Nondestructive Read Circuit for Memristor-Based Memories

Abstract

Background: Memristor is a two-terminal passive nanodevice whose resistance (conductance) is a function of the past current flow. It is nonvolatile in nature and stores the binary data in the form of resistance. Its compatibility with the existing CMOS memory peripherals makes it interesting in the field of memory design. High density memories are realizable with the use of multilevel crossbar array of memristors. To write data into the memristor are as simple as to apply a DC bias. But reading in a similar trend would yield the loss of data. Various solutions based on AC bias, etc., have been proposed earlier. Methods/Statistical analysis: This paper explains a nondestructive read circuit which does not require an AC bias scheme. The proposed technique uses memristor as a feedback element in the noninverting operational amplifier. Hence, the resistance of the element is not much affected due to read operation. This makes the circuit more stable and nondestructive read operation. Findings: As the proposed circuit reads the content of the memristor memory without disturbing the content of the cell, it avoids refreshing or restoration of the memristor content after each read operation. By that, it improves the speed of the memory access and reduces the power dissipated. Application/Improvements: As the memristor memories support multilevel data storage, the proposed circuit can be modified to perform nondestructive read the content of multilevel memristor memories.