THANSAL K Y
pediain.com
Known Three fundamental passive circuit elements:
Resistor, Inductor, Capacitor.
pediain.com
Does a fourth fundamental element exist? v Resistor dv=Rdi Capacitor dq=Cdv q
i
Inductor
Memristor
Leon the existence of memristor in 1971
In 2008Chua a teamproposed leaddF by Stanley
Williams
created the first dF =Ldi
=Mdq
memristor φ pediain.com
What is a MEMRISTOR
Memristor is really a MEMory ResISTOR
Memristor can be defined as a two terminal device which shows the relation between magnetic flux and charge memristor symbol
pediain.com
Memristor Theory
Or
Or
pediain.com
Memristor and Resistor
• The way resistor has resistance , memristor has memristance. • Same unit –ohm.
• Memristance can be switched to different states.
• Memristor has non linear v-i plot.
pediain.com
Memristor features
• resistance depends on magnitude, polarity and time application of voltage.
• Save its electronic state when current is turned off.
• “Remember” how much current has passed through it. pediain.com
Physical analogy for a memristor
• Resistor is analogous to a pipe of fixed diameter through which water is flowing
• Water(charge q), input pressure(voltage v), rate of flow of water(current i).
• Resitance depends on diameter.
• Memristor is analogous to a special kind of pipe that expands or shrinks when water flows through it.
• The pipe is directive in nature.
• If water pressure is turned off, pipe will retain its most recent diameter, until water is turned back on. pediain.com Physical analogy for a memristor
Memristor
Pipe
Charge
Water
Conductance
Cross sectional area
Potential
Pressure
When water flows in one direction the diameter increases (resistance decreases) When water flows in opposite direction the diameter decreases (resistance increases) pediain.com
Why memristor a fundamental element
• Can not be duplicated by R,C,L.
• Peculiar behaviour- carries memory of past.
• Duplication requires alot of
References: Chua (1971) "Memristive Devices and Systems" in the Proceedings of the IEEE by Leon Chua and his student Sung Mo Kang (1976) "The missing (may2008) Sally Adee (may 2008) IEEE Spectrum - How We Found the Missing Memristor, by R. Stanley Williams (dec 2008) pediain.com