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Max volts into red diode?

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superh90x

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I am building my first project (just saying incase you haven't seen my other threads) and I got problems using 3AAA batteries and got too low of mA to the load, so I used a 9 volt, but volts across load is like 3.7, is this too high? or will it only shorten the life of my diode? I have 5 diodes btw, so if it shortens it just slightly to moderately i'll be okay as I don't plan to have this be my only laser, just enough to satisfy me while I gain experience and money for a blue laser
 





Fiddy

Fiddy

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Cant tell if a troll or not.

But your wording is really bad.

so you have 5 diodes in series?

You using a driver?
 
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superh90x

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lol, sorry, i'm tired, I have a single diode, and a driver, but after the driver the voltage is like 3.7, is that too much for a diode?
 
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superh90x

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the part about 5 diodes was to say I have spares incase I mess up, but the question was legit, I want to know if they'll fry at 3.7 volts if the current is good, or if they'll just suffer from a shortened life. if I don't make sense I apologize, where i'm at its almost 3am
 
Fiddy

Fiddy

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3.7V is too high for a red diode, red diodes like to live from 2.5 -3.0V, if your measuring 3.7V across the diode it should be dead.
 
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superh90x

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okay, so how can I get that lower? i'm running my driver with a 9 volt because 3 AAA's wasn't enough for the TTL and the diode, I was only getting 180 mA, perhaps 7.5ish volts in should solve it?
 
Fiddy

Fiddy

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what driver is it? On a good regulator, more input volts doesnt mean more current.

How are you setting the current?
 
Fiddy

Fiddy

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Dont go over 5V input!

How are you measuring the current?

Do you have a test load?
 
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superh90x

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the TTL requires 5Vin just to operate the driver, I could try again at 5Vin and not use TTL, but when I did that I got no mA out the end. i'm measuring current across the resistor in my test load using my multimeter
 
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superh90x

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may I ask if you've used a driver that had TTL before and just not used the TTL? is that possible?
 
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Fiddy

Fiddy

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Nah never used a driver with TTL.

How many diodes are you using on your test load?

have you turned the pot up an down and watched the current?
 
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superh90x

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I turned the pot and watched the current, I don't remember much, but it wasn't doing much when the positive lead wasn't connected to the TTL positive input, the driver wasn't outputting much of anything. that was before I switched to the 9volt
 
Fiddy

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try using 3 diodes, do you have a photo of how you wired it up?
 
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