The document summarizes the modeling of a magnetic tunnel junction (MTJ) using HSPICE. It describes the key components of the MTJ macro-model including electrodes, a decision-making circuit, bi-stable amplification, and a curve-fitting circuit. Simulation results show the MTJ resistance switching between 1.8kΩ and 4.5kΩ as expected. A 1T-1MTJ MRAM cell is also modeled to demonstrate read, write, and hold operations. Finally, a 2x2 MRAM array is shown to verify the design can be extended to larger arrays.
This document is a presentation on spintronics given by Md. Faruk Hossain at Rajshahi University of Engineering & Technology. It provides a brief history of spintronics, defines what spintronics is, and describes some of the key devices and effects in spintronics including giant magnetoresistance, tunnel magnetoresistance, magnetic tunnel junctions, MRAM, and spin field-effect transistors. The presentation outlines both the current state of spintronics research and its potential advantages over conventional electronics, as well as some remaining limitations that need to be addressed.
Detecção de descargas elétricas em mancal de rolamentoCelso LS
The document summarizes the issue of electrical erosion in motor bearings caused by variable frequency drives. It describes how electrical discharges inside bearings can damage components over time. A new technology called the SKF Electrical Discharge Detector Pen is able to detect these early-stage discharges and help identify electrical erosion before visible signs of damage occur. The pen detects magnetic field changes from electrical sparks in bearings to diagnose electrical erosion issues and allow for preventative maintenance.
This document discusses spintronics, which uses the spin of electrons rather than just their charge. It begins by noting limitations of conventional electronics and advantages of spintronics like higher speeds and lower power usage. Giant magnetoresistance is described, including devices like spin valves that use the resistance difference between parallel and antiparallel magnetizations. Later developments included tunnel magnetoresistance and magnetic random access memory using spin transfer torques. Research goals are developing spin transistors and magnetic semiconductors to fully integrate memory, logic, and communication on a chip.
1. The document describes a technical seminar on spintronic technology submitted by a student.
2. Spintronics is an emerging nanotechnology that uses the spin of electrons in addition to or instead of their charge to build devices.
3. One application is magnetoresistive random access memory (MRAM), a new type of non-volatile memory that could replace traditional RAM.
This document provides an overview of spintronics presented by Prince Kushwahe. It introduces spintronics as a field that utilizes the spin of electrons in addition to their charge. Future demands for spintronics are discussed due to limitations of Moore's Law. Key devices are summarized including giant magnetoresistance, spin valves, tunnel magnetoresistance, and magnetic RAM. Research areas like spin transistors, magnetic semiconductors, and spin injection are also covered. The document concludes that spintronics may lead to new devices fusing logic, storage, and sensing to advance computing.
Spintronics utilizes the intrinsic spin property of electrons in addition to their charge to create new devices. Devices like giant magnetoresistance (GMR) sensors and magnetic random access memory (MRAM) make use of electron spin and its interaction with magnetism. GMR sensors detect tiny magnetic fields by measuring resistance changes between parallel and antiparallel electron spin alignments in thin magnetic layers separated by a conductor. MRAM uses magnetic tunnel junctions to store information as the orientation of magnetization, allowing for high density, non-volatile memory. Spintronic devices promise enhanced functionality, higher speeds, and lower power consumption compared to conventional electronics as devices continue shrinking to the nanoscale.
In our conventional electronic devices we use semi conducting materials for logical operation and magnetic materials for storage, but spintronics uses magnetic materials for both purposes. These spintronic devices are more versatile and faster than the present one. One such device is Spin Valve Transistors (SVT).
Spin valve transistor is different from conventional transistor. In this for conduction we use spin polarization of electrons. Only electrons with correct spin polarization can travel successfully through the device. These transistors are used in data storage, signal processing, automation and robotics with less power consumption and results in less heat. This also finds its application in Quantum computing, in which we use Qubits instead of bits.
This document is a presentation on spintronics given by Md. Faruk Hossain at Rajshahi University of Engineering & Technology. It provides a brief history of spintronics, defines what spintronics is, and describes some of the key devices and effects in spintronics including giant magnetoresistance, tunnel magnetoresistance, magnetic tunnel junctions, MRAM, and spin field-effect transistors. The presentation outlines both the current state of spintronics research and its potential advantages over conventional electronics, as well as some remaining limitations that need to be addressed.
Detecção de descargas elétricas em mancal de rolamentoCelso LS
The document summarizes the issue of electrical erosion in motor bearings caused by variable frequency drives. It describes how electrical discharges inside bearings can damage components over time. A new technology called the SKF Electrical Discharge Detector Pen is able to detect these early-stage discharges and help identify electrical erosion before visible signs of damage occur. The pen detects magnetic field changes from electrical sparks in bearings to diagnose electrical erosion issues and allow for preventative maintenance.
This document discusses spintronics, which uses the spin of electrons rather than just their charge. It begins by noting limitations of conventional electronics and advantages of spintronics like higher speeds and lower power usage. Giant magnetoresistance is described, including devices like spin valves that use the resistance difference between parallel and antiparallel magnetizations. Later developments included tunnel magnetoresistance and magnetic random access memory using spin transfer torques. Research goals are developing spin transistors and magnetic semiconductors to fully integrate memory, logic, and communication on a chip.
1. The document describes a technical seminar on spintronic technology submitted by a student.
2. Spintronics is an emerging nanotechnology that uses the spin of electrons in addition to or instead of their charge to build devices.
3. One application is magnetoresistive random access memory (MRAM), a new type of non-volatile memory that could replace traditional RAM.
