Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

How to Register on LPF | LPF Donations

A little help with this

Rechargable lithium ion batteries.

Ofcourse, they'd neccesitate the use of a flashlight body to hold it all together since I didn't see any square looking, or desktop friendly lithium ions around.

But they are rechargable, last brutally long, charge in no time, excellent current capabilities.
 





I dont know what im going to use as host but i think ill just put it inside a flashlight or just a little box/case.

And yeah the V=I/R was a typo, forgot to edit it

OH and how do i short the driver? i just read that if i dont there is a chance it might die
 
Last edited:
I suggest a ceramic capacitor, they won't burn your diode if you don't short the leads before running it. They have a very low charge.


By the way: Great forum name you got there
 
Last edited:
What you probably mean is,

Shorting the output capacitor.

It's as simple as crossing the leads that are supposed to go to the diode for a second.

This is to discharge any residual charge left in the capacitor, and make it safe to connect your diode to the output.
 
You don't need an output capacitor, and it can even hurt your circuit as it'll affect your circuit as a constant current source. That diagram is very old and the idea at the time was that you'd be filtering transients at the output; however, the voltage regulator does an excellent job of rejecting problematic voltages/currents. If you put the capacitor anywhere, put it before the voltage regulator.
 
Last edited:
Eudaimonium said:
What you probably mean is,

Shorting the output capacitor.

It's as simple as crossing the leads that are supposed to go to the diode for a second.

This is to discharge any residual charge left in the capacitor, and make it safe to connect your diode to the output.
Click to expand...

exactly, thats what I meant to say, mabe english fail.

No need to do that with ceramic capacitors
 
If it's a capacitor in any way,

Yes, you need to do that. If you didn't, it wouldn't a capacitor.

But I'd go with the other advice of even ditching the capacitor altogether if it's a problem.
 
their capacitance is too small to burn a diode. I bet all my m140s, they wont burn
 
Last edited:
You can never be too careful. Better safe than buying another diode.

Besides, I've seen some really high capacitance small ceramic SMD caps, like 10uF, two in parallel was all I needed in some switching driver design for the output cap.
 
@OP What lens and module are you going to be using? And if you need more ideas on easy to build laser drivers here is a nice PDF with some (see attachment). The LM2941 driver in the PDF works great with two Li-Ions, running my lpc-826 at 510mA with 7.2V!!!
 

Attachments

Last edited:
Go to DTR's site and buy the lens that says "635nm-660nm AR Coated Three Element Glass Lens". If you are sure that the module you are using is an aixiz module then this lens will work great!
 
You must log in or register to reply here.


Back
Top