I recently ordered Sparkfun's Laser Card Module. It requiers 3V, so I can use the arduino 3.3V pin. The laser has a max current of 40mA with a suggested of 35mA, but the 3.3V pin has 50mA. Is there any way I can easily lower the current? I don't want to burn out the laser.
Current is pulled, not pushed. You could connect your laser to a 300A supply, and it would still only pull 35mA, max.
So I can hook it up to 3.3V without a problem?
yes you can.
Except that the 3.3V comes from the FTDI chip, which only provides 50ma, which only leaves a small margin for anything else to consume 3.3V alongside the laser.