CYCLING TO MITIGATE IMPRINT IN FERROELECTRIC MEMORIES

摘要

One embodiment of the present invention relates to a method for reducing the imprint of a ferroelectric memory cell. The method comprises storing a memory data state in the ferroelectric memory cell. An event will trigger the evaluation of signal margin on a memory cell. If the memory cell is identified to have a weak signal, the memory cell is exercised. Exercising comprises either performing one or more data read/re-write events or performing one or more simulated data read and data write events of an alternating high data state and a low data state to the memory cell associated with the weak data bit. Both the lifetime retention testing and the memory data state exercising are performed in the background of normal memory operation. Other methods and circuits are also disclosed.