For those interested in pushing the LPC-826 hard, I set up a test.
Conditions:
- 4 x LPC-826 mounted in Dave's brass mounts, 660AR lens.
- All mounted to a common 8mm ali block, TEC cooled @ 25c.
- Flexmod P3 with 4 x 1 ohm series resistors.
- All diodes measured within a few millamps drive current @600mA.
- All diodes measured 322mW +/-2mW.
- Test run CW for 816 hours (34 days).
Results:
- 1 diode going strong @ 320mW
- 3 diodes all LED @ <20mW
Conclusion:
While the LPC-826 appears to be slightly more efficient and also handle more drive current compared to the LPC-815, it would appear they are not able to cope with prolonged output at the top of the curve. All diodes still measure the same V drop and current draw, so the failures must be optical.
This space for rent.
Very nice test you got there; so we will stick with the 500mA limit to keep em happy and healthy for a bit?
I think so. I am heading out to pickup a few more metric machine head bolts etc. when I return I will replace the diodes and start another test at 500mA. I am keen to find a reliable CW power for these diodes while pushing them >420mA.
I do not want to suffer failures once this red laby is in my completed projector!
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Hi all
Im running two Lpc826 on my PJ, alias Lunch Box, 3 hours daily. 45 days now, and running good (aprox 500mW) after cube.
No TEC, Daves mounts, on Alu plate 10mmX150mmX60mm,
At 510mA and with O-like lenses.(in series) Flexmod 2 , and 12 Volts PSU.
Just mis dos centavos.
Cheers,
Ed
BTW Now here is hot, more than 33 degrees
Hey Wayne... running tests for a four banger?
I don't know.. but it looks like you may be taking a lot of loss on your lensing there. 320mW @ 600mA appears to have approximately 20% loss. That loss has to go somewhere, partially as back reflection and therefore possibly leading to a quicker optical death. That’s approximately 70-80mW of lost power and an unhealthy portion of that may be reflected back onto the die.
Those reds don’t really like that.
Just a thought.
A couple of deg. cooler may also help. (20°)
Cheers...
hey frank, if i remember correctly, wayne does not use optima lenses as he doesn't have any yet, so he goes with aixiz grade lossy - clipping glass lenses. that could yield the 20% loss
"its called character briggs..."
Yeah that test was with lossy lens.
I have since been graced with G2 lens from Dave, also a set of 660nm Dielectric mirrors. My quad is now doing 1270mW with 4 x LPC-826 @ 500mA. I think that's about as good as it gets. Looking at this Quad now, I will call it "Dave-660" as the LD mounts, micro flexure mounts, lens, lens retainers and mirrors have all been provided by Dave!
Photos here: http://www.photonlexicon.com/forums/...927#post192927
Last edited by dnar; 05-26-2011 at 17:44.
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is there any way i could get these friggin diodes?? (and not pay 13usd a piece for them??)
i start to get jealous of these builds and my 815 diodes start to look dim and pale...
"its called character briggs..."
After reviewing this thread it looks like the 826 diodes are a little better (10%) than the 815s. And all other things being equal I would prefer them, however I can get dozens of the 815s for between $5-$10 US whenever I want them. What is the cost of the 826 and why such pain and suffering in getting them?