Patents by Inventor Haobo Wang

Haobo Wang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11769556
    Abstract: Embodiments provide a scheme for estimating an optimal read threshold voltage using a deep neural network (DNN) with a reduced number of processing. A controller includes a combined neural network, which receives first and second cumulative distribution function (CDF) values, each CDF value corresponding to a program voltage (PV) level associated with a read operation on the cells. The combined neural network generates first and second connection vectors based on the first and second CDF values and first weight values, and estimates an optimal read threshold voltage based on the first and second connection vectors and second weight values.
    Type: Grant
    Filed: July 27, 2021
    Date of Patent: September 26, 2023
    Assignee: SK hynix Inc.
    Inventors: Haobo Wang, Aman Bhatia, Fan Zhang
  • Publication number: 20230176765
    Abstract: Devices, systems and methods for improving performance of a memory device are described. An example method includes obtaining a plurality of samples corresponding to a probability distribution for each of a plurality of cell voltage distributions of the memory device, each of the plurality of cell voltage distributions corresponding to a read voltage, determining, based on the samples obtained for the plurality of cell voltage distributions, a number of first deep neural networks (DNNs), estimating, for each of the first DNNs, one or more parameters of the corresponding probability distribution based on the plurality of samples, training, based on the samples and the corresponding one or more parameters, each of the first DNNs, and training, based on the samples and the one or more parameters from each of the first DNNs, a second DNN to enable generation of an updated read voltage value for retrieving information from the memory device.
    Type: Application
    Filed: December 7, 2021
    Publication date: June 8, 2023
    Inventors: Haobo WANG, Aman BHATIA, Fan ZHANG
  • Publication number: 20230071837
    Abstract: Devices, systems and methods for improving performance of a memory device are described. An example method includes receiving one or more parameters associated with a plurality of previous read operations on a page of the memory device, wherein the previous read operations are based on a plurality of read voltages, determining, using the one or more parameters as an input to a deep neural network comprising a plurality of layers, an updated plurality of read voltages, wherein each of the plurality of layers is a fully connected layer, and applying the updated plurality of read voltages to the memory device to retrieve information from the memory device, wherein the deep neural network uses a plurality of weights that have been processed using at least one of (a) a pruning operation, (b) a non-uniform quantization operation, or (c) a Huffman encoding operation.
    Type: Application
    Filed: September 1, 2021
    Publication date: March 9, 2023
    Inventors: Seyhan KARAKULAK, Haobo WANG, Aman BHATIA, Fan ZHANG
  • Patent number: 11574698
    Abstract: Devices, systems and methods for improving performance of a memory device are described. An example method includes receiving one or more parameters associated with a plurality of previous read operations on a page of the memory device, wherein the previous read operations are based on a plurality of read voltages, determining, using the one or more parameters as an input to a deep neural network comprising a plurality of layers, an updated plurality of read voltages, wherein each of the plurality of layers is a fully connected layer, and applying the updated plurality of read voltages to the memory device to retrieve information from the memory device, wherein the deep neural network uses a plurality of weights that have been processed using at least one of (a) a pruning operation, (b) a non-uniform quantization operation, or (c) a Huffman encoding operation.
    Type: Grant
    Filed: September 1, 2021
    Date of Patent: February 7, 2023
    Assignee: SK hynix Inc.
    Inventors: Seyhan Karakulak, Haobo Wang, Aman Bhatia, Fan Zhang
  • Patent number: 11574697
    Abstract: Devices, systems and methods for improving a decoding operation in a non-volatile memory are described. An example method includes performing a first hard read to obtain a first set of values stored in a plurality of cells, storing the first set of values in a first buffer, performing a plurality of subsequent hard reads on the plurality of cells to obtain a plurality of subsequent sets of values, performing, for each subsequent set of values, the following operations: computing a quality metric, storing, in a second buffer, a difference between the subsequent set of values and the set of values stored in the first buffer, wherein the difference is stored in a compressed format, and storing, in response to the quality metric exceeding a threshold, the subsequent set of values in the first buffer, and generating, based on the first buffer and the second buffer, the log-likelihood ratio.
