Back to results
US 10,474,525 B2Granted
Soft bit techniques for a data storage device
AssigneeSanDisk Technologies LLC
InventorsEran Sharon, Ariel Navon, Idan Alrod, Alexander Bazarsky
Life of this patent
Estimating the term…
Abstract
A data storage device includes a memory, a first module, and a second module. The first module is configured to sense data stored at the memory to generate a first set of soft bits having a first number of bits. The second module is configured to perform an operation using the first set of soft bits to generate a second set of soft bits having a second number of bits that is less than the first number of bits. In an illustrative implementation, the second set of soft bits is used in connection with a three-stage decoding process to decode a set of hard bits that represents the data.
Claims26
A data storage device comprising:
- a controller;
- and
- a memory device including
- a memory;
- a first circuit configured to
- determine one or more delta values as a function of a compression rate, each delta value indicating a difference between a hard bit sensing threshold and a soft bit sensing threshold, and
- sense data stored at the memory based on the one or more delta values to generate a first set of soft bits having a first number of bits;
- and
- a second circuit configured to
- perform an operation using the first set of soft bits to generate a second set of soft bits having a second number of bits that is less than the first number of bits, the first number of bits and the second number of bits corresponding to the compression rate;
- and
- provide the second set of soft bits to the controller,
- wherein the second circuit includes a compressed soft bit (CSB) circuitry configured to compress the first set of soft bits to generate the second set of soft bits in accordance with a lossy compression scheme, and wherein the lossy compression scheme including a bitwise AND operation using a first bit of a subset of the first set of soft bits and a second bit of the subset of the first set of soft bits to generate a third bit of the second set of soft bits.
10 more elements
A method comprising:
- in a data storage device that includes a controller coupled to a memory device, wherein the memory device includes a memory, performing by the memory device:
- determining one or more delta values as a function of a compression rate, each delta value indicating a difference between a hard bit sensing threshold and a soft bit sensing threshold;
- in response to receiving a read command from the controller, sensing data stored at the memory based on the one or more delta values to generate a first set of soft bits having a first bit count;
- performing an operation using the first set of soft bits to generate a second set of soft bits having a second bit count that is less than the first bit count, wherein the first bit count and the second bit count correspond to the compression rate, wherein performing the operation includes compressing the first set of soft bits to generate the second set of soft bits in accordance with a lossy compression scheme, and wherein the lossy compression scheme including a bitwise AND operation using a first bit of a subset of the first set of soft bits and a second bit of the subset of the first set of soft bits to generate a third bit of the second set of soft bits;
- and
- providing the second set of soft bits to the controller.
3 more elements
An apparatus comprising:
- means for storing data;
- means for determining one or more delta values as a function of a compression rate, each delta value indicating a difference between a hard bit sensing threshold and a soft bit sensing threshold;
- means for sensing the data based on the one or more delta values to generate a first set of soft bits having a first number of bits;
- means for performing an operation using the first set of soft bits to generate a second set of soft bits having a second number of bits that is less than the first number of bits, wherein the first number of bits and the second number of bits correspond to the compression rate, wherein the means for performing the operation is configured to compress the first set of soft bits to generate the second set of soft bits based on a lossy compression scheme, and wherein the lossy compression scheme including a bitwise AND operation using a first bit of a subset of the first set of soft bits and a second bit of the subset of the first set of soft bits to generate a third bit of the second set of soft bits;
- and
- means for providing the second set of soft bits to the controller.
3 more elements
Dependencies are inferred from the claim text.