CIRCUIT AND METHOD FOR READING A RESISTIVE SWITCHING DEVICE IN AN ARRAY

摘要

A read circuit for sensing a resistance state of a resistive switching device in a crosspoint array utilizes a transimpedance equipotential preamplifier connected to a selected column line of the resistive switching device in the array. The equipotential preamplifier delivers a sense current while maintaining the selected column line at a reference voltage near a biasing voltage applied to unselected row lines of the array. A reference resistor is selectively connected to the equipotential preamplifier for setting a reference current, wherein the equipotential preamplifier is set to produce a preamplifier output voltage having a magnitude depending on whether the sense current is smaller or greater than the reference current. A voltage comparator is connected to the equipotential preamplifier to compare the preamplifier output voltage with a setup reference voltage and generate a comparator output voltage indicative of the resistance state of the resistive switching device.