    Type: Grant
    Filed: June 10, 2021
    Date of Patent: February 7, 2023
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Haobo Wang
  • Publication number: 20230036490
    Abstract: Embodiments provide a scheme for estimating an optimal read threshold voltage using a deep neural network (DNN) with reduced number of processing. A controller receives first and second program voltage (PV) levels associated with read operations on cells. The controller estimates first and second probability distribution parameter sets representing skew normal distributions of the first and second PV levels, respectively. The controller estimates an optimal read threshold voltage based on the first and second probability distribution parameter sets. The optimal read threshold voltage is a read threshold voltage such that first probability density function (PDF) value of the skew normal distribution of the first PV level is the same as the second PDF value of the skew normal distribution of the second PV level.
    Type: Application
    Filed: July 27, 2021
    Publication date: February 2, 2023
    Inventors: Haobo WANG, Aman BHATIA, Fan ZHANG
  • Publication number: 20230035983
    Abstract: Embodiments provide a scheme for estimating an optimal read threshold voltage using a deep neural network (DNN) with a reduced number of processing. A controller includes a combined neural network, which receives first and second cumulative distribution function (CDF) values, each CDF value corresponding to a program voltage (PV) level associated with a read operation on the cells. The combined neural network generates first and second connection vectors based on the first and second CDF values and first weight values, and estimates an optimal read threshold voltage based on the first and second connection vectors and second weight values.
    Type: Application
    Filed: July 27, 2021
    Publication date: February 2, 2023
    Inventors: Haobo WANG, Aman BHATIA, Fan ZHANG
  • Publication number: 20220399071
    Abstract: Devices, systems and methods for improving a decoding operation in a non-volatile memory are described. An example method includes performing a first hard read to obtain a first set of values stored in a plurality of cells, storing the first set of values in a first buffer, performing a plurality of subsequent hard reads on the plurality of cells to obtain a plurality of subsequent sets of values, performing, for each subsequent set of values, the following operations: computing a quality metric, storing, in a second buffer, a difference between the subsequent set of values and the set of values stored in the first buffer, wherein the difference is stored in a compressed format, and storing, in response to the quality metric exceeding a threshold, the subsequent set of values in the first buffer, and generating, based on the first buffer and the second buffer, the log-likelihood ratio.
    Type: Application
    Filed: June 10, 2021
    Publication date: December 15, 2022
    Inventors: Fan ZHANG, Aman BHATIA, Haobo WANG
  • Patent number: 11502703
    Abstract: A descrambler receives data from a memory device. The descrambler calculates a sub-syndrome weight for multiple bits in each of the plurality of descrambled sequences using a set parity check matrix to generate multiple sub-syndrome weights, one for each of the plurality of descrambled sequences. The descrambler selects a sub-syndrome weight among the multiple sub-syndrome weights. The descrambler determines, as a correct scrambler sequence for descrambling the data, a scrambler sequence corresponding to the selected sub-syndrome weight, among the plurality of scrambler sequences.
    Type: Grant
    Filed: May 20, 2020
    Date of Patent: November 15, 2022
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Xuanxuan Lu, Haobo Wang, Meysam Asadi
  • Patent number: 11456757
    Abstract: Devices, systems, and methods for detecting and mitigating oscillations in a bit-flipping decoder associated with a non-volatile memory are described. An example method includes receiving a noisy codeword based on a transmitted codeword generated from a low-density parity-check code, performing a first plurality of decoding iterations on the noisy codeword, which comprises performing a message passing algorithm in a first order, computing, based on a completion of the first plurality of decoding iterations, a plurality of checksum values and a plurality of bit flip counts corresponding to the first plurality of decoding iterations, determining that the plurality of checksum values and the plurality of bit flip counts are periodic with a period less than a predetermined threshold, and performing a subsequent decoding iteration on the noisy codeword, the subsequent decoding iteration comprising performing the message passing algorithm in a second order different from the first order.
