external alimentation 5V / 5A

Hi folks,

I 'found' an toshiba power supply (5 V / 5A) (regulated?) and I want to know if it is ok to use it with a duemilanove.

I need an external power supply to run 5 or 6 servos.

Thanks for any advices

Sounds like it would be fine, but your statement included " (regulated?) " which should be determinded.

Most hobby servos will work on DC values from 4.5-6vdc. However your Arduino cannot be consider safe if the voltage is ever much higher then 5.5vdc. You should be able to test the supply by wiring varying resistance loads to determine if it indeed a regulated supply that supplies a constant voltage from zero amps up to it's rated capacity. It most likely is regulated but worth checking out.


hi retrolefty,

here is the model number, may it help you to help me to figure out if the power supply is 5V regulated :


thanks again


Yes, that would be a regulated supply...

@westfw & retrolefty

thank you very much for your advices.
But, I have an other question related to this topic. Should I plug the power supply directly to the arduino's jack or to the 5V chanel ?


Should I plug the power supply directly to the arduino's jack or to the 5V chanel ?

If you mean the Arduino external power jack, that won't work as that power jack requires a voltage of around 7.5 to 12VDC, +5vdc won't work there. You can wire it to the Arduino +5vdc and ground pins, as many do, but that is not my favorite way for several reasons. My favorite way is to take a spare usb cable and hack off the computer end and find the +5vdc and ground wires and wire that to your power supply, that way you can just plug into the Arduino USB connector and you are good to go. If and when you need to upload a new sketch you just unplug your power supply and plug in your computers usb cable and that will then power the board during uploading.

Keep in mind that your external loads requiring +5vdc (like your servos) should have their own seperate power and ground wires from your new power supply and not try and use the +5vdc and ground wire pins on the Arduino shield connector to supply your external loads.