Optimized threshold search in analog memory cells
AssigneeApple Inc.
InventorsMicha Anholt, Naftali Sommer
Life of this patent
Estimating the term…
Abstract
A method includes storing data in a group of analog memory cells. The memory cells in the group are read using first read thresholds to produce first readout results, and re-read using second read thresholds to produce second readout results. Third read thresholds, which include at least one of the first read thresholds and at least one of the second read thresholds, are defined. Readout performance of the first, second and third read thresholds is evaluated based on the first and second readout results. The first, second or third read thresholds are selected based on the evaluated readout performance, and data recovery is performed using the selected read thresholds.
Claims28
A method, comprising:
- storing data in a group of analog memory cells;
- reading the memory cells in the group using first read thresholds, to produce first readout results;
- re-reading the memory cells in the group using second read thresholds, to produce second readout results;
- defining third read thresholds, which comprise at least one of the first read thresholds and at least one of the second read thresholds;
- evaluating readout performance of the first, second and third read thresholds based on the first and second readout results;
- and
- selecting the first, second or third read thresholds based on the evaluated readout performance, and performing data recovery using the selected read thresholds.
Apparatus, comprising:
- a memory, comprising multiple analog memory cells;
- and
- storage circuitry, which is configured to store data in a group of the analog memory cells, to read the memory cells in the group using first read thresholds so as to produce first readout results, to re-read the memory cells in the group using second read thresholds so as to produce second readout results, to define third read thresholds that comprise at least one of the first read thresholds and at least one of the second read thresholds, to evaluate readout performance of the first, second and third read thresholds based on the first and second readout results, to select the first, second or third read thresholds based on the evaluated readout performance, and to perform data recovery using the selected read thresholds.
Apparatus, comprising:
- an interface, which is configured to communicate with a memory that includes multiple analog memory cells;
- and
- storage circuitry, which is configured to store data in a group of the analog memory cells, to read the memory cells in the group using first read thresholds so as to produce first readout results, to re-read the memory cells in the group using second read thresholds so as to produce second readout results, to define third read thresholds that comprise at least one of the first read thresholds and at least one of the second read thresholds, to evaluate readout performance of the first, second and third read thresholds based on the first and second readout results, to select the first, second or third read thresholds based on the evaluated readout performance, and to perform data recovery using the selected read thresholds.
Dependencies are inferred from the claim text.