I was baffled when I first read of memristors in the October 1-15 edition of EE Time Asia. Conventional wisdom (and many years of studying electronics) have conditioned electrical engineers to think that there are only 3 passive circuit elements, i.e. resistors, inductors and capacitors. Naturally, my curiosity was piqued when I read this feature article on memristors.
Historically, the memristor was postulated in 1971, and named such as an abbreviation for "memory resistor". Technically, a memristor is a passive circuit element that relates flux to charge in the same way resistors relate voltage to current, capacitors relate voltage to charge and inductors relate flux to current.
According to Wolfgang Porod, an electrical engineering professor at Notre Dame University, a resistor relates voltage to current and the memristor relates flux to charge. However, if you sum up flux over time, it becomes a voltage, and if you sum up charge over time it becomes a current. So a device that relates flux to charge, like a memristor, will over time relate voltage to current like a variable resistor, whose resistance changes its value depending on how much and in which direction current has flowed through it.
The nost immediate application for memristors is in the area of memory. As a memristor's resistance changes as current flows through it, it is possible to build an entirely new kind of memory using crossbar switches. Zeroes and Ones can be determined based on the difference in resistivity of each point of the array.
Once this technique has been perfected, it will be possible to produce high-density memory arrays cheaply. Once it has reached critical mass, it could possibly sound the death knell for current solid state memory technologies e.g. NOR and NAND RAM.
Historically, the memristor was postulated in 1971, and named such as an abbreviation for "memory resistor". Technically, a memristor is a passive circuit element that relates flux to charge in the same way resistors relate voltage to current, capacitors relate voltage to charge and inductors relate flux to current.
According to Wolfgang Porod, an electrical engineering professor at Notre Dame University, a resistor relates voltage to current and the memristor relates flux to charge. However, if you sum up flux over time, it becomes a voltage, and if you sum up charge over time it becomes a current. So a device that relates flux to charge, like a memristor, will over time relate voltage to current like a variable resistor, whose resistance changes its value depending on how much and in which direction current has flowed through it.
The nost immediate application for memristors is in the area of memory. As a memristor's resistance changes as current flows through it, it is possible to build an entirely new kind of memory using crossbar switches. Zeroes and Ones can be determined based on the difference in resistivity of each point of the array.
Once this technique has been perfected, it will be possible to produce high-density memory arrays cheaply. Once it has reached critical mass, it could possibly sound the death knell for current solid state memory technologies e.g. NOR and NAND RAM.
