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A Switched Capacitor Memristor Emulator Using Stochastic Computing^{ †}

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## Abstract

**:**

## 1. Introduction

## 2. Theoretical Background

#### 2.1. Memristor Mathematical Description

- (1)
- As Leon Chua noted in [33]: “If it’s NOT pinched, it’s NOT a memristor”. The i-v curve obtained when a periodic signal with zero DC component (voltage or current) is applied to the memristor shows a pinched (at the (v = 0,i = 0) point) hysteresis loop;
- (2)

#### 2.2. Stochastic Logic Operations

## 3. Memristor Emulator Design

#### 3.1. Theoretical Design

#### 3.2. Simulation Results

## 4. Experimental Implementation

#### 4.1. Experimental Setup

#### 4.2. Experimental Results

## 5. Discussion

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Conflicts of Interest

## References

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**Figure 1.**Basic implementation scheme of a SC multiplier in the (0..1) range (AND gate,

**left**) and in the (−1..1) range (XNOR gate,

**right**).

**Figure 2.**Basic implementation schemes (

**a**) of a SC adder using a multiplexer and (

**b**) a stochastic number generator (SGN) which converts a binary encoded number (BEN) to a stochastic encoded number (SEN) using a random number generator (RNG).

**Figure 6.**Simulated $i-v$ characteristic curves of the memristor implemented using Figure 4. Three different frequencies are shown in different colors.

**Figure 7.**$Q-\varphi $ characteristics of the memristor implemented using Figure 4. The different frequencies (in arbitrary units) are shown in different colors.

**Figure 8.**Current signal (response) for different frequencies, as obtained from the simulation. The three different frequencies are shown in different colors and correspond to the ones shown in Figure 6.

**Figure 11.**Three least significant bits of the counter (${b}_{0}$ is the least significant bit) at a specific time.

**Figure 12.**Temporal graphs of the measured response (current signals) of the realized memristor at 3 different frequencies corresponding to the simulated frequencies for driving sine voltage of (

**a**) 100 Hz, (

**b**) 200 Hz, and (

**c**) 400 Hz.

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**MDPI and ACS Style**

de Benito, C.; Camps, O.; Al Chawa, M.M.; Stavrinides, S.G.; Picos, R.
A Switched Capacitor Memristor Emulator Using Stochastic Computing. *Technologies* **2022**, *10*, 39.
https://doi.org/10.3390/technologies10020039

**AMA Style**

de Benito C, Camps O, Al Chawa MM, Stavrinides SG, Picos R.
A Switched Capacitor Memristor Emulator Using Stochastic Computing. *Technologies*. 2022; 10(2):39.
https://doi.org/10.3390/technologies10020039

**Chicago/Turabian Style**

de Benito, Carola, Oscar Camps, Mohamad Moner Al Chawa, Stavros G. Stavrinides, and Rodrigo Picos.
2022. "A Switched Capacitor Memristor Emulator Using Stochastic Computing" *Technologies* 10, no. 2: 39.
https://doi.org/10.3390/technologies10020039