Patent ID: 6795330
Filing Date: 2004-09-21
Classification: G11C

Abstract:
A method of reading and restoring data stored in a ferroelectric memory cell, which cell comprises:a first transistor and first ferroelectric capacitor connected, in series with each other, between a first bitline and an auxiliary line; a second transistor and second ferroelectric capacitor connected, in series with each other, between a second bitline and the auxiliary line; said first and second transistors having respective control terminals connected to a common wordline; the reading method comprising the following steps: precharging said first and second capacitors; applying a read pulse to said cell such that the state of said first capacitor is changed; reading said cell by a sensing means; and restoring said first capacitor to an initial state; the reading method being characterized in that it further comprises the steps of: changing the state of said second capacitor during said step of restoring said first capacitor, and further restoring said second capacitor to an initial state, such that the voltages being applied to said transistors during any of said steps are lower than a voltage reference of said cell.