Patents by Inventor Zhengang Chen

Zhengang Chen 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).

  • Publication number: 20210012857
    Abstract: A processing device in a memory system identifies a first range of a plurality of write-to-read delay ranges for the memory component, wherein the first range represents a plurality of write-to-read delay times and has an associated read voltage level used to perform a read operation on a segment of the memory component having a write-to-read delay time that falls within the first range. The processing device further identifies a first set of the plurality of write-to-read delay times at a first end of the first range and a second set of the plurality of write-to-read delay times at a second end of the first range, and determines a first error rate for the memory component corresponding to the first set of the plurality of write-to-read delay times and a second error rate for the memory component corresponding to the second set of the plurality of write-to-read delay times.
    Type: Application
    Filed: July 12, 2019
    Publication date: January 14, 2021
    Inventors: Tingjun Xie, Zhengang Chen
  • Publication number: 20210011769
    Abstract: An indication that an allocation unit of a memory sub-system has become unmapped can be received. In response to receiving the indication that the allocation unit of the memory sub-system has become unmapped, the allocation unit can be programmed with a data pattern. Data to be written to the unmapped allocation unit can be received. A write operation can be performed to program the received data at the unmapped allocation unit by using a read voltage that is based on the data pattern.
    Type: Application
    Filed: July 12, 2019
    Publication date: January 14, 2021
    Inventors: Tingjun Xie, Zhengang Chen, Zhenlei Shen
  • Publication number: 20210012856
    Abstract: A processing device in a memory system identifies a first range of a plurality of write-to-read delay ranges for the memory component, wherein the first range represents a plurality of write-to-read delay times and has an associated read voltage level used to perform a read operation on a segment of the memory component having a write-to-read delay time that falls within the first range. The processing device further identifies a first set of the plurality of write-to-read delay times at a first end of the first range and determines a first directional error rate for the memory component corresponding to the first set of the plurality of write-to-read delay times and a second directional error rate for the memory component corresponding to the first set of the plurality of write-to-read delay times.
    Type: Application
    Filed: July 12, 2019
    Publication date: January 14, 2021
    Inventors: Tingjun Xie, Zhengang Chen
  • Patent number: 10892029
    Abstract: A processing device in a memory system identifies a first range of a plurality of write-to-read delay ranges for the memory component, wherein the first range represents a plurality of write-to-read delay times and has an associated read voltage level used to perform a read operation on a segment of the memory component having a write-to-read delay time that falls within the first range. The processing device further identifies a first set of the plurality of write-to-read delay times at a first end of the first range and determines a first directional error rate for the memory component corresponding to the first set of the plurality of write-to-read delay times and a second directional error rate for the memory component corresponding to the first set of the plurality of write-to-read delay times.
    Type: Grant
    Filed: July 12, 2019
    Date of Patent: January 12, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Tingjun Xie, Zhengang Chen
  • Patent number: 10877835
    Abstract: A read operation to retrieve data from memory component and that bypasses a prior search for the data at a buffer in a read data path associated with the read operation can be performed. Responsive to performing the read operation that bypasses the prior search for the data at the buffer, the data is returned to a host system.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: December 29, 2020
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Wei Wang, Jiangli Zhu, Ying Yu Tai, Ning Chen, Zhengang Chen, Cheng Yuan Wu
  • Publication number: 20200363969
    Abstract: First data can be received at a memory sub-system. An operating temperature of the memory sub-system can be identified. An adjusted read voltage level can be determined in response to the operating temperature satisfying a threshold criterion pertaining to a threshold temperature. A read operation can be performed at the memory sub-system based on the adjusted read voltage level to retrieve second data. The first data can be stored at the memory sub-system based on the second data that was retrieved from the read operation that is based on the adjusted read voltage level.
    Type: Application
    Filed: July 20, 2020
    Publication date: November 19, 2020
    Inventors: Zhenlei E. Shen, Zhengang Chen, Tingjun Xie, Jiangli Zhu
  • Publication number: 20200356441
    Abstract: Data stored on each of a set of memory components can be read. Corresponding data stored on a number of the set of memory components that cannot be decoded using an error correction code decoding operation can be identified. A determination can be made whether the number of the set of memory components that include the corresponding data that cannot be decoded from the ECC decoding operation satisfies a threshold condition. Responsive to determining that the number of the set of memory components that include the corresponding data that cannot be decoded from the second ECC decoding operation satisfies the threshold condition, a processing device, can perform a redundancy error correction decoding operation to correct the data stored on each of the set of memory components.
