Measurement system for a preliminary characterization of flash memory cells for multilevel applications

In this work a low-cost measurement system suitable for analog characterization of standard Flash memory cells is presented. Our aim, with this system, is to investigate the possibility of using standard cells for multilevel storage, to increase the bit density of conventional memory devices. Preliminary investigation was carried out by using a measurement system based on stand-alone instrumentation linked to a controller via IEEE 488 bus. The preliminary characterization results of the Texas Instruments TMS29FO40 4-Mbit Flash Memory show that it is feasible to store and retrieve information with four levels of injection charge in a single cell. Currently, a first multilevel test chip is under development. At the same time, a new measurement system, specifically suited to debug and test this special device, is under implementation.