    Type: Grant
    Filed: December 16, 2020
    Date of Patent: September 27, 2022
    Assignee: SK hynix Inc.
    Inventors: Meysam Asadi, Aman Bhatia, Fan Zhang, Haobo Wang
  • Patent number: 11430530
    Abstract: Devices, systems and methods for improving the performance of a memory device are described. An example method includes obtaining a plurality of cell counts for each of a plurality of read voltages applied to the memory device, generating, based on the plurality of cell counts and the plurality of read voltages, at least one ones count, at least one checksum, and a plurality of samples corresponding to a distribution function of at least one read voltage of the plurality of read voltages, determining an updated value for the at least one read voltage based on an output of a deep neural network whose input comprises the at least one ones count, the at least one checksum, and the plurality of samples, and applying the updated value of the at least one read voltage to the memory device to retrieve information from the memory device.
    Type: Grant
    Filed: January 25, 2021
    Date of Patent: August 30, 2022
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Haobo Wang
  • Publication number: 20220238168
    Abstract: Devices, systems and methods for improving the performance of a memory device are described. An example method includes obtaining a plurality of cell counts for each of a plurality of read voltages applied to the memory device, generating, based on the plurality of cell counts and the plurality of read voltages, at least one ones count, at least one checksum, and a plurality of samples corresponding to a distribution function of at least one read voltage of the plurality of read voltages, determining an updated value for the at least one read voltage based on an output of a deep neural network whose input comprises the at least one ones count, the at least one checksum, and the plurality of samples, and applying the updated value of the at least one read voltage to the memory device to retrieve information from the memory device.
    Type: Application
    Filed: January 25, 2021
    Publication date: July 28, 2022
    Inventors: Fan ZHANG, Aman BHATIA, Haobo WANG
  • Patent number: 11380410
    Abstract: Devices, systems and methods for improving the performance of a memory device are described. An example method includes obtaining a plurality of cell counts for each of a plurality of read voltages applied to the memory device, generating, based on the plurality of cell counts and the plurality of read voltages, at least one ones count, at least one checksum, and a plurality of samples corresponding to a distribution function of at least one read voltage of the plurality of read voltages, determining an updated value for the at least one read voltage based on an output of a deep neural network whose input comprises the at least one ones count, the at least one checksum, and the plurality of samples, and applying the updated value of the at least one read voltage to the memory device to retrieve information from the memory device.
    Type: Grant
    Filed: January 25, 2021
    Date of Patent: July 5, 2022
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Haobo Wang
  • Publication number: 20220190845
    Abstract: Devices, systems, and methods for detecting and mitigating oscillations in a bit-flipping decoder associated with a non-volatile memory are described. An example method includes receiving a noisy codeword based on a transmitted codeword generated from a low-density parity-check code, performing a first plurality of decoding iterations on the noisy codeword, which comprises performing a message passing algorithm in a first order, computing, based on a completion of the first plurality of decoding iterations, a plurality of checksum values and a plurality of bit flip counts corresponding to the first plurality of decoding iterations, determining that the plurality of checksum values and the plurality of bit flip counts are periodic with a period less than a predetermined threshold, and performing a subsequent decoding iteration on the noisy codeword, the subsequent decoding iteration comprising performing the message passing algorithm in a second order different from the first order.