    Type: Application
    Filed: July 28, 2020
    Publication date: November 12, 2020
    Inventors: Ying Yu Tai, Jiangli Zhu, Zhengang Chen
  • Patent number: 10783978
    Abstract: A system includes memory dice, each having a register to store multiple read voltage levels. A processing device is to test each memory die by verification, via access to the multiple read voltage levels, whether each read voltage level falls within a corresponding relative voltage range. The processing device selects an initial read voltage level that achieves bit error rates not satisfying a threshold criterion at one of a first or a second shortest write-to-read (W2R) delay for the memory die and determines a bit error rate, using the initial read voltage level, of storage units of the memory die. The processing device reports the memory die as defective in response to one of: (i) a read voltage level, of the multiple read voltage levels, failing to verify; or (ii) the bit error rate of one or more storage units of the memory die satisfying the threshold criterion.
    Type: Grant
    Filed: August 27, 2019
    Date of Patent: September 22, 2020
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Zhengang Chen, Tingjun Xie, Steven M. Pope
  • Patent number: 10761754
    Abstract: Data can be received at a memory sub-system. A characteristic of the memory sub-system can be identified. A read voltage level can be determined based on the characteristic of the memory sub-system. A read operation can be performed at the memory sub-system based on the read voltage level to retrieve stored data. The received data can be stored at the memory sub-system based on the stored data that was retrieved from the read operation that is based on the read voltage level.
    Type: Grant
    Filed: August 7, 2018
    Date of Patent: September 1, 2020
    Assignee: Micron Technology, Inc.
    Inventors: Zhenlei E. Shen, Zhengang Chen, Tingjun Xie, Jiangli Zhu
  • Patent number: 10747614
    Abstract: Data stored on each of a set of memory components can be read. Corresponding data stored on a number of the set of memory components that cannot be decoded using an error correction code decoding operation can be identified. A determination can be made whether the number of the set of memory components that include the corresponding data that cannot be decoded from the ECC decoding operation satisfies a threshold condition. Responsive to determining that the number of the set of memory components that include the corresponding data that cannot be decoded from the second ECC decoding operation satisfies the threshold condition, a processing device, can perform a redundancy error correction decoding operation to correct the data stored on each of the set of memory components.
    Type: Grant
    Filed: July 23, 2018
    Date of Patent: August 18, 2020
    Assignee: Micron Technology, Inc.
    Inventors: Ying Yu Tai, Jiangli Zhu, Zhengang Chen
  • Publication number: 20200183783
    Abstract: Described herein are embodiments related to one-direction error recovery flow (ERF) operations on memory components of memory systems. A processing device determines that data from a read operation is not successfully decoded because of a partial write of the data. The partial write results from a number of memory cells written as a first state and read as a second state. The processing device performs a one-direction ERF on the memory cells by monotonically adjusting a read voltage level for one or more re-read operations from a first discrete read voltage level towards a second read voltage level in a first direction until the data from the one or more re-read operations is successfully decoded. The first direction corresponds to an opposite direction of a state shift of the partial write. The processing device can also can determine a directional EBC and perform a refresh write if necessary.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 11, 2020
    Inventors: Tingjun Xie, Zhengang Chen
  • Publication number: 20200185045
    Abstract: Described herein are embodiments related to defect detection in memory components of memory systems with time-varying bit error rate. A processing device performs an error recovery flow (ERF) to recover a unit of data comprising data and a write timestamp indicating when the unit of data was written. The processing device determines whether to perform a defect detection operation to detect a defect in the memory component using a bit error rate (BER), corresponding to the read operation, and the write timestamp in the unit of data. The processing device initiates the defect detection operation responsive to the BER condition not being expected for the calculated W2R (based on the write timestamp). The processing device can use an ERF condition and the write timestamp to determine whether to perform the defect detection operation. The processing device initiates the defect detection operation responsive to the ERF condition not being expected the calculated W2R (based on the write timestamp).
    Type: Application
    Filed: December 10, 2018
    Publication date: June 11, 2020
    Inventors: Zhengang Chen, Sai Krishna Mylavarapu, Zhenlei Shen, Tingjun Xie, Charles S. Kwong
  • Publication number: 20200177205
    Abstract: Codewords of an error correcting code can be received. The codewords can be separated into multiple segments. The segments of the codewords can be distributed in an error correcting layout across a plurality of dies where at least a portion of the error correcting layout constitutes a Latin Square (LS) layout.
