Step 2: The driver

Picture of The driver
Sin t��tulo-1.jpg
Laser driver copia.jpg
To make a proper driver for the laser diode, etch the PCB and solder the components as shown in the diagram.

Some people only connects the LD with a resistor in series, but that driver is a better (but more expensive) way to use a laser diode.

The LM371 varies the voltage the LD uses (i cutted the top because it didnt overheat, i think i does not affect the way it works), the two 10ohm resistors in parallel set the maximum voltage and current the Laser Diode will get, the pot allows adjustment of output current, The 1N4001 diode protects the LD from a negative input as battery placed wrong, but LM317 can't deliver neative voltages, so maybe it is not necessary, and the capacitor protects laser diode  from immediate  power supply especially when switching on.

This driver is a mixture of what i have seen arround, so, if something should not go there, please tell me.
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According to my understanding of the LM317, the other end of the potentiometer should be connected to ground.

Nitroxium1 year ago
Yo,I have a lens used in laser and a really powerful bulb.Will you folks help me in making a laser outta it?
edvin19941 year ago
what size pcb need to be
pinomelean (author)  edvin19941 year ago
About an inch wide an as long as it still fitting into the battery.
If you're using anothes casing, it can be bigger.
waldosan1 year ago
the lm317 usually comes with a reverse voltage detector and safety crowbar/fuse circuit. voltage regulators in the lmxxx family are very sturdy, you literally cannot set them on fire without a torch since they have temperature safety circuits as well.