Go Down

Topic: arduino power concern (Read 826 times) previous topic - next topic


Hey all. I'm using an Arduino Diecimila and powering it via 4AA batteries to the VIN pin. I know that this is not ideal, but it seems to work. It has been working well this way, so far. Does the VIN pin go through the 7805? Can I expect reliable results this way, or have I just been getting lucky?

Also, I would also like to have the option of plugging the arduino in, via the barrel power jack. What happens if the arduino is receiving power from both the barrel jack and the VIN pin? Will it simply ignore the batteries, will the batteries continue to drain, or will my arduino burst into a cataclysmic  fireball?



Vin does go to the input of the regulator. It does not go through the reverse polarity diode that connects the barrel connector so make sure you always have the polarity correct. The typical 7805 regulator wants 7 volts or more and 4 AA cells produce less than this, but Some boards use a lower dropout regulator and this may be why yours works ok.

I would not use the batteries at the same time as power is connected through the barrel jack - this could damage your batteries.

Go Up