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US 10,762,971 B2Granted
Responding to power loss
AssigneeMicron Technology, Inc.
InventorRainer Bonitz
Life of this patent
Estimating the term…
Abstract
Apparatus including an array of volatile memory cells and a differential storage device configured to receive information indicative of a data value stored in a particular memory cell of the array of volatile memory cells and having a first non-volatile memory cell connected between a first isolation gate and a voltage node configured to receive a first voltage level and a second non-volatile memory cell connected between a second isolation gate and the voltage node, wherein a gate of the second non-volatile memory cell is connected to a gate of the first non-volatile memory cell. The apparatus further logic responsive to an indication of a loss of power to the apparatus and the information indicative of the data value stored in the particular memory cell.
Claims20
An apparatus, comprising:
- an array of volatile memory cells;
- and
- a differential storage device configured to receive information indicative of a data value stored in a particular memory cell of the array of volatile memory cells, the differential storage device comprising:
- a first non-volatile memory cell connected between a first isolation gate and a voltage node configured to receive a first voltage level;
- a second non-volatile memory cell connected between a second isolation gate and the voltage node, wherein a gate of the second non-volatile memory cell is connected to a gate of the first non-volatile memory cell;
- and
- logic responsive to an indication of a loss of power to the apparatus and the information indicative of the data value stored in the particular memory cell;
- wherein the logic is configured to cause the first isolation gate and the second isolation gate to be deactivated in response to the indication of a loss of power to the apparatus having a particular logic level regardless of a logic level of the information indicative of the data value stored in the particular memory cell;
- wherein the logic is further configured to cause a second voltage level higher than the first voltage level to be applied to gates of the first non-volatile memory cell and the second non-volatile memory cell in response to the indication of a loss of power to the apparatus having its particular logic level regardless of the logic level of the information indicative of the data value stored in the particular memory cell;
- wherein the logic is further configured to cause a third voltage level, less than the second voltage level and greater than the first voltage level, to be applied to a node between the first non-volatile memory cell and the first isolation gate in response to the indication of a loss of power to the apparatus having its particular logic level and the information indicative of the data value stored in the particular memory cell having a particular logic level;
- and
- wherein the logic is further configured to cause the first voltage level to be applied to the node between the first non-volatile memory cell and the first isolation gate in response to the indication of a loss of power to the apparatus having its particular logic level and the information indicative of the data value stored in the particular memory cell having a logic level different than its particular logic level.
9 more elements
An apparatus, comprising:
- an array of volatile memory cells;
- and
- a differential storage device configured to receive information indicative of a data value stored in a particular memory cell of the array of volatile memory cells, the differential storage device comprising:
- a first level shifter for generating a first control signal and a second control signal having complementary logic levels responsive to information indicative of a voltage level of a supply voltage relative to a threshold, and to the information indicative of the data value stored in the particular memory cell, wherein the supply voltage is used for access of the array of volatile memory cells;
- a second level shifter for generating a third control signal and a fourth control signal having complementary logic levels responsive to the information indicative of the voltage level of the supply voltage relative to the threshold, and to the information indicative of the data value stored in the particular memory cell;
- a third level shifter for generating a fifth control signal and a sixth control signal having complementary logic levels responsive to the information indicative of the voltage level of the supply voltage relative to the threshold;
- a first non-volatile memory cell connected in series between a first node and a first voltage node;
- a second non-volatile memory cell connected in series between a second node and the first voltage node;
- a first isolation gate connected in series between a third node and the first node;
- and
- a second isolation gate connected in series between a fourth node and the second node;
- wherein, when the information indicative of the voltage level of the supply voltage relative to the threshold indicates that the voltage level of the supply voltage is greater than the threshold, the first control signal, the third control signal and the fifth control signal each have a first logic level, and the second control signal, the fourth control signal and the sixth control signal each have a second logic level different than the first logic level;
- wherein, when the information indicative of the voltage level of the supply voltage relative to the threshold indicates that the voltage level of the supply voltage is less than the threshold, and the information indicative of the data value stored in the particular memory cell is indicative of the data value having a particular logic level, the second control signal, the third control signal and the sixth control signal each have the first logic level, and the first control signal, the fourth control signal and the fifth control signal each have the second logic level;
- wherein, when the information indicative of the voltage level of the supply voltage relative to the threshold indicates that the voltage level of the supply voltage is less than the threshold, and the information indicative of the data value stored in the particular memory cell is indicative of the data value having a different logic level, the first control signal, the fourth control signal and the sixth control signal each have the first logic level, and the second control signal, the third control signal and the fifth control signal each have the second logic level;
- wherein the first isolation gate and the second isolation gate are configured to receive a gate voltage having a first voltage level when either the first control signal or the third control signal has the second logic level, and to receive a gate voltage having a second voltage level higher than the first voltage level when both the first control signal and the third control signal have the first logic level;
- wherein the first non-volatile memory cell and the second non-volatile memory cell are configured to receive a gate voltage having a third voltage level between the first voltage level and the second voltage level when the fifth control signal has the first logic level, and to receive a gate voltage having a fourth voltage level higher than the second voltage level when the sixth control signal has the first logic level;
- wherein the first node is configured to receive a fifth voltage level between the first voltage level and the third voltage level when the second control signal has the first logic level;
- and
- wherein the second node is configured to receive the fifth voltage level when the fourth control signal has the first logic level.
