# Maximum amps that I can supply the Arduino one?

Hi, I have a transformer 18.5V, 3.5A, if I put that up?, it burns. arduino One? Maximum amps that can provide the arduino one?

If you mean can you use the 18.5 supply to power the Arduino. Do Not! Use 7, 9 or 12 volts. 7VDC @1 amp is best.

http://arduino.cc/en/Main/arduinoBoardUno

18.5 V is not recommended but is below the absolute limit of 20 V.

The Arduino will only draw the current it needs. If you supply it with 7V you can draw about 1A through the regulator.

Unfortunately at 18.5 V the regulator will have to dissipate almost seven times as much heat (dropping 13.5 V instead of 2 V). The Arduino alone should be OK (it draws less than 100 mA) but if you hang a bunch of LEDs on the output pins or devices on the 5V pin, you might find that the regulator burns up.

Naruto128:
Hi, I have a transformer 18.5V, 3.5A, if I put that up?, it burns. arduino One?
Maximum amps that can provide the arduino one?

As others have said, it is not the current that the power supply can supply that matters, it is the voltage. The fact that the power supply can provide 3.5A makes no difference, the Arduino will only use as much current as it requires, but too high a voltage will cause problems.

Another thought. Does this â€˜transformerâ€™ provide alternating or direct current ? If it is alternating them do not connect it to the Arduino.

UKHeliBob:

Naruto128: Hi, I have a transformer 18.5V, 3.5A, if I put that up?, it burns. arduino One? Maximum amps that can provide the arduino one?

As others have said, it is not the current that the power supply can supply that matters, it is the voltage. The fact that the power supply can provide 3.5A makes no difference, the Arduino will only use as much current as it requires, but too high a voltage will cause problems.

Another thought. Does this 'transformer' provide alternating or direct current ? If it is alternating them do not connect it to the Arduino.

This transformer provides DC I can then use a transformer 9v, 3.5A?

Yes.