A µ-controller-based system for interfacing selector-less RRAM crossbar arrays

Selectorless crossbar arrays of resistive random access memory (RRAM), also known as memristors, conduct large sneak currents during operation, which can significantly corrupt the accuracy of cross-point analog resistance (Mt) measurements. In order to mitigate this issue, we have designed, built, and tested a memristor characterization and testing (mCAT) instrument that forces redistribution of sneak currents within the crossbar array, dramatically increasing Mt measurement accuracy. We calibrated the mCAT using a custom-made 32 × 32 discrete resistive crossbar array, and subsequently demonstrated its functionality on solid-state TiO2-x RRAM arrays, on wafer and packaged, of the same size. Our platform can measure standalone Mt in the range of 1 kΩ to 1 MΩ with <1% error. For our custom resistive crossbar, 90% of devices of the same resistance range were measured with <10% error. The platform's limitations have been quantified using large-scale nonideal crossbar simulations