16 more elements
A method of operating an apparatus, comprising:
- in response to powering up the apparatus, determining if a power loss to the apparatus was indicated;
- and
- if a power loss to the apparatus was indicated:
- obtaining information indicative of a data value of a differential storage device of the apparatus in response to a difference in current flow through each non-volatile memory cell of a pair of gate-connected non-volatile memory cells of the differential storage device;
- and
- programming a corresponding memory cell of an array of volatile memory cells of the apparatus responsive to the information indicative of the data value of the differential storage device.
3 more elements
A method of operating an apparatus, comprising:
- in response to powering up the apparatus, determining if a power loss to the apparatus was indicated;
- and
- if a power loss to the apparatus was indicated:
- obtaining information indicative of a data value of a first differential storage device of the apparatus;
- and
- programming a corresponding memory cell of an array of volatile memory cells of the apparatus responsive to the information indicative of the data value of the first differential storage device;
- wherein determining if a power loss to the apparatus was indicated comprises determining a data value of a second differential storage device of the apparatus;
- and
- wherein the second differential storage device comprises a first non-volatile memory cell having a first source/drain connected to a first voltage node configured to receive a first voltage level and a second source/drain selectively connected to a second voltage node configured to receive a second voltage level greater than the first voltage level, and a second non-volatile memory cell having a first source/drain connected to the first voltage node and a second source/drain selectively connected to the second voltage node, wherein a gate of the second non-volatile memory cell is connected to a gate of the first non-volatile memory cell, and wherein determining the data value of the second differential storage device comprises:
- connecting the second source/drain of the first non-volatile memory cell and the second source/drain of the second non-volatile memory cell to the second voltage node;
- selectively isolating either the second source/drain of the first non-volatile memory cell or the second source/drain of the second non-volatile memory cell in response to a difference in current flow through the first non-volatile memory cell and the second non-volatile memory cell;
- and
- determining the data value of the second differential storage device in response to voltage levels developed at the second source/drain of the first non-volatile memory cell and the second source/drain of the second non-volatile memory cell.
10 more elements
A method of operating an apparatus, comprising:
- in response to powering up the apparatus, determining if a power loss to the apparatus was indicated;
- and
- if a power loss to the apparatus was indicated;
- obtaining information indicative of a data value of a first differential storage device of the apparatus;
- and
- programming a corresponding memory cell of an array of volatile memory cells of the apparatus responsive to the information indicative of the data value of the first differential storage device;
- wherein powering up the apparatus comprises powering up the apparatus for a particular occurrence of a plurality of occurrences of powering up the apparatus, the method further comprising:
- prior to powering up the apparatus for the particular occurrence, and subsequent to powering up the apparatus for an immediately prior occurrence of the plurality of occurrences, selectively programming one non-volatile memory cell of a pair of gate-connected non-volatile memory cells of a second differential storage device of the apparatus to indicate a power loss to the apparatus.
5 more elements
A method of operating an apparatus, comprising:
- in response to powering up the apparatus, determining if a power loss to the apparatus was indicated;
- and
- if a power loss to the apparatus was indicated:
- obtaining information indicative of a data value of a differential storage device of the apparatus;
- and
- programming a corresponding memory cell of an array of volatile memory cells of the apparatus responsive to the information indicative of the data value of the differential storage device;
- wherein the differential storage device comprises a first non-volatile memory cell having a first source/drain connected to a first voltage node configured to receive a first voltage level and a second source/drain selectively connected to a second voltage node configured to receive a second voltage level greater than the first voltage level, and a second non-volatile memory cell having a first source/drain connected to the first voltage node and a second source/drain selectively connected to the second voltage node, wherein a gate of the second non-volatile memory cell is connected to a gate of the first non-volatile memory cell, and wherein obtaining the information indicative of the data value of the differential storage device comprises:
- connecting the second source/drain of the first non-volatile memory cell and the second source/drain of the second non-volatile memory cell to the second voltage node;
- selectively isolating either the second source/drain of the first non-volatile memory cell or the second source/drain of the second non-volatile memory cell in response to a difference in current flow through the first non-volatile memory cell and through the second non-volatile memory cell;
- and
- determining the data value of the differential storage device in response to voltage levels developed at the second source/drain of the first non-volatile memory cell and the second source/drain of the second non-volatile memory cell.
8 more elements
Dependencies are inferred from the claim text.