This document provides an overview of spintronics presented by Prince Kushwahe. It introduces spintronics as a field that utilizes the spin of electrons in addition to their charge. Future demands for spintronics are discussed due to limitations of Moore's Law. Key devices are summarized including giant magnetoresistance, spin valves, tunnel magnetoresistance, and magnetic RAM. Research areas like spin transistors, magnetic semiconductors, and spin injection are also covered. The document concludes that spintronics may lead to new devices fusing logic, storage, and sensing to advance computing.
Spintronics utilizes the intrinsic spin property of electrons in addition to their charge to create new devices. Devices like giant magnetoresistance (GMR) sensors and magnetic random access memory (MRAM) make use of electron spin and its interaction with magnetism. GMR sensors detect tiny magnetic fields by measuring resistance changes between parallel and antiparallel electron spin alignments in thin magnetic layers separated by a conductor. MRAM uses magnetic tunnel junctions to store information as the orientation of magnetization, allowing for high density, non-volatile memory. Spintronic devices promise enhanced functionality, higher speeds, and lower power consumption compared to conventional electronics as devices continue shrinking to the nanoscale.
In our conventional electronic devices we use semi conducting materials for logical operation and magnetic materials for storage, but spintronics uses magnetic materials for both purposes. These spintronic devices are more versatile and faster than the present one. One such device is Spin Valve Transistors (SVT).
Spin valve transistor is different from conventional transistor. In this for conduction we use spin polarization of electrons. Only electrons with correct spin polarization can travel successfully through the device. These transistors are used in data storage, signal processing, automation and robotics with less power consumption and results in less heat. This also finds its application in Quantum computing, in which we use Qubits instead of bits.
This document is a seminar report submitted by Sreenath M to fulfill requirements for a BSc in Electronics from the University of Kerala between 2011-2014. The report focuses on spin valve transistors and was conducted at the College of Applied Science in Adoor, Kerala. It includes an introduction to spintronics and spin valve transistors, as well as sections on the history and physics of giant magnetoresistance and the spin valve effect. The report discusses the working principle, current transfer characteristics, and resistance measurement techniques for spin valve transistors. It was reviewed and approved by the internal and external examiners listed.
A small and brief introduction to spintronics and it's applications. Spintronics has tremendous applications in storage devices,Missile giudance, sensors etc.,
a branch of nano electronics that will improve technology by adding new freedom degrees to electronic for transfer and store information better than electronic devices :)
The magnetically sensitive transistor (also known as the spin transistor or spintronic transistor—named for spintronics, the technology which this development spawned), originally proposed in 1990 and currently still being developed, is an improved design on the common transistor invented in the 1940s. The spin transistor comes about as a result of research on the ability of electrons (and other fermions) to naturally exhibit one of two (and only two) states of spin: known as "spin up" and "spin down". Unlike its namesake predecessor, which operates on an electric current, spin transistors operate on electrons on a more fundamental level; it is essentially the application of electrons set in particular states of spin to store information.
This document discusses spintronics as an emerging technology that utilizes the spin of electrons rather than just their charge. Spintronic devices could offer higher integration density, higher speeds and lower power consumption compared to conventional electronics. Some key advantages of spintronics include non-volatility of magnetic storage and the ability to combine logic and storage functions. The document outlines several spintronic effects and devices such as giant magnetoresistance, spin valves, and magnetic random access memory. It concludes that while spintronics may not replace electronics entirely, it could lead to new devices combining different functionalities and help push computing to quantum levels.
This document is Shishu Pal's seminar report on spintronics submitted in partial fulfillment of a bachelor's degree in electronics and communication engineering. The report contains a declaration by Shishu Pal, a certificate signed by their advisors, acknowledgements, an abstract on spintronics, a table of contents and list of figures. The report explores the emerging field of spintronics which uses the spin of electrons in devices rather than just their charge. It discusses technologies like giant magnetoresistance and applications in memory chips, sensors and other devices.
This presentation introduces spintronics, which uses the spin of electrons rather than just their charge. It discusses key concepts like controlling electron spin and how spintronic devices offer advantages over traditional electronics like lower power consumption and faster operation. Examples covered include giant magnetoresistance (GMR) and its use in hard drive read heads, spin valves, and magnetic random access memory (MRAM). While spintronics faces challenges like controlling spin over long distances, it could enable new devices to process information faster and lead to quantum computing applications.
This document outlines the evolution of spintronics and its applications. It discusses how spintronics was developed to address limitations of Moore's Law, including heat generation and quantum effects at small scales. Giant magnetoresistance was discovered, allowing development of technologies like hard disk drives, magnetic tunnel junctions, and magnetic random access memory. These applications leverage the spin-dependent scattering of electrons in ferromagnetic materials to provide non-volatile data storage and sensing capabilities with advantages in speed, cost and capacity compared to traditional electronics. Spintronics continues to be explored for three-dimensional memory architectures like race track memory.
This document discusses spintronics, which uses the spin of electrons rather than just their charge. Spintronic devices could offer higher speeds, lower power consumption, and new functionalities compared to conventional electronics. Spintronics relies on magnetic materials and the spin states of electrons. One example is giant magnetoresistance (GMR), where the resistance depends on the spin configuration of adjacent magnetic layers. Potential applications include spin-polarized field effect transistors and magnetic random access memory (MRAM), which could provide non-volatile memory with faster speeds and lower costs than existing technologies. Overall, spintronics may lead to new devices and quantum computing approaches that significantly advance information technology.
IEEE presentation based on Spintronics & its semiconductor application specifically.
In the conclusion there is a hyperlink of a video which i'm unable to put here and hence i will give you the address of the video so that you can use the video and make the same hyperlink as i had made here.
