A closed flux magnetic memory cell has a ferromagnetic pinned structure and a
ferromagnetic
free structure. Data is stored by controlling the relative magnetization between
the pinned and free structures. The free structure is formed as a horizontally
extending toroid, or tube, that is insulated from the pinned structure. A first
conductive line passes through the center of the free structure while a second
conductive line is connected to the pinned structure. A third conductive line can
be formed through the free structure. This line is insulated from the toroid and
the first conductor. The third conductive line can also be located outside the
free structure. In operation of one embodiment, the first and third conductive
lines are used to control the magnetized direction of the free structure. A resistance
between the first and second conductive lines defines the data stored in the memory cell.
