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on closer insspection, the TPS61200 has a 500mv feedback voltage, this is low enough to allow current regulation without any extra chips. simple! this chip would make an awesome laser driver. it could run off a single cell ni-mh. turns out i actually ordered one a couple of years ago, but...

it is totally possible to set this chip up for constant current using an external op-amp. its been discussed in other threads and in my 2xAA blueray driver thread, the last design i drew up (but never made) would work with any smps chip, just change resistors to get the right feedback voltage...

so its a nitrogen gas laser :) awesome, i am going to make one when i have some free time... and 5KV

looks like a voltage booster, you should be able to run a laser off it using a resistor, but no guarantees on stability longevity etc... also you might be getting some serious spikes from the booster that an led could take, but will kill a laser, so throw some capacitors on to smooth it out. if...

lol yeah i was actually. but then i got bored and decided to check LPF

i suppose you could use it for a red. but you would need to make sure that the input voltage is lower than the voltage accross the LD. so it should work off 2*AA's. probably a good idea to have a zener diode to protect from too high voltages the schematic for the first one is in the datasheet...

if you have a ps3 sled, you could use the linear lens servo (stepper motor) out of that and put your concave lens on it. someone would probably have a few they can sell you. maybe ask daedel or you could have some sort of threaded barrel

i used the objective lens out of a 115 the lens in the blueray is actually part frensel for a shorter focus point. so it leaves rings in the beam. i think the 115 lens is also part frensel but the lines are only around the outside of the lens. i don't think it would be much good for pointing...

ok then, you don't need to bother with the opamp or anything. just look at the first page for circuit layouts. if you want you can make one yourself... otherwise you will have to wait a bit. how many do you want anyway?

uhh. do you guys want them for bluerays or hd-dvd lasers? (hd-dvd's don't have the (-) pin connected to the case) and if you want them for bluerays, do you plan on grounding the body of the laser? I have uni exams coming up, so i won't have time to make any for like a month also i don't have...

as far as i know (although i am not an expert on lasers) the main limitation you will face will be the lasing cavities not being able to handle that much light... so cooling it to -40C will not really change that. you would probably get just as much power running the pelter at 2W as at 200W...

basically that regulator works by changing the 'out' pin untill there is 1.25v between the out and adj pins. so for constant voltage mode it uses a voltage divider to divide the output voltage to get 1.25v between the out and adj pins. so its constant voltage. for constant current, you use what...

i reckon the current is probably drifting as the led heats up. because you have it set as constant voltage right? you should set it up as constant current, it should be exactly the same as using an lm317 as a constant current source (i think) what input voltage have you got running it? and what...

thats ok. everyone has mental blanks every now and then. especially after a big night ;D

sorry but i don't see the short. if you remove the capacitor, you would remove the wires to the cap as well, not just short them together

WHAT? um whats the problem? it looks pretty standard to me the input capacitor is to smooth any ripples from the power supply, it only conducts when there is a change in voltage, for DC, it will not short the input

so what is an ampoule? wikipedia didn't return any sane answers http://en.wikipedia.org/wiki/Ampoule or are you talking about those little smd inductors

the shunt and tantalums are still ok, they always looked like that :-/ thats a good idea. i will do that next time i make one. what did you use as a fuse? and yeah the small cap is a good idea, i didn't want to risk it. btw the laser diode still works :D

If anyone makes one of these, remember to have reverse polarity protection on the driver. :-[

ok i take back what i said about the optics being useless, i just tried using the objective lens (the one mounted on a servo with magnets and coils) and it works really good, parallel beam width is less than 1mm... (awesome) i mounted it in an aixiz module what you could do, is reuse the servo...