DATA READING METHOD AND DATA WRITING METHOD FOR EXTENDING AN OPERATING MARGIN IN A READING OPERATION IN SEMICONDUCTOR MEMORY DEVICE USING FERROELECTRIC MEMORY, AND SEMICONDUCTOR MEMORY DEVICE FOR CARRYING OUT DATA READING METHOD OR THE DATA WRITING METHOD

摘要

PURPOSE: A data reading method, a data writing method, and a semiconductor memory device are provided to reduce effectively an error rate by erasing a variation of a high level side. CONSTITUTION: A first reading pulse is applied to a memory cell to generate a first signal corresponding to stored data. Reference signal generating data corresponding to a signal on a high level side is written to the memory cell. A second reading pulse is applied to the memory cell to generate a second signal corresponding to the reference signal generating data. A reference signal is generated on a basis of the second signal. The first signal is compared with the reference signal. The stored data of the memory cell is determined.