A spin-transfer torque memory apparatus and self-reference read and write
assist schemes are described. One method of self-reference reading a
spin-transfer torque memory unit includes applying a first read current
through a magnetic tunnel junction data cell and forming a first bit line
read voltage and storing the first bit line read voltage. A magnetic
field is applied through the magnetic tunnel junction data cell forming a
magnetic field modified magnetic tunnel junction data cell. Then a second
read current is applied thorough the magnetic field modified magnetic
tunnel junction data cell forming a second bit line read voltage and the
bit line read voltage is stored and compared with the first bit line read
voltage to determine whether the first resistance state of the magnetic
tunnel junction data cell was a high resistance state or low resistance
state. Methods of applying a magnetic field to the MTJ and then writing
the desired resistance state are also disclosed.