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help; need alternative for lm317/amc7135 based drivers

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hey there! i was planning to finally make drivers for a couple laser diodes i've collected over the years (at least for the ones i didn't break trying to hook them up to 19v 2a supply or batteries directly when i was 12 ) but i don't have any LM317 or AMC7135.
and i don't have a quick way to just order these online. but i got a lot of electronics that i hoarded over the years

so i was wondered if there were alternatives for these or just other drivers that i didn't see when looking online for ways to make laser drivers. all the ones i see are using LM317.

i don't mind if they are less efficient or a little bit less safe for the diode .

preferably ones that can handle 18650 2.5ah 3.7v batts.

btw most of the diodes are red or IR and came from DVD-CD RW drives, so im guessing most of them are 200mw (some came from drives from 2005 idk if they are less strong)

thanks for the help in advance!
 



gazer101

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LM317 is tried and true, but if you have time to experiment see what the efficiency of the AMC circuit is
 
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LM317 is tried and true, but if you have time to experiment see what the efficiency of the AMC circuit is
i know that the better way to do it is with lm317, the problem is i dont have any and no easy way to order them online, thats why im looking for an alternative even though it will probably not be as efficient. i thought about using an APL 5508 but the current output is 500mA and i dont know if a current limiting resistor will be ok to use to drop the current. i attached the datasheet of the APL5508. will it work or will it fry the diode?
 

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gazer101

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LM317's are very popular, could you not wait a week or 2 for a package to arrive?

Otherwise what you're suggesting could work, but from my limited experience I've seen that theoretically works =/=> actually works
Test it out on a dummy load and then on an actual diode, be scientific about it
 

Encap

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i know that the better way to do it is with lm317, the problem is i dont have any and no easy way to order them online, thats why im looking for an alternative even though it will probably not be as efficient. i thought about using an APL 5508 but the current output is 500mA and i dont know if a current limiting resistor will be ok to use to drop the current. i attached the datasheet of the APL5508. will it work or will it fry the diode?
The device you mention/attached is a constant voltage regulator --laser diodes need constant current drivers not constant voltage.

" i dont have any and no easy way to order them online,"??
There is no easier way than 10 pcs for less than $1 including shipping on ebay
 

hakzaw1

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Encap
just tried to PM you but I am blocked??
a minute ago the Sarah thread has been closed down??
I am glad.
It was getting creepy.
MYB an IP search showed the sender was not in London !?
hope all is good with you.
hak
 

Unown (WILD)

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Encap
just tried to PM you but I am blocked??
a minute ago the Sarah thread has been closed down??
I am glad.
It was getting creepy.
MYB an IP search showed the sender was not in London !?
hope all is good with you.
hak
Yeah I didn't get to see the rest of the thread before it got deleted. It had to be fake ... right?? I mean able to send audio directly into her ear everywhere even inside a hospital... there's no way

Edit: Oops sorry didn't mean to derail
 

Encap

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Encap
just tried to PM you but I am blocked??
a minute ago the Sarah thread has been closed down??
I am glad.
It was getting creepy.
MYB an IP search showed the sender was not in London !?
hope all is good with you.
hak
You are not blocked in my settings--don't know why a PM did not go through.
LOL Yes that Sarah thread was clever/creepy Trolling of LPF and/or real mental problems level nonsense.
I reported it--glad to see it gone as well --is not what LPF is about or meant for.
 
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hakzaw1

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yep-- I regret getting fooled.. I wonder if 'she' is a banned member.
A new one (gave no location) joined right after the deal with the two sellers with almost the same name and both in Viet Nam.. the username gave me a feeling-- seems like admin could 'vet' new members somehow.. There are other forums who do better-
My last PM to Sarah was asking for 'her' to gmail me-- hopes of seeing an IP addy that was NOT in London.
 

gazer101

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FYI it is possible to direct sound to a person using high-amplitude (super loud) ultrasound (which then emits human-hearable sound at the point of impact at the target) but that would require LOS and a really powerful speaker (which most trolls wouldn't be able to afford):
 
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The device you mention/attached is a constant voltage regulator --laser diodes need constant current drivers not constant voltage.

" i dont have any and no easy way to order them online,"??
There is no easier way than 10 pcs for less than $1 including shipping on ebay
oh, i thought the APL5508 could have worked cuz it was on the board of one of the dvd board with a resistor. too bad. (also i thought lm317 was also a voltage regulator. i guess it does more)

also the reason why i "dont have an easy way to order it online" is cuz my bank is annoying and doesnt seem to like to let their customers use their card. i get it unblocked, next day its blocked again even though i didnt use it, so its kinda hard to order online without having a way to pay online.

and i thought it would be nice to see more drivers circuits than with the LM317 (even though its better)
 

gazer101

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oh, i thought the APL5508 could have worked cuz it was on the board of one of the dvd board with a resistor. too bad. (also i thought lm317 was also a voltage regulator. i guess it does more)

also the reason why i "dont have an easy way to order it online" is cuz my bank is annoying and doesnt seem to like to let their customers use their card. i get it unblocked, next day its blocked again even though i didnt use it, so its kinda hard to order online without having a way to pay online.

and i thought it would be nice to see more drivers circuits than with the LM317 (even though its better)
Most Shoppers Drug marts sell these prepaid cards (you prepay with cash) or try Walmart if you don't have any in your area
 
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i found an LM317 while digging trough my old stuff, so i don't NEED an alternative anymore.
But im still interested in seeing more drivers designs if anybody feel like sharing ideas for alternative drivers.
(if i would like to see other drivers idea here, do i need to change the name of this post or need to make a different post since the "help" part is solved? or do i just leave this post like it is now? sorry i never been on forums so idk if thats how it works)
thanks for the help
 

icecruncher

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You need to be more specific.

"I have a lot of car parts. Can I build a car?" Is not a question that can be answered.
(I liked it). Yes you can, with one wheel and a exhaust pipe :) - will it run, probably not :)
 

BeamDump

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You can use LM324 and UC3846 - great constant current driver combination
 




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