    Type: Application
    Filed: November 29, 2018
    Publication date: June 4, 2020
    Inventors: Wei Wu, Zhenlei Shen, Zhengang Chen
  • Patent number: 10580514
    Abstract: Log likelihood ratio (LLR) values that are computed in a flash memory controller during read retries change over time as the number of program-and-erase cycles (PECs) that the flash memory die has been subjected to increases. Therefore, in cases where an LLR table is used to provide pre-defined, fixed LLR values to the error-correcting code (ECC) decoding logic of the controller, decoding success and the resulting BER will degrade over time as the number of PECs to which the die has been subjected increases. In accordance with embodiments, a storage system, a flash memory controller for use in the storage system and method are provided that periodically measure the LLR values and update the LLR table with new LLR values. Periodically measuring the LLR values and updating the LLR table with new LLR values ensures high decoding success and a low BER over the life of the flash memory die.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: March 3, 2020
    Assignee: Seagate Technology LLC
    Inventors: Yunxiang Wu, Yu Cai, Zhengang Chen, Erich Haratsch
  • Publication number: 20200050383
    Abstract: Data can be received at a memory sub-system. A characteristic of the memory sub-system can be identified. A read voltage level can be determined based on the characteristic of the memory sub-system. A read operation can be performed at the memory sub-system based on the read voltage level to retrieve stored data. The received data can be stored at the memory sub-system based on the stored data that was retrieved from the read operation that is based on the read voltage level.
    Type: Application
    Filed: August 7, 2018
    Publication date: February 13, 2020
    Inventors: Zhenlei E. Shen, Zhengang Chen, Tingjun Xie, Jiangli Zhu
  • Publication number: 20200026595
    Abstract: A read operation to retrieve data from memory component and that bypasses a prior search for the data at a buffer in a read data path associated with the read operation can be performed. Responsive to performing the read operation that bypasses the prior search for the data at the buffer, the data is returned to a host system.
    Type: Application
    Filed: July 19, 2018
    Publication date: January 23, 2020
    Inventors: Wei Wang, Jiangli Zhu, Ying Yu Tai, Ning Chen, Zhengang Chen, Cheng Yuan Wu
  • Publication number: 20200026602
    Abstract: Data stored on each of a set of memory components can be read. Corresponding data stored on a number of the set of memory components that cannot be decoded using an error correction code decoding operation can be identified. A determination can be made whether the number of the set of memory components that include the corresponding data that cannot be decoded from the ECC decoding operation satisfies a threshold condition. Responsive to determining that the number of the set of memory components that include the corresponding data that cannot be decoded from the second ECC decoding operation satisfies the threshold condition, a processing device, can perform a redundancy error correction decoding operation to correct the data stored on each of the set of memory components.
    Type: Application
    Filed: July 23, 2018
    Publication date: January 23, 2020
    Inventors: Ying Yu Tai, Jiangli Zhu, Zhengang Chen
  • Publication number: 20190385694
    Abstract: An apparatus includes a memory and a controller. The memory may be configured to store data. The controller may be configured to process a plurality of input/output requests to a plurality of blocks of the memory that are not marked as bad on a block list, perform a code rate test that programs the plurality of blocks of the memory at three or more code rates of an error correction code scheme, and mark any of the plurality of blocks identified as bad during the code rate test on the block list.
    Type: Application
    Filed: August 27, 2019
    Publication date: December 19, 2019
    Inventors: Zhengang Chen, David Patmore, Yingji Ju, Erich F. Haratsch
  • Publication number: 20190348133
    Abstract: Channel information and channel conditions determined by an Offline Tracking process are used to determine whether or not an adjustment to the read reference voltage can be avoided altogether without detrimentally affecting performance, or, alternatively, to determine a precision with which a read reference voltage adjustment should be made. If it is determined based on the channel conditions that a read reference voltage adjustment can be avoided altogether, read performance is improved by reducing the probability that a read reference voltage adjustment needs to be made during normal read operations. If it is determined based on the channel conditions that a read reference voltage adjustment needs to be made with a particular precision, the read reference voltage is so adjusted. This latter approach is advantageous in that relatively fewer adjustments will be made during normal read operations.
    Type: Application
    Filed: July 22, 2019
    Publication date: November 14, 2019
    Inventors: Zhengang Chen, Erich F. Haratsch, Sundararajan Sankaranarayanan
  • Patent number: 10468096
    Abstract: A memory device includes a memory array comprising multi-level memory cells, and control circuitry coupled to the memory array. The control circuitry is configured to perform accelerated soft read operations on at least a portion of the memory array. A given one of the accelerated soft read operations directed to a non-upper page of the memory array comprises at least one hard read operation directed to a corresponding upper page of the memory array. The given accelerated soft read operation may comprise a sequence of multiple hard read operations including a hard read operation directed to the non-upper page and one or more hard read operations directed to the corresponding upper page.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: November 5, 2019
    Assignee: Seagate Technology LLC
    Inventors: Zhengang Chen, Hao Zhong