A magnetoresistive device is provided with separate read and write
architecture. In one embodiment, a magnetic tunnel junction (MTJ) has a
nonmagnetic nonconductive barrier layer sandwiched between two
ferromagnetic conducting layers. A first read line is coupled to a first
ferromagnetic layer and a second read line is coupled to a second
ferromagnetic layer such that a voltage difference between the two read
lines will produce a current flowing perpendicularly through each layer
of the MTJ. A first write line is separated from the first read line by a
first insulator and a second write line is separated from the second read
line by a second insulator.