lapompo said:
Thanks for the answer =)
ye was as an comfirmation about the things I found would work
So change the Capacitor I found first with 65-229-08 and one of the pots you showed and its spot on? =)
Well, no. You'll have to decide on the current you'll want to use. This depends on the LD you'll be using and how much power or life you want from it. The resistor determines the maximum current you'll be getting, and the pot determines how much can you adjust the current. There is a xls-sheet for calculating the resistor/pot values, try searching ddlrescalculator_kendon_xls_001.zip
And about the capacitor, that must be the most expensive model they have, or something, over 7 euros!? Try 67-008-27 instead. In capacitors, you'll need enough capacitance (people have been using values from 10uF to abt. 47uf). At least one picture in this thread marks the capacitor as 10mF, which really is 10000uF, that'll be an overkill
So, to sum up:
Regulator LM317, there are some small variations, like LM317H, which can only handle 500mA, but if you do not have any special needs, take the LM317.
Diode 1N400X, so 1N4001 through 1N4005 will do, to my knowledge, the only difference between these is the voltage handling capability.
Capacitor, electrolytic versions will do and tantalum as well, these are the most used in this build, voltage rating preferably twice the voltage you'll be powering the circuit with and capacitance about 10uF-47uF.
Resistor and pot. 50ohm pot is good, 20ohm maybe even better, depending on the currents you'll want to use. The smaller the maximum resistance, the easier it is to adjust the current accurately. Power rating must be sufficient, 1,5W is enough for most applications, 0,5W may be enough for violet lasers. Same goes for the resistors. The values are up to you, use the chart or search the thread for calculating it for yourself. The total resistance, which is pot+resistor range typically from about 3 ohms in high power applications to 30 ohms for lower power use.
And while you're at elfa, or ordering from them, get a bunch of the 1N400X-diodes, they're cheap and can be used for making a
test load to test your completed circuit on. And get a resistor with a resistance of 1ohm and power rating of at least 1W and you can build the test load. Search for DDL_circuit_test01_001.jpg, this shows the schematic with a test load for setting the current and checking the voltage.
And remember to short the output of the circuit for several seconds after you've tested it with the test load, without the batteries connected of course, before connecting the laser diode. Otherwise you'll kill the LD.
It will be more difficult..so be careful.
