NKO29
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The resistor is to set the current output of the driver. Do you have a DMM?
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- Thread starter ultimatekaiser
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I dont have one atm, i loaned it to my friend, my dad may have one though. but can someone answer my question? I think i may have wired it wrong to begin with, this is the first i've built completely from scratch. how would you wire a case positive diode with a linear lm1117?, should i just hook up anode and cathode, and cut off the photodiode anode pin, and then use the case as the positive return, with the negative going up through the center to the driver?
NKO29
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OHHHHH Case positive needs to be regulated differently then normal diodes. I think you may have directly driven the diode off the batteries, because even though you attached a driver, the diode's + is directly touching the host which is the battery's +. This is assuming you haven't isolated the diode from the case though.
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Yes! Lol i originally was going case negative.
I know what my diagnosis is. Just need a solution.
I know what my diagnosis is. Just need a solution.
NKO29
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New diode & driver from my POV. What host are u using BTW? If you cannot isolate the diode you'll need a driver that regulates the current from the negative side of the diode.
djQUAN
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100 means 10 ohms
You can regulate the current from the negative side using the LM1117. Connect the adj pin to battery negative and Vin to diode negative.
NKO29
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I was also assuming because he put the batteries into the host both ways the driver died too LOL. And like you said ---> The selected driver can regulate from the neg side 
When i see questions like this i always assume the worst, that way i can't be flamed for telling somebody to use a part of unknown condition
EDIT: ESP if the part is not of significant value. Personally if i break something i'll replace everything that i'm unsure of what condition it's in.
When i see questions like this i always assume the worst, that way i can't be flamed for telling somebody to use a part of unknown condition
EDIT: ESP if the part is not of significant value. Personally if i break something i'll replace everything that i'm unsure of what condition it's in.
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That's what I'm doing lol starting over with both new. I'll take pics as soon as I get them in. Both have shipped and should be here soon
Tmack
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Sounds like we're in the same boat. My new parts are on the way too. I used a driver of questionable quality and lost $60. First one I've killed. Still so pissed.
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That's one thing I hate about diodes. The die if you even so much as look at them wrong lol
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that sounds pretty crappy tmack! sorry to hear that.
here is the driver i'm using:
and here is the general idea of the setup i'm using so far:
here is the driver i'm using:
and here is the general idea of the setup i'm using so far:
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Bad idea!
The LM1117 is on the positive line, leaving the negative line of the driver (the ground) continuous.
In other words, your laser must be case negative. Since diode already is, just make sure to correctly wire up your battery connections - battery must be the other way as it is now.
Otherwise, with continuous negative line going through the driver board, you will be shorting out your battery via case connection (because both negative and positive lines will finally cross at the case of the diode).
The LM1117 is on the positive line, leaving the negative line of the driver (the ground) continuous.
In other words, your laser must be case negative. Since diode already is, just make sure to correctly wire up your battery connections - battery must be the other way as it is now.
Otherwise, with continuous negative line going through the driver board, you will be shorting out your battery via case connection (because both negative and positive lines will finally cross at the case of the diode).
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That's what was happening before. I was just connecting everything as was labeled on the driver. (As shown) I thought this diode was case positive?
I was just connecting everything as was labeled on the driver. (As shown) I thought this diode was case positive?
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Oh, that was "PD-", sorry, went a little too fast over the schematic.
Well, if your diode is case positive, that creates a new array of problems for you.
Long story short, you need to isolate your diode from your case connection.
Or use a different driver. Or wire up a LM1117 schematic differently, with driver assembly after the diode (looking from the positive line source) - though I never did this before, it's an idea I had but never explored. It'd be great if somebody were to chime in with some more info on this!
Well, if your diode is case positive, that creates a new array of problems for you.
Long story short, you need to isolate your diode from your case connection.
Or use a different driver. Or wire up a LM1117 schematic differently, with driver assembly after the diode (looking from the positive line source) - though I never did this before, it's an idea I had but never explored. It'd be great if somebody were to chime in with some more info on this!
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That would be fantastic, this is kind of an experiment on my part. Originally I thought it was case negative until I looked closer at the pan out and I rushed over it too fast like you did.
I wired up the laser diode negative, and the photodiode positive, which ended up working as long as it wasn't in contact with the case. Can't I just use the case as the + return?
I wired up the laser diode negative, and the photodiode positive, which ended up working as long as it wasn't in contact with the case. Can't I just use the case as the + return?
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djQUAN
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Here's one I found here in LPF by Wolfman
http://laserpointerforums.com/f40/planned-ir-handheld-build-driver-63233-2.html#post944548
http://laserpointerforums.com/f40/planned-ir-handheld-build-driver-63233-2.html#post944548
