Writing to and reading from a nano-scale crossbar memory based on memristors

TLDR

Memristor‑based crossbar memories are non‑volatile and avoid the conventional isolation devices (diodes or transistors) used in traditional memories. The study proposes a design for a nano‑scale crossbar memory that employs memristors with symmetrical, highly nonlinear current–voltage characteristics as storage elements. The architecture uses mixed‑scale crossbars with CMOS‑wire/nano‑wire intersections and one‑time configurable memristor crosspoints, along with coded demultiplexers and nonlinearity‑based write/read techniques to address the nano‑wires.

Abstract

We present a design study for a nano-scale crossbar memory system that uses memristors with symmetrical but highly nonlinear current–voltage characteristics as memory elements. The memory is non-volatile since the memristors retain their state when un-powered. In order to address the nano-wires that make up this nano-scale crossbar, we use two coded demultiplexers implemented using mixed-scale crossbars (in which CMOS-wires cross nano-wires and in which the crosspoint junctions have one-time configurable memristors). This memory system does not utilize the kind of devices (diodes or transistors) that are normally used to isolate the memory cell being written to and read from in conventional memories. Instead, special techniques are introduced to perform the writing and the reading operation reliably by taking advantage of the nonlinearity of the type of memristors used.