LD driver configuring questions

[dkumpula]

Running in parallel is super risky. He stated it exactly backwards. . . .

Series good parallel bad. Ok.

Doh! Thanks for the correction, Kecked, I must have been asleep when I wrote my original response. I run a couple reds in series regularly as they have low voltage requirements. Blues and greens I sometimes in parallel, but I agree that separate drivers is highly preferred. Alternatively, higher driver input voltage (assuming the driver can handle it) can alleviate the voltage issue for paired blues and greens requiring >6V peak each. The Simpledrive allows for input voltages up to 24V, so that could be an option for builders - with adequate cooling, of course.

Thanks again for the catch!

-David

[Maltes]

Where can I find the forward voltage of the diode I use?

As I understood to run several diodes in series from one driver the operating voltage + forward voltage sum of the diodes must not exceed the output voltage of the laser diode driver, but I cant find the forward voltage of the diodes I use.

PS I use Oclaro 700mW red, Mitsubushi 500mW red, NUBM07E and NDB7875, NUGM01.

[jors]

You can find all these diode specs and also ordering on DTR laser shop
https://sites.google.com/site/dtrlpf/home/diodes

[Maltes]

TY but that is the first place I looked. Dont see 'forward voltage' mentioned in the specs.
Reverse voltage is mentioned in the Oclaro 700mW and Mitsu 500mW diode spec sheets, but I don't see it in the other docs.
https://drive.google.com/file/d/0B_6...U2R2s3cFE/view
https://drive.google.com/file/d/0B_6...tYSHZLaGM/view
https://drive.google.com/file/d/0B_6...V3S1hwd2s/edit

[kecked]

2.7v @ 1.5a. Just measured it. It's also called operating voltage Vf
https://drive.google.com/file/d/0B_6...pjeWRwdHc/edit

[Maltes]

How do you measure it?

[kecked]

How do you measure it?

Have a 1 ohm resistor in series with the diode. Measure the voltage across it. Tells you the current.
v=amps. E=IR

I just measured the voltage across the diode itself. I guess you could also put the 1 ohm in parallel with the diode and measure the voltage. Since you already know the current you can back out the current in the one ohm resistor to figure the shared current in it. Now you know the current in the diode so you can call the diode voltage too. I just measured it.

[10Fenny]

Hey guys.. I was gonna make a new thread but this seems to be relivent.. so sorry if I'm derailing... I have a couple flexmods and I am starting an edison quad red build with lpc 826's. Can I run four in series? With a single flex? I do have a test load to use

[hakzaw1]

subbing....same questions...TIA TO ALL..
OP please fill out your profile..

[Maltes]

Have a 1 ohm resistor in series with the diode. Measure the voltage across it. Tells you the current.
v=amps. E=IR

No I mean how did you measure the Vf?