TEDxCaltech-David Awschalom - Spintronics ( On YouTube)
video : 6:21- 7:13 (in video)
Spintronics is an emerging field that uses electron spin rather than charge to carry information. It promises devices with enhanced functionality, higher speeds, and lower power consumption compared to traditional electronics. Spintronic devices work by manipulating the spin states of electrons in ferromagnetic materials using magnetic fields. Potential applications include magnetic RAM that retains data when power is off, magnetic sensors, and spin transistors. Spintronics may enable smaller, more energy efficient devices and become comparable to electronics within 10 years due to its non-dissipative nature.
Spintronics is a NANO technology which deals with spin dependent properties of an electron instead of charge dependent properties.
One of the main advantage of spintronics over electronics is the magnets tend to stay magnetize which is sparking in the industry an interest for replacing computer’s semiconductor based components with magnetic ones, starting with the RAM.
With an all-magnetic RAM, it is now possible to have a computer that retains all the information put into it. Most importantly, there will be no ‘boot-up’ waiting period when power is turned on.
Another promising feature of spintronics is that it doesn’t require the use of unique and specialized semiconductor, there by allowing it to work with common metals like Cu, Al, Ag.
Spintronics will use less power than conventional electronics, because the energy needed to change spin is a minute fraction of what is needed to push charge around.
Conventional electronic devices ignore the spin property and rely strictly on the transport of the electrical charge of electrons.
Adding the spin degree of freedom provides new effects, new capabilities and new functionalities.
This presentation provides an overview of spintronics and magnetoresistive random access memory (MRAM). Spintronics uses electron spin rather than just charge to store and transfer information, enabling benefits like lower power and faster speeds. The basic principle is that electron spin can be in one of two states, representing 1s and 0s. Technologies like giant magnetoresistance and tunnel magnetoresistance take advantage of electron spin states and resistance changes to read and write data. MRAM in particular combines speed of SRAM and density of DRAM with non-volatility of flash memory, but overcoming challenges like cost and density required further research developments.
This document provides an introduction and abstract for a seminar report on spintronics. It was submitted by B. Dhana Lakshmi to Jawaharlal Nehru Technological University in partial fulfillment of a Bachelor of Technology degree in Electronics and Communication Engineering. The abstract indicates that the seminar will cover topics such as spintronic devices including magnetic random access memory, advances in spintronics, and applications in areas such as magnetic biosensing. It provides key definitions for spintronics and lists chapters that will be included in the seminar report.
This document discusses spintronics, which uses electron spin rather than charge to store and transmit information. It describes giant magnetoresistance (GMR) and how controlling electron spin can enable lower power devices like MRAM and spin transistors. These spintronic devices could combine data storage, processing and communication on a single chip. While promising faster speeds and denser integration, challenges remain in controlling spin over long distances and integrating spintronic techniques with semiconductor technology.
Spintronics is an emerging field that uses electron spin rather than charge to carry information. It promises devices that are much smaller, faster, and denser than conventional electronics. Spintronic devices could enable an atom-sized computer operating at light speed with memory thousands of times denser. Giant magnetoresistance is a key spintronic effect that allows read heads to detect much weaker magnetic fields, increasing data storage capacity. Electron spin qubits in spintronic devices can exist in superpositions of states, enabling massive parallelism for quantum computing.
El documento describe los sistemas de gestión medioambiental (SGMA), que son conjuntos de procedimientos para ayudar a las empresas a cumplir con la legislación ambiental, mejorar su comportamiento ambiental y comunicarlo externamente. Los SGMA tienen como objetivo garantizar la mejora del comportamiento medioambiental de las empresas en áreas como recursos naturales, emisiones, agua y suelo. Existen dos sistemas principales: el Reglamento EMAS de la UE y la norma internacional ISO 14001.
This document discusses measuring customer satisfaction with service quality using the American Customer Satisfaction Index (ACSI) model. It was applied to the Macedonian mobile telecommunications industry to understand how customers perceive service quality and satisfaction with three major providers (T-Mobile, ONE, VIP). A survey was conducted and it was found that overall perceived service quality did not meet customer expectations and satisfaction levels were low. The document reviews factors that influence customer satisfaction and the importance of customer relationship marketing for customer loyalty and retention.
This document is a seminar report submitted by Sreenath M to fulfill requirements for a BSc in Electronics from the University of Kerala between 2011-2014. The report focuses on spin valve transistors and was conducted at the College of Applied Science in Adoor, Kerala. It includes an introduction to spintronics and spin valve transistors, as well as sections on the history and physics of giant magnetoresistance and the spin valve effect. The report discusses the working principle, current transfer characteristics, and resistance measurement techniques for spin valve transistors. It was reviewed and approved by the internal and external examiners listed.
A small and brief introduction to spintronics and it's applications. Spintronics has tremendous applications in storage devices,Missile giudance, sensors etc.,
a branch of nano electronics that will improve technology by adding new freedom degrees to electronic for transfer and store information better than electronic devices :)
The magnetically sensitive transistor (also known as the spin transistor or spintronic transistor—named for spintronics, the technology which this development spawned), originally proposed in 1990 and currently still being developed, is an improved design on the common transistor invented in the 1940s. The spin transistor comes about as a result of research on the ability of electrons (and other fermions) to naturally exhibit one of two (and only two) states of spin: known as "spin up" and "spin down". Unlike its namesake predecessor, which operates on an electric current, spin transistors operate on electrons on a more fundamental level; it is essentially the application of electrons set in particular states of spin to store information.
This document discusses spintronics as an emerging technology that utilizes the spin of electrons rather than just their charge. Spintronic devices could offer higher integration density, higher speeds and lower power consumption compared to conventional electronics. Some key advantages of spintronics include non-volatility of magnetic storage and the ability to combine logic and storage functions. The document outlines several spintronic effects and devices such as giant magnetoresistance, spin valves, and magnetic random access memory. It concludes that while spintronics may not replace electronics entirely, it could lead to new devices combining different functionalities and help push computing to quantum levels.
