My PHR's Keep Dying...

[Clickey]

Hey everyone, I have been inactive in the forums for a while, but every now and then, I get a sudden interest in lasers. So, as the title states, I am not very experienced with lasers, ugh honestly I never want to shell out extra money to build a more powerful laser until I can get a PHR to last more than 3 weeks. I have my circuit like this:

I used Styropyro's $3 Laser Diode Driver

So as seen in the video, he uses a 10-Ohm resistor to run 125mA to the diode. Now I did the same thing, and it eventually bit the dust...

I looked at this thread: Diodes Compilation - All Diodes Data In One Thread!
and it says that the PHR-803T's safe operating current is 90mA, and max being at 120mA. So I don't know what to do. I could using a 12-ohm resistor to run it at 100mA, which is between the safe and max, but I honestly am stuck. I don't feel like adding more PHR's to my dead diode bin.

 

[jimdt7]

Make a test load so that you can test the current.
As for the resistor just a potentiometer so that you can adjust it easilly.
Here you are: Laser Driver

 

[Clickey]

So what mA should I run the laser at, and if so how long should my duty cycles be?

 

[Ghostchrome]

100mA should be fine. Be advised that the higher current you run your diode, you are shortening it's lifetime. 90mA is recommended for a long life, 120mA is the highest you can go without instantly burning it out.

Duty cycles really depend on how well you can handle the heat produced. If you can keep the diode (and heatsink) cool, you can run it for longer.

 

[Clickey]

Alright thanks. I will let you know how it turns out. Added rep for helping me.

 

[jimdt7]

So what mA should I run the laser at, and if so how long should my duty cycles be?

Sorry for not answering but i had to go out.

If you want good runtimes run it at 100mA. It will be able to light matches.
At 125mA it will produce about 100mW and it may not last long.
I run mine at 90mA and it has lived for more that a year !
It mostly depends on the heatsink. I suggest you to buy a copper one.

Hope, i helped

Jim

 

[Kookapeli]

I'm running mine at 120mA in a Guidesman host & sink from Moh, I can run mine for a few mins at a time w/out it even getting warm

 

[bennett326]

depends if you have a phr 805t 125ma is fine if you have a phr 803t 100ma is the max

 

[Kookapeli]

It's the latter

 

[sinner]

Always go for a nice 70~80% power of the total capability.. it runs for a longer duty cycle and lives virtually forever..