Memristor Crossbar Circuit for Ternary Content‐Addressable Memory with Fine‐Tuning Operation

Abstract

Memristor‐based ternary content‐addressable memory (TCAM) has emerged as an alternative to conventional static random‐access memory (SRAM)‐based TCAM because of its high‐density integration and zero‐static energy consumption. Herein, 0T2R TCAM operation on a 32 × 32 passive memristor crossbar circuit is experimentally verified. The effective margin, which is the difference between the match case and 1‐bit mismatch case, is improved through precise tuning operations. Moreover, the number of mismatch bits and match cases can be accurately detected thanks to the linear relationship between the number of mismatch bits and match‐line current. In addition, the nonideal effects in the passive crossbar array including dynamic voltage drop and sneak current are analyzed through SPICE studies. These results indicate that the proposed TCAM operating conditions can ensure stable TCAM operation in larger arrays.

Amorphous ITZO-Based Selector Device for Memristor Crossbar Array

“…The selector device requires a symmetric I-V nonlinearity for bipolar switching memristor, which suppresses the current flow at a low-voltage region while permitting a much greater current (about >100) in a high-voltage region [ 14 ]. Numerous researchers have scrutinized various two-terminal selector devices, which include the threshold switching device [ 14 , 15 , 16 , 17 ], 0T2M structure [ 18 ], mixed-ionic conductor device [ 19 ], multilayer tunneling device [ 14 ], and the back-to-back Schottky diode [ 20 , 21 , 22 ]. The threshold switching based on the metal-to-insulator (MIT) transition of VO 2 [ 15 ] and the fast relaxation of Ag conductive filament [ 17 ] suffer from the poor thermal stability because the VO 2 is a well-known material occurring at the MIT transition at a low temperature of 340 K [ 23 ] and the accelerated relaxation of the Ag conductive filament by high temperature.…”

Programmable Threshold Logic Implementations in a Memristor Crossbar Array

“…In response to the limitations of traditional computing architectures, computing-in-memory computing (CIM) has emerged as a promising paradigm. The memristor is one of the most promising memory devices for CIM, offering advantages such as low power consumption, rapid switching speeds, and high integration capabilities within 4F 2 crossbar arrays. − Various CIM applications can be implemented using memristor crossbar array structures, including a neuromorphic system, − physical unclonable function, − content-addressable memory, − and digital logic gate. − …”