This document is Shishu Pal's seminar report on spintronics submitted in partial fulfillment of a bachelor's degree in electronics and communication engineering. The report contains a declaration by Shishu Pal, a certificate signed by their advisors, acknowledgements, an abstract on spintronics, a table of contents and list of figures. The report explores the emerging field of spintronics which uses the spin of electrons in devices rather than just their charge. It discusses technologies like giant magnetoresistance and applications in memory chips, sensors and other devices.
This presentation introduces spintronics, which uses the spin of electrons rather than just their charge. It discusses key concepts like controlling electron spin and how spintronic devices offer advantages over traditional electronics like lower power consumption and faster operation. Examples covered include giant magnetoresistance (GMR) and its use in hard drive read heads, spin valves, and magnetic random access memory (MRAM). While spintronics faces challenges like controlling spin over long distances, it could enable new devices to process information faster and lead to quantum computing applications.
This document outlines the evolution of spintronics and its applications. It discusses how spintronics was developed to address limitations of Moore's Law, including heat generation and quantum effects at small scales. Giant magnetoresistance was discovered, allowing development of technologies like hard disk drives, magnetic tunnel junctions, and magnetic random access memory. These applications leverage the spin-dependent scattering of electrons in ferromagnetic materials to provide non-volatile data storage and sensing capabilities with advantages in speed, cost and capacity compared to traditional electronics. Spintronics continues to be explored for three-dimensional memory architectures like race track memory.
This document discusses spintronics, which uses the spin of electrons rather than just their charge. Spintronic devices could offer higher speeds, lower power consumption, and new functionalities compared to conventional electronics. Spintronics relies on magnetic materials and the spin states of electrons. One example is giant magnetoresistance (GMR), where the resistance depends on the spin configuration of adjacent magnetic layers. Potential applications include spin-polarized field effect transistors and magnetic random access memory (MRAM), which could provide non-volatile memory with faster speeds and lower costs than existing technologies. Overall, spintronics may lead to new devices and quantum computing approaches that significantly advance information technology.
IEEE presentation based on Spintronics & its semiconductor application specifically.
In the conclusion there is a hyperlink of a video which i'm unable to put here and hence i will give you the address of the video so that you can use the video and make the same hyperlink as i had made here.
TEDxCaltech-David Awschalom - Spintronics ( On YouTube)
video : 6:21- 7:13 (in video)
Spintronics is an emerging field that uses electron spin rather than charge to carry information. It promises devices with enhanced functionality, higher speeds, and lower power consumption compared to traditional electronics. Spintronic devices work by manipulating the spin states of electrons in ferromagnetic materials using magnetic fields. Potential applications include magnetic RAM that retains data when power is off, magnetic sensors, and spin transistors. Spintronics may enable smaller, more energy efficient devices and become comparable to electronics within 10 years due to its non-dissipative nature.
Spintronics is a NANO technology which deals with spin dependent properties of an electron instead of charge dependent properties.
One of the main advantage of spintronics over electronics is the magnets tend to stay magnetize which is sparking in the industry an interest for replacing computer’s semiconductor based components with magnetic ones, starting with the RAM.
With an all-magnetic RAM, it is now possible to have a computer that retains all the information put into it. Most importantly, there will be no ‘boot-up’ waiting period when power is turned on.
Another promising feature of spintronics is that it doesn’t require the use of unique and specialized semiconductor, there by allowing it to work with common metals like Cu, Al, Ag.
Spintronics will use less power than conventional electronics, because the energy needed to change spin is a minute fraction of what is needed to push charge around.
Conventional electronic devices ignore the spin property and rely strictly on the transport of the electrical charge of electrons.
Adding the spin degree of freedom provides new effects, new capabilities and new functionalities.
This presentation provides an overview of spintronics and magnetoresistive random access memory (MRAM). Spintronics uses electron spin rather than just charge to store and transfer information, enabling benefits like lower power and faster speeds. The basic principle is that electron spin can be in one of two states, representing 1s and 0s. Technologies like giant magnetoresistance and tunnel magnetoresistance take advantage of electron spin states and resistance changes to read and write data. MRAM in particular combines speed of SRAM and density of DRAM with non-volatility of flash memory, but overcoming challenges like cost and density required further research developments.
This document provides an introduction and abstract for a seminar report on spintronics. It was submitted by B. Dhana Lakshmi to Jawaharlal Nehru Technological University in partial fulfillment of a Bachelor of Technology degree in Electronics and Communication Engineering. The abstract indicates that the seminar will cover topics such as spintronic devices including magnetic random access memory, advances in spintronics, and applications in areas such as magnetic biosensing. It provides key definitions for spintronics and lists chapters that will be included in the seminar report.
This document discusses spintronics, which uses electron spin rather than charge to store and transmit information. It describes giant magnetoresistance (GMR) and how controlling electron spin can enable lower power devices like MRAM and spin transistors. These spintronic devices could combine data storage, processing and communication on a single chip. While promising faster speeds and denser integration, challenges remain in controlling spin over long distances and integrating spintronic techniques with semiconductor technology.
Spintronics is an emerging field that uses electron spin rather than charge to carry information. It promises devices that are much smaller, faster, and denser than conventional electronics. Spintronic devices could enable an atom-sized computer operating at light speed with memory thousands of times denser. Giant magnetoresistance is a key spintronic effect that allows read heads to detect much weaker magnetic fields, increasing data storage capacity. Electron spin qubits in spintronic devices can exist in superpositions of states, enabling massive parallelism for quantum computing.
