well eventually I would like to use 15v at 2 amps, so that h-bridge might to be ideal for now.
To follow your idea on using MOSfet, I found a web site talking about the IRF540, which is very similar to the one I have IRFZ44N., Except they use Pmos also, I guess I can use 4 Nmos and using an inverter instead of using 2 Nmos and 2 Pmos.