MADX: Memristors-As-Drivers for Crossbar logic

Memristors have the potential to not only replace conventional memory, but also to open up new design possibilities because they store 1s and 0s as resistances rather than voltages. A memristor architecture that has attracted interest for its versatility and ease of integration with existing CMOS technologies is the crossbar array. In this paper, I modify the MAD scheme to create the MADX scheme for performing basic logic operations within a crossbar array. Then, I compare this scheme against two of the most well-known schemes, MAGIC and IMPLY. In the case study of a full-adder, both a one-bit and an 8-bit version, the MADX scheme achieves lower latency and substantially lower area requirements than both MAGIC and IMPLY. This is because it is more flexible about storing output values than either, does not destroy input values unlike IMPLY, and has more basic operations. In particular, it has XOR, which neither IMPLY nor MAGIC have and is useful for additionPlan II Honors Progra

Memcapacitive Devices in Logic and Crossbar Applications

Over the last decade, memristive devices have been widely adopted in computing for various conventional and unconventional applications. While the integration density, memory property, and nonlinear characteristics have many benefits, reducing the energy consumption is limited by the resistive nature of the devices. Memcapacitors would address that limitation while still having all the benefits of memristors. Recent work has shown that with adjusted parameters during the fabrication process, a metal-oxide device can indeed exhibit a memcapacitive behavior. We introduce novel memcapacitive logic gates and memcapacitive crossbar classifiers as a proof of concept that such applications can outperform memristor-based architectures. The results illustrate that, compared to memristive logic gates, our memcapacitive gates consume about 7x less power. The memcapacitive crossbar classifier achieves similar classification performance but reduces the power consumption by a factor of about 1,500x for the MNIST dataset and a factor of about 1,000x for the CIFAR-10 dataset compared to a memristive crossbar. Our simulation results demonstrate that memcapacitive devices have great potential for both Boolean logic and analog low-power applications

Hybrid memristor-CMOS implementation of logic gates design using LTSpice

In this paper, a hybrid memristor-CMOS implementation of logic gates simulated using LTSpice. Memristors' implementation in computer architecture designs explored in various design structures proposed by researchers from all around the world. However, all prior designs have some drawbacks in terms of applicability, scalability, and performance. In this research, logic gates design based on the hybrid memristor-CMOS structure presented. 2-inputs AND, OR, NAND, NOR, XOR, and XNOR are demonstrated with minimum components requirements. In addition, a 1-bit full adder circuit with high performance and low area consumption is also proposed. The proposed full adder only consists of 4 memristors and 7 CMOS transistors. Half design of the adder base on the memristor component created. Through analysis and simulations, the memristor implementation on designing logic gates using memristor-CMOS structure demonstrated using the generalized metastable switch memristor (MSS) model and LTSpice. In conclusion, the proposed approach improves speed and require less area

Memristor logic design using driver circuitry

A new lower-power gate design for memristor-based Boolean operations. Such a design offers a uniform cell that is configurable to perform all Boolean operations, including the XOR operation. For example, a circuit to perform the AND operation utilizes a first memristor and a second memristor connected in series. The circuit further includes a switch, where a node of the second memristor is connected to the switch. Furthermore, the circuit includes a third memristor connected to the switch in series, where the switch and the third memristor are connected in parallel to the first and second memristors. Additionally, the first voltage source is connected to the first memristor via a first resistor. In addition, a second voltage source is connected in series to the switch and the third memristor. In such a design, the delay is reduced to a single step and the area is reduced to at most 3 memristors.Board of Regents, University of Texas Syste

Low-power emerging memristive designs towards secure hardware systems for applications in internet of things

Emerging memristive devices offer enormous advantages for applications such as non-volatile memories and in-memory computing (IMC), but there is a rising interest in using memristive technologies for security applications in the era of internet of things (IoT). In this review article, for achieving secure hardware systems in IoT, low-power design techniques based on emerging memristive technology for hardware security primitives/systems are presented. By reviewing the state-of-the-art in three highlighted memristive application areas, i.e. memristive non-volatile memory, memristive reconfigurable logic computing and memristive artificial intelligent computing, their application-level impacts on the novel implementations of secret key generation, crypto functions and machine learning attacks are explored, respectively. For the low-power security applications in IoT, it is essential to understand how to best realize cryptographic circuitry using memristive circuitries, and to assess the implications of memristive crypto implementations on security and to develop novel computing paradigms that will enhance their security. This review article aims to help researchers to explore security solutions, to analyze new possible threats and to develop corresponding protections for the secure hardware systems based on low-cost memristive circuit designs

