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PRESENTED BY

SAI KRISHNA.R (2-1)

NRIIT

TEJASWI.K(2-1)

NRIIT

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Memristor / M

History

Applications

PhysicsMemristor, HP labs

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THE PROBLEM

Flash memory currently commands 

the vast majority of the multibillion 

dollar non-volatile memory market, 

but experts agree that Flash 

memory feature sizes may not continue to scale well into the near 

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PROPOSED SOLUTION- RRAM

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RRAM- RESISTIVE RAM

Resistive random-accessmemory (RRAM) is a new

non-volatile  memory type 

which promises to replace the existing flash memory

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PRINCIPLE:

Resistive switching memories are based on materials whose resistivity can be electrically 

switched between high and low conductive 

states. RRAM has superior intrinsic scaling characteristics compared to the charge-based 

Flash devices, and potentially small cell size 

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RRAM, one of the most recently proposed alternatives, takes 

advantage of controllable 

resistance changes in thin-oxide 

films. This could potentially 

provide greater density, lower 

power usage, greater speed, 

and lower cost than flash 

memory.

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Memristor, HP labsMemristor symbol

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MEMRISTORS?

Memristors is a short for memory 

resistors which form, according to Lean 

Chua, one among the four basic elements , the other three being 

resistor, inductor, capacitor .

Theoretically, Memristors, a 

concatenation of ´memory resistorsµ, 

are a type of passive circuit elements 

that maintain a relationship between 

the time integrals of current and 

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ANALOGY

A common analogy for a resistor is a pipe that carrieswater. The water itself is analogous to electrical charge,

the pressure at the input of the pipe is similar to voltage,and the rate of flow of the water through the pipe is like

electrical current. Just as with an electrical resistor, theflow of water through the pipe is faster if the pipe is

shorter and/or it has a larger diameter. An analogy for a

memristor is an interesting kind of pipe that expands orshrinks when water flows through it. If water flowsthrough the pipe in one direction, the diameter of the pipe

increases, thus enabling the water to flow faster. If water

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Four interconnected things, mathematics says, can 

be related in six ways. Charge and current, and 

magnetic flux and voltage, are connected through their definitions. That's two. Three more 

associations correspond to the three traditional 

circuit elements. A resistor is any device that, 

when you pass current through it, creates a voltage. For a given voltage a capacitor will store a 

certain amount of charge. Pass a current through 

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2008: HP has a working memristor prototype

End of 199

0s:Research on resistance switching

1971: The theory of the Memristor

1960s:Resistance switching

t

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Nanoscale metal/oxide/metal switches have the potential to transform the market 

for nonvolatile memory and could lead to novel forms of computing. However, progress has been delayed by difficulties in understanding and controlling the 

coupled electronic and ionic phenomena that dominate the behaviour of nanoscale 

oxide devices. An analytic theory of the 'memristor' (memory-resistor) was first developed from fundamental symmetry arguments in 97 , and we recently 

showed that memristor behaviour can naturally explain such coupled electron²ion 

dynamics. Here we provide experimental evidence to support this general model 

of memristive electrical switching in oxide systems. e have built micro- and 

nanoscale TiO2 junction devices with platinum electrodes that exhibit fast bipolar 

nonvolatile switching. e demonstrate that switching involves changes to the electronic barrier at the Pt/TiO2 interface due to the drift of positively charged 

oxygen vacancies under an applied electric field. Vacancy drift towards the 

interface creates conducting channels that shunt, or short-circuit, the electronic 

barrier to switch ON. The drift of vacancies away from the interface annilihilates 

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Al / TiOx / Al µSandwichµ