El documento describe los sistemas de gestión medioambiental (SGMA), que son conjuntos de procedimientos para ayudar a las empresas a cumplir con la legislación ambiental, mejorar su comportamiento ambiental y comunicarlo externamente. Los SGMA tienen como objetivo garantizar la mejora del comportamiento medioambiental de las empresas en áreas como recursos naturales, emisiones, agua y suelo. Existen dos sistemas principales: el Reglamento EMAS de la UE y la norma internacional ISO 14001.
This document discusses measuring customer satisfaction with service quality using the American Customer Satisfaction Index (ACSI) model. It was applied to the Macedonian mobile telecommunications industry to understand how customers perceive service quality and satisfaction with three major providers (T-Mobile, ONE, VIP). A survey was conducted and it was found that overall perceived service quality did not meet customer expectations and satisfaction levels were low. The document reviews factors that influence customer satisfaction and the importance of customer relationship marketing for customer loyalty and retention.
Rizwan Iqbal is seeking a job that provides growth, excellence, and satisfaction. He has over 5 years of experience as a Senior Accounts Officer at Cambridge Garments Industries, where he developed expertise in cash flow management, financial forecasting, and risk management. He is proficient in finance software like Excel and ERP packages. Currently, he is responsible for budgeting and reporting actual cash flow to the CFO, managing treasury cycles like supplier payments and bank reconciliations, and overseeing fabric stock operations at Cambridge Garments. Prior to this, he worked as an Assistant Accountant at a fast food restaurant handling financial tasks like transaction recording and bank reconciliations.
El documento analiza las diferencias entre dos profesores descritos en un video. Un profesor era más frío y menos comunicativo con los estudiantes, mientras que el otro era más apasionado y lograba captar más la atención de los estudiantes. También discute diferentes estilos de enseñanza y acciones positivas y negativas de los profesores como interactuar con los estudiantes y captar su atención.
Mohammed J. Safadi is seeking a senior position in accountancy, finance, or HR. He has over 10 years of experience working in accounting roles. Currently, he works as both the Senior Accountant and HR Manager for City Compass Cont. in Abu Dhabi and Dubai, where his responsibilities include managing accounts receivable, payroll, expenses, and more. He holds a Bachelor's Degree in Business Administration Management and is proficient in Microsoft Office, QuickBooks, and Windows operating systems.
preparación de candidatos al empleo. Herramientas para el éxito en el mercado laboral.
מפגש אימון ממוקד בהצלחה בגישה לשוק העבודה המודרני.
Coaching session aimed toward an effective job seeking and success in your search
El documento describe la importancia de que los docentes consideren varios criterios al seleccionar los medios educativos para sus alumnos. Específicamente, los medios deben corresponder a los objetivos y capacidades de los alumnos, sus características individuales como su ritmo de aprendizaje, y deben estar a un nivel de sofisticación adecuado para ellos. Además, aunque el costo es un factor, el medio óptimo no debe limitarse por ello, y se deben utilizar los recursos disponibles.
El documento describe las diferentes funciones del lenguaje, incluyendo la función emotiva o expresiva, conativa o apelativa, referencial, metalingüística, fática o de contacto, y estética o poética. Explica brevemente cada función y su importancia para la comunicación.
Orientación laboral y búsqueda de empleo. Facultad de Ciencias Ambientales UAHRoberto Ruiz Robles
Jornada de orientación laboral y búsqueda de empleo, para alumnos de los últimos cursos de ciencias ambientales. Busqueda de empleo 2.0, networking, eventos claves del sector ambiental, marca personal, uso de redes sociales para la búsqueda de empleo y creación de red de contactos...
This document outlines a mentoring program for the Gvahim Mentoring Group (GMG) with the mission to equip mentors to support Gvahim entrepreneurs. The 24-part syllabus covers topics like establishing expectations, understanding mentees' projects, assisting with goals and marketing, and advanced mentoring techniques. It aims to provide mentors with the tools and framework needed to guide mentees through their projects development from start to finish. A matching process will pair each mentor and mentee, and a committee will oversee training, matching, and conflict resolution.
Stratello : choisir les indicateurs pour piloter son parcours clients?Laurence EVRARD
Piloter les indicateurs de l'Expérience client c'est choisir des indicateurs en fonction de vos parcours clients et non plus uniquement canal par canal.
Découvrez les étapes de notre méthodologie pour choisir et mettre en oeuvre les KPI qui vont vous permettre d'optimiser vos parcours clients.
- The document discusses banana cultivation, including its botanical classification as Musa sp. and originating from Southeast Asia.
- It provides information on major banana producing states in India like Maharashtra, Tamil Nadu, and Karnataka. Optimal growing conditions and important cultivars are also mentioned.
- Cultural practices for banana cultivation are outlined, including land preparation, planting, spacing, fertilizer application, intercropping, and pest and disease management.
Design of STT-RAM cell in 45nm hybrid CMOS/MTJ processEditor IJCATR
This paper evaluates the performance of Spin-Torque Transfer Random Access Memory (STT-RAM) basic memory cell
configurations in 45nm hybrid CMOS/MTJ process. Switching speed and current drawn by the cells have been calculated and
compared. Cell design has been done using cadence tools. The results obtained show good agreement with theoretical results.
