:)Could anyone tell me if it's necessary to use diodes for kickback protection when using servos with an Arduino? If the servos are powered externally is there a danger for the output pins? I understand for dc motors and solenoids it's necessary but see no info on this as regards to servos :-?!! Thanks, Goatboy
It is not necessary to protect Arduino pins driving hobby servos. The servo has the equivalent to an H-Bridge and the Arduino output is not driving the servo motor directly.
Some servos require considerable current, perhaps more than an Arduino regulator or USB can provide, also servos can generate noise spikes so decoupling and external power supplies may be needed. Grumpy_mike has some tutorials on these if you want the details: Tutorials
FanBleedinTastic ;D