US 11,783,895 B2
Power off recovery in cross-point memory with threshold switching selectors
Neil Robertson, Palo Alto, CA (US); Michael Grobis, Campbell, CA (US); and Ward Parkinson, Boise, ID (US)
Assigned to SanDisk Technologies LLC, Addison, TX (US)
Filed by SanDisk Technologies LLC, Addison, TX (US)
Filed on Sep. 13, 2022, as Appl. No. 17/943,550.
Application 17/943,550 is a continuation of application No. 17/090,438, filed on Nov. 5, 2020, granted, now 11,501,831.
Prior Publication US 2023/0005539 A1, Jan. 5, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G11C 11/00 (2006.01); G11C 13/00 (2006.01)
CPC G11C 13/0069 (2013.01) [G11C 13/003 (2013.01); G11C 13/004 (2013.01); G11C 13/0004 (2013.01); G11C 13/0038 (2013.01); G11C 13/0061 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a control circuit configured to connect to a plurality of arrays each including a plurality of non-volatile memory cells, each memory cell comprising a programmable resistive element connected in series with a threshold switching selector, the threshold switching selector configured to become conductive in response to application of a voltage level exceeding a corresponding threshold voltage that increases as a function of time since last becoming conductive, the control circuit is configured to:
power up a first one or more of the plurality of arrays for an access operation;
subsequent to powering up the first one or more arrays, perform the access operation for one or more of the memory cells of the first one or more arrays;
power down the first one or more arrays;
subsequent to powering up the first one or more arrays to perform an access operation following a preceding powering down of the first one or more arrays storing data content, and prior to performing the access operation, determine a time value for a time between powering up the first one or more arrays to perform an access operation and the preceding powering down of the first one or more arrays; and
in response to determining that the time value for the time between powering up the first one or more arrays to perform an access operation and the preceding powering down of the first one or more arrays exceeding a threshold value, reload the stored data content to the first one or more arrays from another one or more of the plurality of arrays in which the data content is stored redundantly.