Patents by Inventor Won-Ho Choi

Won-Ho Choi 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: 11099784
    Abstract: Apparatuses and techniques are described for reading crosspoint arrays of memory cells with high bandwidth and a relatively small page buffer. Multiple crosspoint arrays (XPAs) are read in parallel, with one memory cell per XPA being read, in a bank of XPAs. To reduce the read time, a row can be selected for the XPAs, after which memory cells in different columns are read, one column at a time, while the same row is selected. This avoids the need to transmit commands and a row address for re-selecting the row in each successive read operation. The XPAs may be ungrouped, or one XPA may be accessible at a time in a group. In one option, the XPAs are arranged in sets, either individually or in groups, and one set is accessible at a time.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: August 24, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Won Ho Choi, Ward Parkinson, Raj Ramanujan, Martin Lueker-Boden
  • Patent number: 11081148
    Abstract: An illustrative embodiment disclosed herein is an apparatus including a non-volatile memory cell and multi-bit input circuitry that simultaneously receives a plurality of bits, receives a supply voltage, converts the plurality of bits and the supply voltage into a multiply voltage, and applies the multiply voltage to the non-volatile memory cell. The non-volatile memory cell may pass a memory cell current in response to the multiply voltage. A magnitude of the multiply voltage may represent a multiplier. The memory cell current may represent a product of the multiplier and a multiplicand stored in the non-volatile memory cell.
    Type: Grant
    Filed: June 12, 2020
    Date of Patent: August 3, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Won Ho Choi, Pi-Feng Chiu, Martin Lueker-Boden
  • Publication number: 20210233592
    Abstract: Systems and methods for performing in-storage logic operations using one or more memory cell transistors and a programmable sense amplifier are described. The logic operations may comprise basic Boolean logic operations (e.g., OR and AND operations) or secondary Boolean logic operations (e.g., XOR and IMP operations). The one or more memory cell transistors may be used for storing user data during a first time period and then used for performing a logic operation during a second time period subsequent to the first time period. During the logic operation, a first memory cell transistor of the one or more memory cell transistors may be programmed with a threshold voltage that corresponds with a first input operand value and then a gate voltage bias may be applied to the first memory cell transistor during the logic operation that corresponds with a second input operand value.
    Type: Application
    Filed: January 29, 2020
    Publication date: July 29, 2021
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Federico Nardi, Won Ho Choi
  • Patent number: 11074318
    Abstract: An innovative low-bit-width device may include a first digital-to-analog converter (DAC), a second DAC, a plurality of non-volatile memory (NVM) weight arrays, one or more analog-to-digital converters (ADCs), and a neural circuit. The first DAC is configured to convert a digital input signal into an analog input signal. The second DAC is configured to convert a digital previous hidden state (PHS) signal into an analog PHS signal. NVM weight arrays are configured to compute vector matrix multiplication (VMM) arrays based on the analog input signal and the analog PHS signal. The NVM weight arrays are coupled to the first DAC and the second DAC. The one or more ADCs are coupled to the plurality of NVM weight arrays and are configured to convert the VMM arrays into digital VMM values. The neural circuit is configured to process the digital VMM values into a new hidden state.
    Type: Grant
    Filed: June 25, 2019
    Date of Patent: July 27, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: Wen Ma, Pi-Feng Chiu, Minghai Qin, Won Ho Choi, Martin Lueker-Boden
  • Publication number: 20210222834
    Abstract: Disclosed is system for automatically replacing a high-pressure gas tank, including: a high-pressure gas tank lift installed in a cabinet which is able to be elevated and including a die to load a high-pressure gas tank thereon; a high-pressure gas tank clamp clamping the high-pressure gas tank loaded on the die of the high-pressure gas tank lift to align the position of the high-pressure gas tank; a high-pressure gas tank connection unit removing an end cap from the high-pressure gas tank elevated by the high-pressure gas tank lift to automatically connect a connector holder to a gas injection nozzle and control the flow of gas; and control unit installed in the cabinet to control operation of the high-pressure gas tank connection unit, the high-pressure gas tank lift, and the high-pressure gas tank clamp.
    Type: Application
    Filed: November 14, 2018
    Publication date: July 22, 2021
    Applicant: AMT CO., LTD.
    Inventors: Won Ho CHOI, Chan Woo KIM
  • Publication number: 20210199692
    Abstract: There is provided a probe pin for performing an electrical inspection between a contact pad of a test apparatus and a conductive ball of a semiconductor device, the probe pin including a cylinder-type bottom plunger connected to the contact pad and configured to slide vertically, a piston-type top plunger connected to the conductive ball and configured to slide vertically, and an outer spring configured to provide an elastic force between the bottom plunger and the top plunger. According to the configuration of the present invention, it is possible to perform a stable inspection process by using the outer spring despite pin miniaturization.
