Patent ReferencesMethod for reading and restoring data in a data storage element Memory cell that can store data nonvolatily using a ferroelectric capacitor, and a semiconductor memory device including such a memory cell Ferroelectric memory device and method for driving it Patent #: 6118688 InventorsAssigneeApplicationNo. 10281075 filed on 10/24/2002US Classes:365/145, Ferroelectric365/149CapacitorsExaminersPrimary: Lebentritt, Michael S.Assistant: Le, Thong Attorney, Agent or FirmForeign Patent References
International ClassG11C011/22AbstractA method of sensing a ferroelectric non-volatile information storage unit comprising two ferroelectric storage capacitors in mutually opposite polarization states, and a sensing circuit for actuating the method. The method comprises the steps of: making a voltage applied across the two storage capacitors substantially zero; starting from this condition, progressively increasing the voltage applied thereacross by supplying a prescribed current, until a first one of the two storage capacitors approaches a condition of polarization state reversal, thereby the voltage applied across said first storage capacitor starts to decrease with respect to the voltage applied across the second storage capacitor; and amplifying a voltage difference between the voltages applied across the two storage capacitors by making the voltage applied across the first storage capacitor substantially zero and the voltage applied across the second storage capacitor substantially equal to a non-zero voltage corresponding to a logic state opposite to a logic state corresponding to the zero voltage. | |