Descoberta de outro bloco fundamental dos circuitos eléctricos

Nova descoberta pode substituir memórias DRAM, diz HP
De acordo com a empresa, a descoberta do elemento “Memristor” pode revolucionar a maneira pela qual os dados são armazenados.

Por Redação do COMPUTERWORLD
30 de abril de 2008 - 16h16página 1 de 1Recursos: Imprimir Texto Enviar por e-mail Comentar Reportar Erros Cadastrar Feeds Ampliar texto Reduzir textoBookmark:
Os laboratórios de pesquisa da HP conseguiram provar a existência do quarto elemento fundamental de um circuito em engenharia elétrica - além do capacitor, resistor e indutor. Antes da descoberta, a existência do elemento chamado “Memristor” era considerada uma possibilidade teórica.

De acordo com a HP, o elemento pode revolucionar a maneira pela qual os circuitos armazenam informações. Na prática, diz a empresa, as memórias não perderiam os dados, consumiriam muito menos energia e estaria eliminada a necessidade de reiniciá-las.

Em comunicado oficial, a HP garante: “[os chips produzidos com a tecnologia] associariam informações de maneira semelhante ao processo do cérebro humano”.

> Nova memória da IBM promete armazenar 500 vezes mais


O estudo foi publicado na revista Nature por quatro pesquisadores do laboratório da HP. Por meio de um modelo matemático, a equipe liderada por R. Stanley Williams deu um exemplo do “memristor” (palavra formada pela combinação de “memory resistor”), que tem a capacidade de reter a história da informação que adquiriu.

“Descobrir algo novo e tão fundamental no maduro campo da engenharia elétrica é uma grande surpresa, especialmente por ser uma descoberta que tem implicações significativas para o futuro da ciência computacional”, disse Williams em comunicado oficial.

A HP afirma que, a partir do "memristor", novos tipos de memórias poderiam ser desenvolvidos para substituir a DRAM (dynamic random access memory). Ao contrário da DRAM, que perde a informação quando não têm energia e precisam reiniciar, a nova memória não precisaria disso.

Engineers find 'missing link' of electronics
18:00 30 April 2008
NewScientist.com news service



Nanoscale circuits based on molecules used in sunscreen lotion have led to the discovery of the "missing link" of electronics engineering – a previously mythical device known as a "memristor".
First predicted in 1971, the memristor could help develop denser memory chips or even electronic circuits that mimic the synapses of the human brain, says Stan Williams who made the discovery with colleagues at Hewlett-Packard's lab in Palo Alto, California.
Since electronics was developed, engineers have made circuits using combinations of three basic elements – resistors, capacitors and inductors.
But in 1971, a young circuit designer called Leon Chua at the University of California, Berkeley, realised something was missing. He was toying with the non-linear mathematics that describes how the four variables in a circuit – voltage, current, charge and flux – behave in the three basic elements.
'Sheer genius'The three building blocks each relate two of the four electronic properties of circuits, creating a chain linking charge to flux via voltage and current. But his calculations showed there should be a fourth device to directly link flux and charge.
"This was a stroke of absolute, sheer genius by Chua," says Williams. "He then worked through some complex mathematics and saw that such a device would have an unusual property: the ability to remember its past history."
Chua showed that his predicted device could remember the last voltage applied to it, and how long it had been applied. He dubbed the property "memristance" but the memristor was quietly forgotten because it was unclear how it could ever be built.
Sunblock circuitsBut Williams' team has now done just that, using nanoscale circuits including molecules of the active ingredient of sunscreen – titanium dioxide.
Such circuits are used to try and use small clumps of molecules to store the binary 0s and 1s of charge to work as computer memory.
However, these efforts have been dogged by bizarre electronic effects, says Williams, who has now worked out the reason. His titanium dioxide works as a memoristor – the mythical device has been found.
Chua, now close to retirement, is thrilled at the finding. "This seminal work presents the first example of the memristor I postulated in 1971," he told New Scientist. "We can now expect many new unconventional applications, including super-dense memories and brain-like computing chips."
Electronic synapseThe way memristors handle current and voltage is startlingly similar to the way synapses between brain cells do, says Chua. Both build up voltage to a threshold before firing and letting a current pass.
Williams agrees. "The memristor equations do a very good job of modelling the known behaviour of synapses," he says.
He is now working to find which materials make the best memristors, and why it has only been seen so far in nanoscale devices. Williams then wants to attempt to build memristor-based memories, which will store information as resistance values and therefore need no power to hold on to the data.
Journal reference: Nature (DOI: 10.1038/nature06932)


http://technology.newscientist.com/article/dn13812-engineers-find-missing-link-of-electronics.html

Como um protector pode conter o material que se ambicionava ter o comportamento previsto teoricamente pelo Sr. Chua.
http://en.wikipedia.org/wiki/Memristor

"...um material opaco que reflete a luz (como o dióxido de titânio, o óxido de zinco)..."
http://pt.wikipedia.org/wiki/Protetor_solar
http://www.ideiasambientais.com.pt/nanotecnologia.html