STUDY OF SPIN TRANSFER TORQUE (STT) AND SPIN ORBIT TORQUE (SOT) MAGNETIC TUNN...elelijjournal
Magnetic Random Access Memory (MRAM) is a promising candidate to be the universal non-volatile (NV) storage device. The Magnetic Tunnel Junction (MTJ) is the cornerstone of the NV-MRAM technology. 2- terminal MTJ based on Spin Transfer Torque (STT) switching is considered as a hot topic for academic and industrial researchers. Moreover, the 3-terminal Spin Orbit Torque (SOT) MTJ has recently been considered as a hopeful device which provides an increased reliability thanks to independent write and read paths. Since both MTJ devices (STT and SOT) seem to revolutionize the data storage market, it is necessary to explore their compatibility with very advanced CMOS processes in terms of transistor sizing and performance. Assuming a good maturity of the magnetic processes that would enable to fabricate small junctions, simulation results show that the existing advanced sub-micronic CMOS processes can drive the required writing current with reasonable size of transistors confirming the high density feature of MRAMs. At 28 nm node, the minimum transistor size can be used by the STT device. The SOT device shows remarkable energy efficiency with 6× improvement compared with the STT technology. Results are very encouraging for future complex hybrid magnetic/CMOS integrated circuits (ICs).
Efficiency, reliability, high power quality and continuous operation are important aspects in electric vehicle attraction system. Therefore, quick fault detection, isolation and enhanced fault-tolerant control for open-switches faults in inverter driving systems become more and more required in this filed. However, fault detection and localization algorithms have been known to have many performance limitations due to speed variations such as wrong decision making of fault occurrence. Those weaknesses are investigated and solved in this paper using currents magnitudes fault indices, current direct component fault indices and a decision system. A simulation model and experimental setup are utilized to validate the proposed concept. Many simulation and experimental results are carried out to show the effectiveness of the proposed fault detection approach.
A Design Technique To Reduce Nbti Effects From 5t Sram CellsIJERA Editor
This paper focuses on designing an NBTI tolerant system by addressing the major reason of NBTI especially the devices that consists of SOC. To address this issue a thorough study of 5T SRAM cells has been done. This paper is based on idea of switch capacitors and the fact that only few transistors are ON at any particular time. RD model is primary and base model that us used to describe NBTI and aging degradation in this paper The proposed technique improve read power by 8% and leakage power by 12.87%
Simulation of a 13-Level Inverter with Facts Capability for Distributed Energ...IJMTST Journal
This Paper Presents A whole New resonant twin active bridge(DAB) topology, that uses a tuned inductor-capacitor-inductor(LCL) network. As compared to ancient DAB topologies, the planned topologies significantly reduced the bridge current, lowering every physical phenomenon and alter losses and conjointly VA rating associated with the bridges. The performance of the DAB is investigated using a mathematical model at a lower place varied operational conditions. Experiment results of a model is reduced the outflow current of the circuit. are presented with discussion to demonstrate the improved performance of the LCL DAB topology. Result clearly that the planned DAB Topology provide higher efficiency over an oversized vary of every input voltage and as compared to ancient DAB topology
This document summarizes a research paper on fuzzy control of a multicell converter. It begins with an introduction to stacked multicell converters, which allow sharing of voltage and current stresses across switches. It then discusses the topology and operation of the multicell converter. Sinusoidal pulse width modulation is used to control the output voltage. Fuzzy logic control is then proposed to control the RMS voltage value using MATLAB. Simulation results show that total harmonic distortion is reduced with increasing voltage levels in the multicell converter output waveform. Open and closed loop control of a 6x2 multicell converter are analyzed through MATLAB simulation.
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SPIN TORQUE TRANSFER MRAM AS A UNIVERSAL MEMORYIJERA Editor
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Analysis of Modeling of Current Differential Protection
12SETMVD0231_PriyaPandey
1. HSPICE Based Macro-model of
Magnetic Tunnel Junctions
Niharika S. Vranda Baweja Priya Pandey
M.Tech VLSI(1st
Year ) M.Tech VLSI(1st
Year ) M.Tech VLSI(1st
Year )
VIT University VIT University VIT University
Under The Guidance Of:
Prof. Ramakrishnan V N
VLSI Division
VIT University
Tamil Nadu, India
Abstract – Metal tunnel junctions (MTJs) are one of the
emerging trends in the memory designing that can store
the bit ‘0’ or ‘1’ depending on the resistivity of the device.
When the relative magnetic orientation of the two layers is
parallel, the device has a low resistance. When the two
layers are antiparallel, the device has a high resistance.
This work deals with the modeling of the characteristics of
MTJ sub circuit using HSPICE simulator. The sub circuit
is modeled as a two-terminal device exhibiting the electrical
characteristics of an STT-MTJ, including all the major
characteristics of an MTJ. Further The modeled MTJ is to
be connected along with an NMOS device to act as a basic
1T-1MTJ memory cell called as an MRAM cell. The
MRAM is designed to efficiently store, hold and retrieve bit
stored in it.
Keyword – Magnetic Tunnel Junction (MTJ), Spin
Transfer Torque (STT), MRAM cell
I. INTRODUCTION
Magnetic Tunnel Junctions are those devices which
have the property of magneto resistance. The relative magnetic
orientation of two ferromagnetic layers which are separated by
an insulator estimates the electrical resistance of the device. In
case of parallel relative orientation of the two magnetic layers,
the device exhibits low resistance, and in case of anti-parallel
relative orientation, it exhibits high resistance. One of the two
layers is generally fixed by anti-ferromagnetically coupling it.
The fixed layer has high coercivity and its orientation is not
changed in normal condition. The change in the magnetic
orientations of the free layer relative to the fixed layer will
determine the resistance of the device, and this can be helpful
in storing the binary data in the MTJ, which is used as a basic
storage element in the MRAM cell.
The direction of the magnetizations of the ferromagnetic
layers can be switched individually by an external magnetic
field. If the magnetizations of the two layers are in a parallel
orientation, then it is more likely that the electrons will tunnel
through the insulating film compared to if they are in the
antiparallel orientation. Such a junction can be switched
between the two states of electrical resistance, one with low
resistance, and other with very high resistance.
