A memory unit includes a giant magnetoresistance cell electrically coupled
between a write bit line and a write source line and a magnetic tunnel
junction data cell electrically coupled between a read bit line and a
read source line. A write current passing through the giant
magnetoresistance cell switches the giant magnetoresistance cell between
a high resistance state and a low resistance state. The magnetic tunnel
junction data cell is configured to switch between a high resistance
state and a low resistance state by magnetostatic coupling with the giant
magnetoresistance cell. The magnetic tunnel junction data cell is read by
a read current passing though the magnetic tunnel junction data cell.