Memristor-based arithmetic units

The modern computer architecture community is continually pushing the limits of performance, speed, and efficiency. Recently, the ability to satisfy this endeavor with popular CMOS technology has proved difficult, and in many settings, impossible. The community has begun to explore alternatives to standard practices, researching new components such as nanoscale structures. Additional research has applied these new components and their characteristics to rethink the architecture of the latest technology, moving away from the Von Neumann architecture. A leading technology in this effort is the memristor. Memristors are a new class of circuit elements that have the ability to change their resistance value while retaining knowledge of their current and past resistances. Their small form factor, high density, and fast switching times have sparked research in their applications in modern memory hierarchies. However, their utility in arithmetic has been minimally explored. This dissertation describes the prior work in the exploration of memristor technology, fabrication, modeling, and application, followed by the completed research performed in the design and implementation of arithmetic units using memristors. Implementations of popular adders, multipliers, and dividers in the context of memristors are designed using four approaches: IMPLY, hybrid-CMOS, threshold gates, and MAD gates. Each of these approaches has different tradeoffs and benefits for memristor-based design. Although the first three approaches have been defined in prior work, MAD gates are a novel application for memristors proposed that offer lower power, area, and delay as compared to prior approaches. This work explores these benefits for arithmetic unit design. The details of each designs, simulation results, and analyses in terms of complexity and delay and power are presented. For arithmetic units which have been designed or presented in prior work, this research improves upon the design in each metric. Many of the designs are transformed and pipelined to leverage memristor characteristics and the various approaches rather than traditional CMOS and this is discussed in detail. Overall, the proposed designs offer significant improvements to traditional CMOS designs, motivating the effort to continue exploring memristors and their application to modern computer architecture design.Electrical and Computer Engineerin

In-Memory Computing by Using Nano-ionic Memristive Devices

By reaching to the CMOS scaling limitation based on the Moore’s law and due to the increasing disparity between the processing units and memory performance, the quest is continued to find a suitable alternative to replace the conventional technology. The recently discovered two terminal element, memristor, is believed to be one of the most promising candidates for future very large scale integrated systems. This thesis is comprised of two main parts, (Part I) modeling the memristor devices, and (Part II) memristive computing. The first part is presented in one chapter and the second part of the thesis contains five chapters. The basics and fundamentals regarding the memristor functionality and memristive computing are presented in the introduction chapter. A brief detail of these two main parts is as follows: Part I: Modeling- This part presents an accurate model based on the charge transport mechanisms for nanoionic memristor devices. The main current mechanism in metal/insulator/metal (MIM) structures are assessed, a physic-based model is proposed and a SPICE model is presented and tested for four different fabricated devices. An accuracy comparison is done for various models for Ag/TiO2/ITO fabricated device. Also, the functionality of the model is tested for various input signals. Part II: Memristive computing- Memristive computing is about utilizing memristor to perform computational tasks. This part of the thesis is divided into neuromorphic, analog and digital computing schemes with memristor devices. – Neuromorphic computing- Two chapters of this thesis are about biologicalinspired memristive neural networks using STDP-based learning mechanism. The memristive implementation of two well-known spiking neuron models, Hudgkin-Huxley and Morris-Lecar, are assessed and utilized in the proposed memristive network. The synaptic connections are also memristor devices in this design. Unsupervised pattern classification tasks are done to ensure the right functionality of the system. – Analog computing- Memristor has analog memory property as it can be programmed to different memristance values. A novel memristive analog adder is designed by Continuous Valued Number System (CVNS) scheme and its circuit is comprised of addition and modulo blocks. The proposed analog adder design is explained and its functionality is tested for various numbers. It is shown that the CVNS scheme is compatible with memristive design and the environment resolution can be adjusted by the memristance ratio of the memristor devices. – Digital computing- Two chapters are dedicated for digital computing. In the first one, a development over IMPLY-based logic with memristor is provided to implement a 4:2 compressor circuit. In the second chapter, A novel resistive over a novel mirrored memristive crossbar platform. Different logic gates are designed with the proposed memristive logic method and the simulations are provided with Cadence to prove the functionality of the logic. The logic implementation over a mirrored memristive crossbars is also assessed

Design of Hybrid Full Adder using 6T-XOR-Cell for High Speed Processor Designs Applications

Hybrid-logic implementation is highly suitable in the design of a full adder circuit to attain high-speed low-power consumption, which helps to design n any high speed ALUs that can be used in varies processors and applicable for high speed IoT- Application. XOR/XNOR-cell, Hybrid Full Adder (HFA) are the fundamental building block to perform any arithmetic operation. In this paper, different types of high-speed, low-power 6T-XOR/XNOR-cell designs are being proposed and simulated results are presented. The proposed HFA is simulated using a cadence virtuoso environment in a 45nm technology with supply voltage as 0.8V at 1GHz. The proposed HFA consumes a power of 1.555uw, and the delay is 36.692ns.  Layout designs are drawn for both 6T-XOR/XNOR-cell, and 1- bit HFA designs. XOR/XNOR-cells are designed based on the combination of normal CMOS-inverter and Pass Transistor Logic (PTL). Which is used in the design of high end device processors such as ALU that can be implemented for the IoT- design applications