The MTJ and MRAM cell can be modeled and realized in
several ways, depending upon the performance of the device
and the materials used. The electrical behavior of an MTJ can
be realized and implemented using a SPICE sub-circuit which
is capable to exhibiting the same performance as an MTJ,
which can be further used to implement a D flip flop, where
the MTJ is used as a data storage element[1]
. The STT MRAM
can be driven by using an asymmetrical vertical silicon gate
Nano-wire gate all around select device (GAA select device)
using Verilog-A. Perpendicular magnetic anisotropy (MTJ)
multilayer structure is stacked above the GAA select device
and the asymmetry in the critical switching current of an MTJ
is exploited by a matching asymmetric drive current select
device that can be helpful in achieving significant reduction in
the power dissipation [2]
. The proposed design targets to attain
the optimistic figure of 4F2
array density, where F is the
feature size, and 4F2
is the maximum 2-D density which can
be achieved. A 4F2
buried-source-line STT MRAM cell
structure with vertical gate all around, cylindrical buried
source NMOS transistor is proposed. The magnetic tunnel
junction multi-layer structure is stacked above the select
device, where both occupy the same 2-D area [3]
. A non-
volatile memory based on STT-MTJ used as a Spintronics
device for Field Programmable Gate Array (FPGA) and
System on Chip (SoC) circuits is presented, which makes the
device fully non-volatile by permanently storing all the data
processed in the Spin-MTJ cells [4]
. Three nonvolatile flip-flop
(FF)/SRAM cells utilizing a single magnetic tunneling
2. junction as nonvolatile resistive element are proposed. These
cells have the same core (6T) but employing different numbers
of MOSFETs to implement the instantly ON, normally OFF
operation mode. Additional transistors have been utilized for
the restore operation to make sure that the data stored in the
circuitry can be written back into the FF core once the power
is made available to it [5]
.
II. PROPERTIES OF MTJ
1. MTJs are typically current controlled devices. That is
the resistance of the MTJ is directly dependent on the
current through it. An MTJ aligns its magnetic
orientation in parallel state (low resistance) if the
current flows from the fixed terminal to the flexible
terminal, in anti-parallel state (high resistance) if the
current flow is from the flexible terminal to the fixed
terminal. Hence, conventionally the bit stored is said
to be “1” if the MTJ is in parallel (low resistance
state) and “0” if the MTJ is in anti-parallel (high
resistance) state.
2. The critical switching currents for both the parallel
and anti-parallel states are different indicating that
the switching effort involved in the two switches are
different [2]. With each switching, a switching time
is associated and is given by the relation[1],
Icrit = ICrit0 [1 – kB*T/E* ln(tp/t0)]
Where, „ICrit0‟ is the critical switching current for
the respective states.
3. Each MTJ is associated with a parameter called TMR
ratio, given by
TMR = ( Rap – Rp ) / Rp
Where Rp is the resistance of MTJ in parallel state
and Rap is the resistance of MTJ in anti-parallel state.
III. THE MACRO MODEL OF THE MTJ IN HSPICE
In this work, the electric behavior of the MTJ is modeled in
HSPICE. The model was built by using voltage controlled
resistances, various current, muxes, capacitors and amplifiers.
The following section describes the basic components of the
macro-model.
A. Electrodes:
The MTJ is basically a two terminal device. One of
them is considered as fixed terminal and the other the
flexible terminal; meaning its magnetic orientation is
flexible. In this model, we have started by connecting
a voltage controlled resistor between the two
electrodes of the device. The control signal for this
resistor is generated by using a control circuitry. A
small capacitance is also modeled between the
terminals to account for the parasitic effects.
B. Circuit for Decision making:
In the modeling of MTJ it is necessary to come up
with a decision mechanism to accurately switch
between the high resistance and low resistance states.
In this stage, the current through MTJ is first
sampled. The sampled value is then compared with
the standard switching currents for parallel and anti-
parallel states. The two standard switching currents
are modeled using current sources representing the
switching values. Based on this comparison, an
output signal is generated that tells whether to switch
the MTJ to parallel state or anti-parallel state. The
behavior of the decision circuit modeled using
current sources and mux is as follows:
Vdecision = +1 V, when IMTJ > Ip
= -1 V, when IMTJ < Iap
The critical currents for parallel [Ip] and anti-parallel
[Iap] switching are 325uA and -425uA respectively
[1] .The decision works such that if the last decision
was 1V then the MTJ should switch to anti-parallel
state; If the last decision was -1V then the MTJ
should switch to parallel state.
C. The Bi-stable amplification stage:
The bi-stable circuit is used to indicate the present
state of the MTJ device. This stage is modeled by
using the bi-stable amplifier circuit and a feedback
circuit to input the initial condition of the MTJ to be
parallel or anti-parallel. In this work, the initial state
of the MTJ is modeled to be in the anti-parallel state.
The capacitor feedback loop was used in the design.
The behavior of the bi-stable element can be
described as follows
Vstate = +10 V, when last Vdecision was −1 V
= -10 V, when last Vdecision was +1 V
Here the voltage level +10 represents the antiparallel
or the high resistance state and the voltage level -10
represents the parallel or low resistance state.
D. Curve fit circuit:
3. The curve fitting circuit is designed to generate the
final control voltage for the switching of the voltage
controlled resistor connected between the two
terminals of the MTJ. The fitting circuit used in this
design is of Gaussian profile. It is designed in such a
way as to allow the designer to state the parallel and
anti-parallel resistance values required in the design
in the fitting curve. The behavior of the curve fitting
circuit for Gaussian profile can be modeled as
follows
Vctrl = 1 V, when Vstate is −10 V
= (RAP/ RP )× 1 V, when Vstate is + 10 V
The control voltage is scaled to make the output lie
within the TMR ratio of MTJ. For this design, we
have used standard parallel and anti-parallel
resistance as 1.8kΩ and 4.5kΩ respectively[1]. The
Gaussian curve fitting equation is given by,
Vo = Vctrl × exp(-VMTJ ^2/2c^2).
