arduino + 6 servos + external power supply

Forum 2005-2010 (read only) Hardware Interfacing
1

for my project I need to drive 6 servos (5V ~2Amp total). I've read that the solution to power things is as follows: get an external power supply (5V, 2A) for powering the servos. use another 9V source to power the arduino itself (battery?). and connect all the grounds.

my question: can I use the external power supply to power the arduino too in some configuration? should I get a 9V 2A power supply, connect it to the arduino external power plug, and use its 5V pin to drive the servos? or could I use the 5V 2A power supply to power the board through 5V pin?

what would be the best way?

thanks in advance,
Rubin

2

You can't draw 2A from the Arduino 5V pin. The voltage regulator on the Arduino board can only handle around 200 mA without a heatsink, and even with a heatsink it will not let you draw 2A.

3

thanks - good to know.
how about powering the arduino through its 5V pin (and GND pin) from the 5V 2A power supply ? will it work? and if so - should i be worried about frying the board somehow ?

4

Yes, you can power the Arduino from the 5V 2A supply. The fact that the power supply could supply 2A does not mean that it is going to send 2A to the Arduino. Unless you short something out, that is.