    Type: Application
    Filed: December 16, 2020
    Publication date: June 16, 2022
    Inventors: Meysam Asadi, Aman Bhatia, Fan Zhang, Haobo Wang
  • Patent number: 11355204
    Abstract: Techniques related to methods and systems for improving a performance related to reading data stored in memory cells. The method includes selecting a first voltage read range and a second voltage read range from multiple voltage read ranges that are associated with a number of bits storable in a memory cell. The method includes receiving, a first set of parameters that represent a first probability distribution of first candidate voltage read thresholds within the first voltage read range. The method includes receiving a second set of parameters that represent a second probability distribution of second candidate voltage read thresholds within the second voltage read range. The method includes generating, based on an input to an objective function, a voltage read threshold. The method includes reading data stored in the memory cell based on the voltage read threshold.
    Type: Grant
    Filed: September 3, 2020
    Date of Patent: June 7, 2022
    Assignee: SK hynix Inc.
    Inventors: Aman Bhatia, Haobo Wang, Fan Zhang
  • Patent number: 11356123
    Abstract: Memory controllers, decoders and methods to selectively perform bit-flipping (BF) decoding and min-sum (MS) decoding on codewords of an irregular low-density parity-check (LDPC) code. Bit-flipping (BF) decoding is executed with respect to variable nodes having relatively high column weights. MS decoding is executed with respect to variable nodes having relatively low column weights. A column-weight threshold is used to group the variable nodes into the higher and lower column weight groups. The two decoding techniques exchange results during the overall decoding process.
    Type: Grant
    Filed: July 12, 2019
    Date of Patent: June 7, 2022
    Assignee: SK hynix Inc.
    Inventors: Chenrong Xiong, Fan Zhang, Haobo Wang, Xuanxuan Lu, Meysam Asadi
  • Patent number: 11335417
    Abstract: A controller optimizes a read threshold value for a memory device using model-less regression. The controller performs read operations on cells using read threshold voltage values. The controller measures probability values for the multiple read threshold voltage values, and estimates a threshold voltage distribution curve based on the multiple read threshold voltage values and the measured probability values using a set regression formula. The controller determines a read threshold voltage value corresponding to a set point on the threshold voltage distribution curve, and performs a read operation on the cells using the read threshold voltage value.
    Type: Grant
    Filed: October 28, 2020
    Date of Patent: May 17, 2022
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Xuanxuan Lu, Meysam Asadi, Haobo Wang
  • Patent number: 11322214
    Abstract: Devices, systems and methods for improving the performance of a memory device are described. An example method includes obtaining a plurality of cell counts for each of a plurality of read voltages applied to the memory device, generating, based on the plurality of cell counts, a set of Gaussian models for a plurality of PV states corresponding to the plurality of read voltages, each of the set of Gaussian models comprising a mean parameter and a standard deviation parameter, determining, based on the set of Gaussian models, the mean parameter and the standard deviation parameter for each of the plurality of PV states, determining, based on the mean parameter and the standard deviation parameter for each of the plurality of PV states, a plurality of updated read voltages, and applying the plurality of updated read voltages to the memory device to retrieve information from the memory device.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: May 3, 2022
    Assignee: SK hynix Inc.
    Inventors: Fan Zhang, Aman Bhatia, Haobo Wang, Meysam Asadi
  • Publication number: 20220130472
    Abstract: A controller optimizes a read threshold value for a memory device using model-less regression. The controller performs read operations on cells using read threshold voltage values. The controller measures probability values for the multiple read threshold voltage values, and estimates a threshold voltage distribution curve based on the multiple read threshold voltage values and the measured probability values using a set regression formula. The controller determines a read threshold voltage value corresponding to a set point on the threshold voltage distribution curve, and performs a read operation on the cells using the read threshold voltage value.
    Type: Application
    Filed: October 28, 2020
    Publication date: April 28, 2022
    Inventors: Fan ZHANG, Aman BHATIA, Xuanxuan LU, Meysam ASADI, Haobo WANG
  • Patent number: D985103
    Type: Grant
    Filed: November 25, 2022
    Date of Patent: May 2, 2023
    Assignee: GUANGZHOU MIBO ZHILIAN TECHNOLOGY CO. LTD
    Inventors: Ziyi Long, Haobo Wang