Safe Operating Current of Mits 635s?

[Wolfman29]

Hey everyone.

I am planning a build for a 635nm diode but I can't seem to find information as to what's "safe" for the 300mW versions.

I think I was told that 1A is generally regarded as safe for those things, but I am not sure. As for the 500mW versions... are those publicly available yet? What's a safe operating current for those?

 

[Fiddy]

hey man,

http://laserpointerforums.com/f52/rayfoss-mitsubishi-638nm-300mw-laser-diode-67381.html

 

[BIGGUN]

1100 mA to reach 500 mW?

I thought they were hitting 500-600 mW at less than 700 mA?

Kevin

 

[Solonar]

Depends on the lense used, I believe those graphs were done with an Aixiz glass lense.

 

[BIGGUN]

OK. that makes sense.

Those charts are too nice to not have spent the cash on a G-1.

:banghead: :na:

 

[Blord]

Becareful running these at 1A. Yours has already died. I would suggest 700mA. They do have a better wavelength at lower currents. You could powered the diode with an AMC7125 driver and just one 3.7 battery.

 

[Wolfman29]

Yeah, I may stick to ~700mA or so.

 

[Hemlock_Mike]

I'm running my Mitsi at 900 mA using a v5 Driver and a leftover G-1 lens.
I'm happy with 380 mW and I'm not going to turn it up like I used to do
HMike

 

[Wolfman29]

So I just did a test with an Aixiz lens, fulled screwed in as much as possible, and here were my readings:


Current (ma) Power (mW)
200 47
300 133
400 209
500 278
600 334
700 380

Efficient? Not efficient? Is it safe to run at 700mA for a while? I am not as familiar with these diodes as I am with the 445s -.-

 

[BIGGUN]

These numbers seem low..... I have to look around.

 

[Hemlock_Mike]

Wolfman --
You need to do what we did 5 years ago. Graph your data and look for a drop off in the curve. That's the cliff you don't want to exceed.
HMike

What's low? the power vs mA??? I'm now confused. When warmed up, mine hits 420 mW for a while and I've been running mine at 900 mA since I built it.

Biggun --- What readings are you getting on your laser? I'm using Scientech 362 & 365 meters. Are you saying that he may have a real good diode?

 

[Wolfman29]

Yeah, that's why I have the data. It definitely seem to start slowing down, like it was approaching the maximum of a quadratic. I would say that the maximum here would be 900mA or so... but I can't say for certain.

 

[Hemlock_Mike]

Wolf --
When I built mine, I looked at all the posted data and played safe.
I don't know what test equipment you have but you should be safe
if you have enough heat sink on the diode.
HMike

 

[Wolfman29]

Alright. Hopefully my driver doesn't flip out.

EDIT: So just did a power up with my power supply hooked up to my driver... succes! I think?

It's a bit wobbly - at ~3.8V it outputs 740mA. However, it goes between 670 and 740mA between 3.5-4.2V. Good? XD

 

[Hemlock_Mike]

OOPS --- If you're running a V5 driver, it may need heatsinking over 500 ma. Other drivers may be the same.
HMike

 

[BIGGUN]

Mike,

It seems like 400mW from 700mA is through an acrylic lens. I thought the difference between G-1 and the G-2 lenses weren't that different.

Here's the test from DTR that I was thinking of....

P10177661 - YouTube


Kevin