need help finding right voltage regulator

im looking into making a driver/controller circuit for some TECs i got. the data sheet info for the TECs is included below but im looking for a (very)low dropout voltage regulator that i can make into an adjustable circuit.

8.5A seems ridiculously high to me... What are you trying to cool?

LM317 regulators work just as well powering TECs as they do laser diodes. You'll never see those TECs draw anywhere near 8.5 A of current while using them to cool lasers. A heatsinked LM317 should work great.

EDIT: I should have said "while using TECs to cool low/medium powered lasers"..

ElektroFreak said:

LM317 regulators work just as well powering TECs as they do laser diodes.

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Yes they do. They don't however, handle 8.5 amps very well, nor are they particularly low dropout. The 1117T has a volt lower dropout than a 317T, though again, 8.5 amps is enough to power a toaster oven, you'd need some sort of very large and meaty regulator for those currents.

I'm leaning towards maybe that's a typo? Otherwise you got this TEC out of a mini fridge or something, in which case you can try vastly underdriving it with any regular driver we normally use for lasers.

pseudolobster said:

[quote author=ElektroFreak link=1229174371/0#2 date=1229196373]LM317 regulators work just as well powering TECs as they do laser diodes.

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Yes they do. They don't however, handle 8.5 amps very well, nor are they particularly low dropout. The 1117T has a volt lower dropout than a 317T, though again, 8.5 amps is enough to power a toaster oven, you'd need some sort of very large and meaty regulator for those currents.

I'm leaning towards maybe that's a typo? Otherwise you got this TEC out of a mini fridge or something, in which case you can try vastly underdriving it with any regular driver we normally use for lasers.[/quote]
Be closer to 0.85A to cool a laser diode........the thermal load is fairly minimal.

i did find a regulator last night that powers up to 3a but i just woke up and i cant find it anymore. :-X im not looking to push the whole 8-9a of power thru it. i got a sink i want to cool for a laser. the peltier itself is only 5/8" so if it did come from a mini fridge they were prolly using a lot of them. i thought about using lm317 circuit but the voltage needed to run it would be too high. im looking to run the whole thing(laser,motor,tecs) off a 3v 2a power supply. the tecs draw all the current when hooked up with anything else so i need a driver to use for that.

ok well heres my second ? since you answered my first... : i know with the lava drive and 3.6vbatts(lavadrive v3) that the driver goes up to ~700ma but since im not powering these off batteries could i use the same 3v 2a power supply and still get the same ~700ma range?

pseudolobster said:

you can try vastly underdriving it with any regular driver we normally use for lasers.

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ive tried underdriving them with a lavadrive and with a ddl style driver pushed up over an amp and it doesnt even touch it yet. you guys have any other suggestions for driving these or should i just sell these and buy more. i only bought these b/c they were so small(5/8").

Please post a picture of your practical construction. If its built well, the TEC should have your laser freezing with no more than a few watts of electrical power.

there is no construction yet. i cant build anything til i find some way to drive the TEC. so far the best power supply ive used for them was 1.5-3v(1-2 aa batts). ive ordered some 3v 2a dc wall adapters and was gonna try them but theyre coming from china so i might not even get them for another week or 2. atthe moment i just have a peice of aluminum bar  thermal epoxied on each side to act as a spreader(mostly to spread heat from hot side) b/c i already ruined 1 of them b/c it got too hot and the ceramic plate slipped off the solder joints.

not sure if it will help but heres the whole data sheet for these specific TEC's(had to host it elsewhere): http://www.mediafire.com/?sharekey=672dcbbf957df7d2d2db6fb9a8902bda