Flux-controlled Memristor Emulator Research Articles

Tunable memristor employing only four transistors

This paper introduces a flux-controlled memristor emulator circuit which can be controlled by electronically both fix and variable parts of memristance. Here, the fix part symbolizes the average memristance value, and the variable part refers to the changing part around the fixed part. Another advantage of the presented circuit is that it is composed of only four transistors and one grounded capacitor which provides memory to the circuit. For this reason, it can be said that the circuit is very simple, compatible with both VLSI implementation, and suitable for implementation on breadboards using discrete circuit elements. The proposed circuit can be operated at MHz frequency ranges and a strong pinched hysteresis loop can be seen at these frequencies. Finally, all simulation and experimental results are compatible with previous studies.

Electronically Tunable Memristor Emulator Implemented Using a Single Active Element and Its Application in Adaptive Learning.

In recent times, much-coveted memristor emulators have found their use in a variety of applications such as neuromorphic computing, analog computations, signal processing, etc. Thus, a 100 MHz flux-controlled memristor emulator is proposed in this research brief. The proposed memristor emulator is designed using a single differential voltage current conveyor (DVCC), three PMOS transistors, and one capacitor. Among three PMOS transistors, two transistors are used to implement an active resistor, and one transistor is used as the multiplier required for the necessary memristive behaviors. Through simple adjustment of the switch, the proposed emulator can be operated in incremental as well as decremental configurations. The simulations are performed using a 180 nm technology node to validate the proposed design and are experimentally verified using AD844AN and CD4007 ICs. The memristor states of the proposed emulator are perfectly retained even in the absence of external stimuli, thereby ascertaining the non-volatility behavior. The robustness of the design is further analyzed using the PVT and Monte Carlo simulations, which suggest that the circuit operation is not hindered by the mismatch and process variations. A simple neuromorphic adaptive learning circuit based on the proposed memristor is also designed as an application.

Electronically Tunable Flux-Controlled Resistorless Memristor Emulator

This article demonstrates a voltage differencing inverting buffered amplifier (VDIBA)-based resistorless flux-controlled memristor emulator circuit with tunability. Two VDIBA blocks serve as active components, and a grounded capacitor serving as a passive part. The proposed emulator design is devoid of multipliers and resistors through effective utilization of port relationships. Including tunability, the suggested emulator functions in both incremental and decremental modes. It accurately depicts the attributes of an ideal memristor up to 12.7 MHz and consumes a total power of 1.34 mW. The mathematical analysis is substantiated through Cadence simulation in 0.18- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> m Taiwan Semiconductor Manufacturing Company (TSMC) technology with the supply voltage of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pm$</tex-math> </inline-formula> 1 V. Nonideal, single/parallel, Monte-Carlo sampling and corner analysis were conducted to confirm circuit resilience. The nonvolatile nature of the presented emulator model has also been included. A breadboard prototype incorporating the ICs CA3080 and LT1193 are built to conduct an experimental demonstration. The experimental findings were consistent with the theoretical expectations and simulation results.

Flux-Controlled Memristor Emulator and Its Experimental Results

A flux-controlled memristor emulator built with off-the-shelf electronic devices and based on a TiO2 model is presented in this article. The circuit proposed in this article uses the current mode approach based analog building blocks such as a second-generation current conveyor (CCII) and an operational transconductance amplifier (OTA) as an active element with few passive elements. The circuit shows a clear fingerprint of an ideal memristor. The offered emulator circuit can be made to operate in incremental and decremental modes and functions well up to 26.3 MHz. Nonvolatility, Monte Carlo sampling, and corner analysis simulations are executed to verify the robustness of the circuit. The functional verification of the presented circuit is performed using the 0.18- $\mu \text{m}$ CMOS parameter at a supply voltage of ±1.2 V. The experimental demonstration is carried out by making a prototype on a breadboard using ICs AD844AN and CA3080, which exhibits a good agreement with theoretical and simulation results. The layout of the circuit, which requires a total chip area of $75\times 70\,\,\mu \text{m}^{2}$ , is also created. Single/parallel combinations of a memristor, a high-pass filter, and a chaotic system are presented to demonstrate its application.

Floating incremental/decremental flux-controlled memristor emulator circuit based on single VDTA

In this paper, new analog emulator circuits of flux-controlled memristor based on current voltage differencing transconductance amplifier (VDTA) and passive elements are proposed. They emulate both types of memductance, incremental and decremental, solely by interchanging the VDTA output terminals controlled by a simple switch. It uses only one VDTA, two resistors, one capacitor and one multiplier emulating floating memductance. Compared to other designed emulator circuits, they consist of fewer CMOS transistors and have wider output ranges. Theoretical derivations and related results are validated using SPICE simulations. The effectiveness of the proposed memristor circuits is verified by experimental results using commercially available integrated circuits, showing close agreement with theoretical and simulation results and easily reproducible at a low cost. The simulation test results and use of 0.18 μm CMOS technology have shown that the maximum frequency is 2 MHz. The circuit has also been tested for non-volatility features.The application of the proposed floating memristor emulator in designing an FM-to-AM converter confirms the functionality of the proposed circuit.

On-printed circuit board emulator with controllability of pinched hysteresis loop for nanoscale $$\mathrm{TiO}_2$$ TiO 2 thin-film memristor device

Since real memristor devices are still not commercially available to most researchers, modeling a memristor is an effective method to explore its properties. In this paper, a flux-controlled memristor emulator circuit that can correctly mimic the memristive behavior of a real nanoscale $$\mathrm{TiO}_2$$TiO2 thin-film memristor device is presented. The mathematical equations for the proposed emulator are explicitly derived, and the design parameters for the circuit in which the emulator works as a passive memristor with positive memductance are discussed. In addition, the proposed emulator can produce various v---i hysteretic behaviors by controlling the nonlinear polynomial cubic function between the flux and charge inside. The results from numerical simulations in PSpice and MATLAB, as well as the measured results from an implemented emulator circuit on a printed circuit board using off-the-shelf electronics components, demonstrate that a controllable emulator can actually be constructed. This study serves as a foundation for understanding and designing different emulators for nanoscale $$\mathrm{TiO}_2$$TiO2 thin-film memristors at the laboratory level.

A Floating Memristor Emulator Based Relaxation Oscillator

In this paper, a flux-controlled memristor emulator with floating terminals by making use of four current conveyors is newly proposed. By replacing the three resistors in the positive and negative feedback loops of a typical relaxation oscillator respectively, three cases of memristor emulator based oscillating circuits are theoretically constructed and mathematically analyzed. To further probe the practicability and inherent features of the new memristor emulator and oscillator, experimental tests are carried out and the measured experimental results show differences from typical relaxation oscillators, this new memristor emulator based oscillator can provide novel and steady oscillating behaviors. The comparison of measured data with theoretical analysis is in good agreement, which further confirms the practicability of this new memristor emulator and oscillator.