Memristor the fourth element

THE MISSING ELEMENT OF THE CIRCUIT THEORY

Presented byYasar Shafat Qazi

ECE-10-53

The Idea

Memristance

Properties of Memristor

HP Memristor

Applications

Benefits & Future

Conclusion

Theory developed in 1971 by Professor Leon Chua at University of California.

Exploring symmetry between the four fundamental circuit variables.

Charge

Voltage

Current

Flux

..and Time

….a clock variable

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Capacitor (Q & V)

Resistor (V & I)

Inductor (Φ & I)

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Φ = L.i Inductor

No Relation , No device?

v=dΦ/dt i=dq/dt

Capacitor q = C.v

Resistor

v = i.R

Voltage (V)

Current(i)

Charge (q)

Flux (Φ)

Φ = L.i Inductor

Memristor

Φ=M.q

v=dΦ/dt i=dq/dt

Capacitor q = C.v

Resistor

v = i.R

A memristor is Characterized by Memristance

Memristance is simply charge-dependent resistance.

V(t) = Mq(t).I(t)

Unit - ohms (Ω)

MEMRISTOR

Memristor

Memory Resistor+A Crossbar Array Memristors

Circuit Symbol:

Changes Resistance with Applied Voltage

Nonvolatile state is encoded by impedance, not by voltage.

Found when researching ways to overcome Nano-scale manufacturing issues.

Smaller = Better!

Memristance also varies

with Frequency

Plot between Voltage & Current across a memristor

PT PTTiO(2-x)

TiO2

3 nm

2 nm

OxidizedReduced

(-)ve (+)ve

R(TiO2-x) < R(TiO2)

When w=D, R =RON =Low

& when w=0, R=ROFF=High

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

The crossbar topology is composed of a grid of horizontal and vertical traces

Forcing the Memristor to its extreme resistance values (RON and ROFF)

Concept Of Behavior under Different Frequencies is Utilized.

NanowiresNanowires

Memristors

Faster boot

Speed: (Semiconductor) < (Memristor)

Density allows for more information to be stored.

Low Power Consumption

Analog Memory.

Faster than Flash memory.

Innovating Nano Technology due to the fact that it performs better the smaller it becomes.

Creating a Analog Computer that works much faster than Digital ones.

Pattern recognition and learning.

Brain Like Systems

Still In Research Phase.

Needs more precise engineering.

No design standards.

Q, V , I , Φ may not be the only variables in circuit theory.

There can possibly be more than 4 fundamental Circuit elements.

Proposed Elements : MemCapacitor & MemInductor