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FrozenGate by Avery

40mW Sanyo 635nm LDs on Ebay

Ok I think you're right. If I'm reading the data sheet right pin 1 is LD - pin 2 is either LD + or PD- (common) and pin 3 is LD/PD + so it would have to be isolated from a case negative host. Those diodes are opposite of the Samsung 635s I bought from modwerx which I've never seen in a red before. I was under the impression that all reds were case negative.

I'm not sure how the hell you'd wire one of those into a pen host. You could isolate the module with that special thin tape that DX sells or maybe even just a piece of paper but I have no idea how you'd get ground. I guess you could sandwich like 1/4" of some fine, thin stranded wire like what flamingpyro sells between the host and the insulation and run that to LD-. it's so fine it'd fan out and not be very thick but there's very little room between the module and host.

I'm going to shut up now because I don't want to be responsible for ruining someone's $20 diode. You may want to post a thread asking some of the more knowledgeable people here to verify the pin out and how to wire that diode without frying it because I've never seen a case positive diode before.
 





Cool. Good luck with the build. I look forward to seeing your completed build. I'm tempted to snag one of those diodes before they're gone.
 
Well, almost all green lasers have case-positive pump diodes, so look for inspiration there if you have to. Ideally you should rig a host where the batteries are inserted the wrong way around, with their positive to the casing.

Besides that, there are also switchmode regulators that invert voltage, which coudl prove useful if you want normal battery combination combined with a case-positive diode.
 
Remember that these can most likely be pushed to ~80mW.

At least we drive all other common diodes at around 2x the rated CW output..
 
I spent a lot of time thinking about isolation but everything seemed messy so I put a little thought into it and then lab tested my idea. Check it out a low side current source now I can make it case positive and use the +LD pin as the + battery pin. :) What do you think?
IDiode = 1.25/R Note the TO-220 and TO-92 packages have different pin outs

lowside.jpg
 
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Blord said:
I suggest you try with a little cheaper red diodes. Those from a old 8x-16x DVD-burners are excellent for building exercise. And you learn also how to breakdown the burners. Very educational.

These 40mW 635nm are more expensive. You should work on them when you have confident in succes.
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Thanks for the suggestion, Blord. I'll keep an eye out for those. I probably won't get a chance to try a build for a few months anyway. Things have been sort of chaotic in our household recently and I barely have time to sit at the computer to try to keep up with the forum as it is, let alone do any electronic tinkering. I haven't even fired a laser for a few weeks now, except to verify that they work, even though I have a couple of new ones. :cryyy:

Ed
 
Grix said:
Remember that these can most likely be pushed to ~80mW.

At least we drive all other common diodes at around 2x the rated CW output..
Click to expand...

The data sheet seems to indicate it will do 40mw at 100ma and it can be pushed to 140ma. Personally I will be running at approx 110ma with my LM337 Driver and 2x 10440 batteries.
 
midias said:
The data sheet seems to indicate it will do 40mw at 100ma and it can be pushed to 140ma. Personally I will be running at approx 110ma with my LM337 Driver and 2x 10440 batteries.
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The LOC's data sheet also says rated 200mA, but we usually run them at 300-500mA :)
 
Good luck. If it runs well on 150-180mA, I planned it to install on the dead Sentorch.
 
I was reading about this yesterday and decided to wait....but then snuck in today a grabbed the last one for $20 :na:

Should be a cool little pointer!

Grix said:
I plan to run mine at around 150mA, I'll raise it to 170-180 if it goes well. I'll let you guys know.
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Please let us know! Im still unsure what I want to run mine at.
 
Got mine today very nice package. I have also powered it on and my lowside driver works perfect. Now you can make it into a pen because LD+ and batt+ are the same :)

Just a reminder this is what I did. I used a 12.1 ohm resistor for R and the current through the diode is 1.25/R

Also it produces about 46mw at about 104ma

lowside.jpg
 
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