An Offset Readout Current Sensing Scheme for One-Resistor RRAM-Based Cross-Point Array

The uneven sneak-path currents in resistive random access memory (RRAM) severely constrain the array size. To overcome this issue, we propose an innovative readout scheme that can fully offset the sneak-path currents in one-resistor (1R) RRAM array. Furthermore, the bit cell resistance (Rcell) in an RRAM array can be simply evaluated as the ratio of read voltage (Vread) to the sensed offset current (Ioffset). Even under extreme device distribution, a 512×512 array size is still obtained. This is the largest array among simple 1R RRAM, without using a selector device or extra transistor.