    Type: Application
    Filed: March 6, 2020
    Publication date: July 1, 2021
    Inventors: Jin Kook JUN, Eun Hyeong PYO, Won Ho CHOI
  • Publication number: 20210192325
    Abstract: Techniques are presented for performing in-memory matrix multiplication operations for binary input, binary weight valued convolution neural network (CNN) inferencing. The weights of a filter are stored in pairs of memory cells of a storage class memory device, such as a ReRAM or phase change memory based devices. To reduce current consumption, the binary valued filters are transformed into ternary valued filters by taking sums and differences of binary valued filter pairs. The zero valued weights of the transformed filters are stored as a pair of high resistance state memory cells, reducing current consumption during convolution. The results of the in-memory multiplications are pair-wise combined to compensate for the filter transformations. To compensate for zero valued weights, a zero weight register stores the number of zero weights along each bit line and is used to initialize counter values for accumulating the multiplication operations.
    Type: Application
    Filed: December 20, 2019
    Publication date: June 24, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Tung Thanh Hoang, Won Ho Choi, Martin Lueker-Boden
  • Publication number: 20210190269
    Abstract: Disclosed is a method for automatically replacing high-pressure gas barrels, in which when loading a high-pressure gas barrel is loaded on the lift of a cabinet so as to supply gas to the wafer production line in the semiconductor fabrication FAB process facility, at the time point of replacement of the high-pressure gas barrel, a used high-pressure gas barrel is separated from a connector holder and then a new high-pressure gas barrel is connected to the connector holder.
    Type: Application
    Filed: December 19, 2018
    Publication date: June 24, 2021
    Applicant: AMT CO., LTD.
    Inventor: Won Ho CHOI
  • Publication number: 20210190268
    Abstract: Disclosed is an automatic alignment method of a high-pressure gas container in which a high-pressure gas container is loaded on a lift of a cabinet so as to supply a gas from a fabrication (FAB) process facility of a semiconductor to a wafer production line, and then, the high-pressure gas container loaded on the lift is raised, and an end cap of the high-pressure gas container and the center of a connector holder of a gas pipe are automatically aligned.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 24, 2021
    Applicant: AMT CO., LTD.
    Inventors: Won Ho CHOI, Chan Woo KIM
  • Publication number: 20210181979
    Abstract: Apparatuses and techniques are described for reading crosspoint arrays of memory cells with high bandwidth and a relatively small page buffer. Multiple crosspoint arrays (XPAs) are read in parallel, with one memory cell per XPA being read, in a bank of XPAs. To reduce the read time, a row can be selected for the XPAs, after which memory cells in different columns are read, one column at a time, while the same row is selected. This avoids the need to transmit commands and a row address for re-selecting the row in each successive read operation. The XPAs may be ungrouped, or one XPA may be accessible at a time in a group. In one option, the XPAs are arranged in sets, either individually or in groups, and one set is accessible at a time.
    Type: Application
    Filed: December 17, 2019
    Publication date: June 17, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Won Ho Choi, Ward Parkinson, Raj Ramanujan, Martin Lueker-Boden
  • Publication number: 20210173560
    Abstract: Methods and apparatus are disclosed for implementing principal component analysis (PCA) within a non-volatile memory (NVM) die of solid state drive (SSD) to reduce the dimensionality of machine learning data before the data is transferred to other components of the SSD, such as to a data storage controller equipped with a machine learning engine. The machine learning data may include, for example, training images for training an image recognition system in which the SSD is installed. In some examples, the on-chip PCA components of the NVM die are configured as under-the-array or next-to-the-array components. In other examples, one or more arrays of the NVM die are configured as multiplication cores for performing PCA matrix multiplication. In still other aspects, multiple NVM dies are arranged in parallel, each with on-chip PCA components to permit parallel concurrent on-chip processing of machine learning data.
