Preservation circuit and methods to maintain values representing data in one or more layers of memory

摘要

Circuitry and methods for restoring data in memory are disclosed. The memory may include at least one layer of a non-volatile two-terminal cross-point array that includes a plurality of two-terminal memory elements that store data as a plurality of conductivity profiles and retain stored data in the absence of power. Over a period of time, logic values indicative of the stored data may drift such that if the logic values are not restored, the stored data may become corrupted. At least a portion of each memory may have data rewritten or restored by circuitry electrically coupled with the memory. Other circuitry may be used to determine a schedule for performing restore operations to the memory and the restore operations may be triggered by an internal or an external signal or event. The circuitry may be positioned in a logic layer and the memory may be fabricated over the logic layer.

主权项

1. A memory device, comprising:
a plurality of re-writeable non-volatile two-terminal memory devices in electrical communication with a memory bus, each memory device including at least one memory layer including a plurality of memory elements having exactly two terminals and configured in at least one two-terminal cross-point array, each memory element is configured to store data associated with resistance values, and a silicon substrate including circuitry fabricated on a logic layer of the silicon substrate and at least a portion of the circuitry electrically coupled with the at least one two-terminal cross-point array and configured to perform data operations on one or more of the plurality of memory elements, wherein the at least one memory layer is in contact with and is fabricated directly above the silicon substrate; at least one preservation circuit in electrical communication with the at least one two-terminal cross-point array and operative to perform preservation operations on one or more of the plurality of memory elements and configured to, in response to a trigger signal, restore the resistance values to represent the data; and at least one trigger circuit electrically coupled with the at least one preservation circuit and configured to detect a triggering event and generate the trigger signal.