Where c^2 is the curve fitting parameter, given by the bias
voltage that makes Vo to drop to 30% of its original value.
The signal Vo is the final control voltage that controls the
switch between the states.
IV. TYPICAL MRAM CELL
The typical MRAM cell can be formed by using one NMOS
that acts as a select device and one MTJ. The select device is
used to activate or deactivate the MTJ device as and when
required by the design. The select device are designed to
provide good access times and better driving currents for the
MTJ[2]. The structure of 1T MRAM cell is sown in figure 1.
Fig 1.Typical 1T MRAM cell
The flexible electrode of the MTJ is connected to bit line
(BL). The basic structure can be replicated in both directions
to obtain an array of MRAM cells.
V. SIMULATION RESULTS
The macro modeling of MTJ was carried out in HSPICE. The
standard values of critical currents (Ic0) and other parameters
used for the design are listed in the table below [1].
SL NO PARAMETER VALUE
1. Ic0 (Parallel) 3.25uA
2. Ic0 (Antiparallel) -4.25uA
3. Rp 1.8K Ω
4. Rap 4.5 K Ω
5. Initial state Anti-parallel
Table1. Standard values used in the design [1]
Fig 2: MTJ simulated using a triangular current source
The model was simulated using a triangular current source of
various pulse widths to verify the resistance switching
characteristics. The resistance of the MTJ is found to switch
between 1.8KΩ and 4.5KΩ with the critical currents specified
in the design. The working of the macro model was verified
by observing the fact that the device switched to anti-parallel
mode (high resistance) when the current across MTJ is greater
than critical switching current of 325uA and vice versa
4. Fig 3: 1T MRAM cell (Read, write and hold operations)
Fig 4: 2X2 MRAM cell (read, write, hold operations)
Fig 5: 2X2 MRAM cell (read, write, hold operations)
Fig 6 : 2X2 MRAM cell (read, write, hold operations)
Fig 7: 2X2 MRAM cell (read, write, hold operations)
The figure 2 shows the read, write and hold operation of the
single transistor MRAM cell modelled in the 45nm
technology. The antiparallel state (high resistance) represents
the bit 0 and the parallel state (low resistance) represents the
bit 1. The MRAM cell is designed as represented in fig 1. The
cell is active whenever the word line (WL) is asserted.
Initially, the MTJ will be in the anti parallel state as designed
for this work. A bit „1‟ is stored by making the bit line (BL)
high and select line (SL) low so that the current flow is from
the fixed electrode of MTJ to the flexible electrode. This
makes the MTJ to align to parallel or low resistance state
indicating the stored bit „1‟. A bit 0 is stored by making the bit
line (BL) low and select line (SL) high so that the current flow
is from the flexible electrode of MTJ to the fixed electrode.
This makes the MTJ to align to anti parallel or high resistance
state indicating the stored bit „0‟. The read operation is
performed by pre charging the bit line (BL) to the optimum
pre charge value of 0.4 V [2] and asserting the word line
simultaneously.
The MRAM array can be formed by replicating this basic
structure in both dimensions. The figure 3, 4, 5 and 6 verify
the working of 2X2 MRAM memory array. The structure can
be similarly replicated to obtain NXN memory array.
VI. RESULT AND DISCUSSION
The Magnetic tunnel Junction (MTJ) was modeled in the
HSPICE tool. The model was built by using voltage controlled
resistances, various current, muxes, capacitors and amplifiers.
The resistance of the device was designed to switch between
1.8k Ω and 4.5k Ω with the standard switching currents for
parallel and anti-parallel states. The model was simulated
using a triangular current wave of various pulse widths to
verify the resistance switching characteristics. The usefulness
of the modeled MTJ as a non-volatile memory element was
proposed by designing a 1T MRAM cell and verifying the
read, write and hold operation. A basic 2X2 MRAM array
structure was similarly designed to emphasize the fact that the
scope of the designed cells can be extended by replicating
them in both dimensions to design an NXN MRAM memory
array.
5. REFERENCES
[1] Jonathan D. Harms, Student Member, Farbod Ebrahimi, Xiaofeng Yao,"
SPICE Macromodel of Spin-Torque-Transfer-Operated Magnetic
Tunnel Junctions," IEEE TRANSACTIONS ON ELECTRON
DEVICES, VOL. 57, NO. 6, JUNE 2010
[2] Shivam Verma, Sanjay Mahawar and Brajesh Kumar Kaushik,” Low
Power STT MRAM Cell With Asymmetric Drive Current Vertical GAA
Select Device”
[3] Shivam Verma, Shalu Kaundal, Student Member and Brajesh Kumar
Kaushik,” Novel 4F2 Buried-Source-Line STT MRAM Cell With
Vertical GAA Transistor as Select Device” IEEE TRANSACTIONS ON
NANOTECHNOLOGY, VOL. 13, NO. 6, NOVEMBER 2014
[4] Weisheng Zhao, Eric Belhaire and Claude Chappert,” Spin-MTJ based
Non-Volatile Flip-Flop” Proceedings of the 7th IEEE International
Conference on Nanotechnology August 2 - 5, 2007, Hong Kong
[5] Ke Chen, Jie Han, and Fabrizio Lombardi,” On the Nonvolatile
Performance of Flip-Flop/SRAM Cells With a Single MTJ”, IEEE
.TRAN
TRANSACTIONS ON VERY LARGE SCALE INTEGRATION
(VLSI) SYSTEMS, VOL. 23, NO. 6, JUNE 2015