Welcome Seminar on

MEMRISTOR

24 Aug. 2012

MEMRISTOR

Memristor

Memory Resistor+

Memristor

Analogy Of Memristor

A RESISTOR WITH MEMORY BEHAVES LIKE A PIPE

The diameter of pipe remains same when the current is switched off, until it is switched on again.

The pipe, when the current is switched on again, remembers what current has flowed through it.

Definition of Memristor A memristor is a device whose resistance

varies as a function of flux and current. This allows it to “remember” what has passed through the circuit.

Characterized by Memristance

What Is It? A type of electrical

circuit. The fourth mystery

element that joins the capacitor, resistor, and inductor.

Memristance Memristance is simply charge-dependent

resistance. V(t) = M(q(t))*I(t)

Unit - ohm (Ω)

Symbol

Emergence Of Memristic TheoryTheory was developed in 1971 by

Professor Leon Chua at University of California, Berkeley.

Found while exploring symmetry between the three fundamental passive linear circuit elements

In 2006, R.Stanley Williams developed practical model.

Symmetry Of Relationships

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Symmetry Of Relationships

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

q=CvCapacitors q=CvCapacitorsCapacitors

Symmetry Of Relationships

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Resistors v=Ri

Capacitors q=CvCapacitors

Symmetry Of Relationships

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Φ = Li Inductors

??

v=dΦ/dt i=dq/dt

Resistors v=Ri

q=CvCapacitors

Symmetry Of Relationships

MemristorsΦ=Mq

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Φ = Li Inductors

v=dΦ/dt i=dq/dt

Resistors v=Ri

q=CvCapacitors

Relationship With Other VariablesΦ = M q

dΦ/dt = M(q) dq/dt

V(t) = M(q) I

P = I² M(q)

Memristic State Found when researching ways to overcome

nano-scale manufacturing issues. Memristivity has an inverse square relationship

with thickness of the material, so

smaller = better! Nonvolatile state can be accomplished by

memristors because their state is encoded by impedance (physically), not by voltage.

WORKING

PT PTTiOv(2-x)

TiO2

3 nm

2 nm

OxidizedReduced

(-)ve (+)ve

Applied voltage makes the oxygen vacancies (+ve) to shift towards the –ve voltage.

Benefits Of Memristor TechnologyWould allow for a quicker boot up since

information is not lost when the device is turned off.

Hard Disk + RAM = MEMRISTORUses less energy and produces less heat.Creating a Analog Computer that works

much faster than Digital ones

Benefits Of Memristor Technology Provides greater resiliency and reliability

when power is interrupted in data centers.

Density allows for more information to be stored.

What Sets Memristor Apart ?? Conventional devices use only 0 and 1;

Memristor can use anything between 0 and 1.

Faster than Flash memory. Allow digital cameras to take pictures with

no delay inbetween Innovating nanotechnology due to the fact

that it performs better the smaller it becomes.

What Sets Memristor Apart ?? By changing the speed and strength of the

current, it is possible to change the behavior of the device.

A fast and hard current causes it to act as a digital device.

A soft and slow current causes it to act as an analog device.

Future Technological Significance Hope to one day have

a computer that processes information in the same way as the human brain. Gaining control

over the device could lead to computers that actually learn.

Future Technological SignificanceBeing implemented to do neural

computing. (post office, banks).Pattern recognition and learning.Crossbar latches to replace transistors.New forms signal processing and

control systems.

Not Perfect Yet ! Though hundreds of thousands of

memristor semiconductors have already been built, there is still much more to be perfected.

Needs more defect engineering. No design standards (rules).