I have a 12v LiPo battery, arduino mega and two 6v dc motors (which will be powered by a motor shield). Although arduino can be powered using 12v, i don't want to do it because a lot of power will be wasted as heat by the regulator. Is there any way I can provide 6v (or 7v) to the board without using linear regulators? And switched regulator circuits look too complex for me.
Also I'm planning to give 12v to the motors, but use a low maximum value (150 instead of 255) in PWM to keep them from heating. Is this a good idea?