A Variation-Tolerant, Sneak-Current-Compensated Readout Scheme for Cross-Point Memory Based on Two-Port Sensing Technique

A variation-tolerant and sneak-current-free readout technique for cross-point non-volatile memory is presented. The proposed readout circuit has a sneak current compensation port, which collects sneak current information from multiple unselected cells, and efficiently cancels it out without delay and area overhead. In addition, this scheme averages out the random mismatches in the unselected cells so that the variation in sneak current does not affect the random read-current distribution. The proposed technique is verified using a generic device model, and the results show that the sneak current is completely compensated without sacrificing variation of the sensing current.