The present disclosure relates to memory arrays with read reference
voltage cells. In particular the present disclosure relates to variable
resistive memory cell apparatus and arrays that include a high resistance
state reference memory cell and a low resistance state reference memory
cell that provides a reliable average reference voltage on chip to
compare to a read voltage of a selected memory cell and determine if the
selected memory cell is in the high resistance state or low resistance
state. These memory arrays are particularly suitable for use with
spin-transfer torque memory cells and resolves many systematic issues
related to generation of a reliable reference voltage.