1. MEMRISTOR TECHNOLOGY

2. Memristor Technology
INTRODUCTION:
Memristor is a computer component that offers both memory and logic functions in one simple
package. A ‘mem’ memory, ristor ‘resistor’ is a passive two-terminal circuit element that
maintains a functional relationship between the time integrals of current and voltage. It has the
potential to transform the semiconductor industry, enabling smaller, faster, cheaper chips and
computers.
"In 2014 possibly, or certainly by 2015, we will have a competitor for DRAM and then we'll
replace SRAM," said Stan Williams Senior Fellow of HP.
Working:
Memristor is an electrically switchable semiconductor thin film sandwiched between two metals.
The internal state variable determines the length of doped region with low resistance against un-
doped region with high resistivity. By passing current from memristor in one direction will
increase the resistance while changing the direction of the applied current will decrease its
resistance. On the other hand, it is clear that in this element, passing current in one direction for
longer period of time will change the resistance of the memristor.
Fig. Structure of the memristor reported by HP researchers and its equivalent circuit model.
As a result, memristor is nothing else than the analog variable resistor which its resistance can
be adjusted by changing the direction and duration of the applied voltage or current. Therefore,
memristor can be used as a storage device in which analog values can be stored as impedance
instead of voltage.

3. Features of memristor:
a) Simple Structure:
The structure is a well ordered, periodic and simple, this is the
reason we get nanoscale resolution. Bits which are transferred to
DRAM, USB’s etc are in microsecond, but if we have a memristor it will transfer bits in
nanoseconds.
b) Fast, low power and cheap:
Memristors works hundred times faster than flash and uses a hundred times less
energy. Also, memristors don't need exotic materials and don't need low temperatures to
work.
c) Nonvolatile memory:
It has a nonvolatile memory, means it does not loss data whenever the computer boots
up. Non-volatile state can be accomplished by memristor because their state is encoded
by impendence (physically) not voltage.
Applications of memristor:
a) Crossbar latches as transistor replacements:
When solid state memristor is combined into devices called crossbar latches which
would replace transistors in future computers taking up a much smaller area. They could
replace transistors in some components of logic gates and memory cells in digital
electronic system.
b) Low power and remote sensing application:
Low power is application software; it is easy to collect data on dangerous areas e.g.
Antarctica.
There are two types of remote sensing:
Passive remote sensing: It is detected
through radiations which they emit and reflect
by some object. Sunlight is the common source
of radiation.
Active remote sensing: Real life example of
active remote sensing is infrared and
photography Radar is another example.
How low power and remote sensing
application made:
1. They are made by combination of
capacitors and inductors circuits they allow
storage charge for memristors.
2. It can allow nanoscale low power memory.
3. Distributed state storage of charge as more extension of ram capabilities.
4. They are not real in terms of time to market.

4. c) Uses of memristor in field of medical:
Researchers in South Korea made a digital memory that
can store data without constant power. Memories could find
applications in electronic paper for more comfortable
reading and in wearable computers, which could be used in
medical monitoring and treatments. It can bends easily round a pencil-sized rod.
d) Future of flash drives:
Memristor is used as a cheaper and faster alternative to
flash memory.
They are replacing flash memories. Non-volatile memory is
build with memristors, meaning that unlike DRAM they’ll
retain information even when you turn off the power.
Memristor runs 10 times faster while using 10 times less
power than flash memory. Memristors could eventually store data and process data.
Advantages of Memristor Technology:
a) Memristor allows for quicker boot up since information is not lost when the device is
turned off.
b) Memristors are faster, cheaper and smaller than RAM and flash memories.
c) It has more storage capacity than flash memories, DRAM and RAM.
d) It uses less energy and produces less heat.
e) It does not lose information when turned off because of its non-volatile nature.
f) RAM and flash memories use only 0 and 1 while memristor can use anything between 0
and 1 (0.3, 0.8, 0.5, etc.)
Disadvantages of Memristor technology:
a) If a computer is infected with a virus, the memristors may cause the computer to keep
rebooting with the same problem because the memory will not be lost after reboot.
b) Memristors ability to learn from patterns, if a bad pattern is present at an early stage, the
computer's problem could grow worse and worse at a rapid rate.
c) They store data can never be deleted.
Conclusion:
It is possible to obtain the same function with fewer components, making the circuit itself less
expensive and significantly decrease its power consumption. In fact, it can be hoped to combine
memristor with traditional circuit design element to produce a new device that does a new
computation. Thus the memristor forms a bridge between present technology and future
technology.