Maybe I can use your knowledge (I'm a mathematician :)
I'm trying to use Arduinos to form a network of masters/slaves to manage an entire Lego railroad.
Everything is OK when I use a 12v 2.5A led battery --- my circuit includes a MOSFET-P (to avoid reverse polarity issues) and a push-down converter (12v to 5v) to power the Arduino --- but when I tried to substitute the 12v battery by the Lego Transformer the Arduino works only up to the moment where I add a Lego light to the circuit, at that moment it seems that the Transformer does not have enough Amps to run both the Arduino and the light... any ideas/suggestions?
