR built this unit so I dont think that he would have used a diode that couldnt handle the power lol Its been working for months... I got it from him at the end of December. No problems until now.

 

[Jollyrajer73]

I'll probably do that when I have some extra cash lol
I didnt realize that you are located so close Flaminpyro haha Makes for fast shipping time which is always a plus Do you have diodes or just wiring?

I think you should replace the diode and the wiring

 

[Flaminpyro]

I have it ALL I just need a store so you can go shopping

 

[Jollyrajer73]

I have it ALL I just need a store so you can go shopping

:crackup::crackup::crackup::crackup::crackup:
AHAHAHAHAHHAHAHAHAA!!!!!!!!! Honestly if you had a store I'd make the 4 hour drive anytime I needed something laser related! That would be great! :beer:

 

[Tech_Junkie]

So you've had a laser for months, pushing it to the edge of its limit.

I'd say you're lucky it lasted this long.

 

[Flaminpyro]

I ment on line store, there is a store here where I am at and if you make
the trip you can come in and shop till you drop then we'll go quad riding

:crackup::crackup::crackup::crackup::crackup:
AHAHAHAHAHHAHAHAHAA!!!!!!!!! Honestly if you had a store I'd make the 4 hour drive anytime I needed something laser related! That would be great! :beer:

 

[goninanbl00d]

So you've had a laser for months, pushing it to the edge of its limit.

I'd say you're lucky it lasted this long.

Exactly. The driver can't possibly be dead; if it were you'd get no output whatsoever, or erratic output, unless it failed to full power (which is very, very unlikely). At the currents involved you may damn well save on the FlexDrives and go direct drive instead. You end up blowing up the diode in any case; nobody does any long-term runtime tests at these currents.

A dead short/shorted wire/contact fault is unlikely too, that would cause no output. Besides, there isn't any torsional stress on the wires within the host (or, at least, there shouldn't be). It has no reason to come apart suddenly if it has not done so.

These diodes were spec'd (if I remember the datasheet correctly) for no more than around 700mW.

They can handle 1W fine, 1.2-1.3 would be pushing it but they can live with it.

On the flip-side, however, there's been reports of bond wires broken at 1.5A, along with COD. And at 1.9W out (that'd be in excess of 2A in), not only is the diode both at risk of bond wire failure and COD (catastrophic optical damage), it also has a TDP of close to 8W which needs to be dissipated.

Ignoring the current issue completely, you'll notice that even with direct press heatsinks, only the rim of the diode (not the can) touches the heatsink. The die itself is on a pedestal and relies solely on that little rim for cooling.

At 8W, it will get very hot, very quickly. Although the heatsink may seem cool, and gradually warm up, actual diode temperatures may be much higher.

It's a bit like the older CPUs without the IHS, the die would often be 10 to 20C above the temperature of the heatsink itself.

Now, once you factor in current, there's no surprise it did blow.

Anyone remember the PHRs? They were rated for around 95mA by the manufacturer. The enthusiast safe operating current was 110mA give or take a few. They'd last at 110mA, and they'd start dropping dead at 120mA. A few made it to 130 or 140, but not for long. Same here. 700 is fine, 1000 is a safe margin, and 1500+ is just asking for trouble. Sure, it'll last, but not for very long.

It seems that these diodes aren't nearly as fragile as the PHRs, consequently, nobody pays any attention to the fact that the risk of bondwire damage and COD still exists.

The poor diode's had a hard life. I'm still surprised it didn't go tits-up earlier. Then again, these are hardy beasts.