    Type: Application
    Filed: December 6, 2019
    Publication date: June 10, 2021
    Inventors: Won Ho Choi, Yongjune Kim, Martin Lueker-Boden
  • Patent number: 11031061
    Abstract: A system and method include determining, by a memory controller associated with a memory device, a value of a parameter of a write pulse for a plurality of bits of a B-bit word to be stored in the memory device. The value of the parameter is based upon a relative importance of a bit position of the plurality of bits in the B-bit word to a performance of a machine learning or signal processing task involving the B-bit word, a fidelity metric, and a resource metric. The system and method also include writing each of the plurality of bits of the B-bit word in a different sub-array of the memory device using the write pulse generated based on the value of the parameter determined for a particular one of the plurality of bits.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: June 8, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yongjune Kim, Yoocharn Jeon, Won Ho Choi, Cyril Guyot, Yuval Cassuto
  • Publication number: 20210156520
    Abstract: Disclosed is a device for automatically opening or closing a gas barrel valve. The device includes: a main plate installed so as to move up and down and to align the position of a gas barrel loaded in a cabinet; a gas barrel connecting portion installed on the lower portion of the main plate, separating an end cap from the gas barrel and storing the end cap, and then automatically screw-coupling a connector holder to a gas spray nozzle; a valve handle unit installed on the main plate so as to rotate around a first shaft and rotating a valve handle of the gas barrel such that the valve handle is locked or unlocked, while encompassing the valve handle of the gas barrel; and a valve handle opening or closing unit installed on the upper portion of the main plate so as to operate the valve handle unit in a direction, in which a valve of the gas barrel is opened.
    Type: Application
    Filed: August 2, 2018
    Publication date: May 27, 2021
    Applicant: AMT CO., LTD.
    Inventors: Du Chul KIM, Jong Seong LEE, Won Ho CHOI
  • Patent number: 10991414
    Abstract: A system and method for refreshing memory cells of a memory device includes storing each bit of a B-bit word in a different sub-array of a memory device. Each of the bits is associated with a bit position, and the memory device includes a plurality of sub-arrays. The system and method also include determining a refresh interval for a plurality of the bit positions based upon a relative importance of the plurality of the bit positions to a performance of a machine learning or signal processing task involving the B-bit word. The refresh interval is based upon a fidelity metric and a resource metric. The system and method further include refreshing the plurality of sub-arrays based upon the refresh interval determined for the plurality of bit positions, and dynamically updating the refresh interval for the plurality of bit positions upon receiving a new fidelity metric or a new resource metric.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: April 27, 2021
    Assignee: Western Digital Technologies, Inc.
    Inventors: Yongjune Kim, Won Ho Choi, Cyril Guyot, Yuval Cassuto
  • Publication number: 20210117499
    Abstract: Systems and methods for reducing the impact of defects within a crossbar memory array when performing multiplication operations in which multiple control lines are concurrently selected are described. A group of memory cells within the crossbar memory array may be controlled by a local word line that is controlled by a local word line gating unit that may be configured to prevent the local word line from being biased to a selected word line voltage during an operation; the local word line may instead be set to a disabling voltage during the operation such that the memory cell currents through the group of memory cells are eliminated. If a defect has caused a short within one of the memory cells of the group of memory cells, then the local word line gating unit may be programmed to hold the local word line at the disabling voltage during multiplication operations.
    Type: Application
    Filed: October 17, 2019
    Publication date: April 22, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Minghai Qin, Pi-Feng Chiu, Wen Ma, Won Ho Choi
  • Publication number: 20210117500
    Abstract: Systems and methods for reducing the impact of defects within a crossbar memory array when performing multiplication operations in which multiple control lines are concurrently selected are described. A group of memory cells within the crossbar memory array may be controlled by a local word line that is controlled by a local word line gating unit that may be configured to prevent the local word line from being biased to a selected word line voltage during an operation; the local word line may instead be set to a disabling voltage during the operation such that the memory cell currents through the group of memory cells are eliminated. If a defect has caused a short within one of the memory cells of the group of memory cells, then the local word line gating unit may be programmed to hold the local word line at the disabling voltage during multiplication operations.
    Type: Application
    Filed: June 26, 2020
    Publication date: April 22, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Minghai Qin, Pi-Feng Chiu, Wen Ma, Won Ho Choi
  • Publication number: 20210110235
    Abstract: Techniques are presented for accelerating in-memory matrix multiplication operations for a convolution neural network (CNN) inference in which the weights of a filter are stored in the memory of a storage class memory device, such as a ReRAM or phase change memory based device. To improve performance for inference operations when filters exhibit sparsity, a zero column index and a zero row index are introduced to account for columns and rows having all zero weight values. These indices can be saved in a register on the memory device and when performing a column/row oriented matrix multiplication, if the zero row/column index indicates that the column/row contains all zero weights, the access of the corresponding bit/word line is skipped as the result will be zero regardless of the input.
    Type: Application
    Filed: October 15, 2019
    Publication date: April 15, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Tung Thanh Hoang, Won Ho Choi, Martin Lueker-Boden
  • Publication number: 20210110244
    Abstract: Use of a NAND array architecture to realize a binary neural network (BNN) allows for matrix multiplication and accumulation to be performed within the memory array. A unit synapse for storing a weight of a BNN is stored in a pair of series connected memory cells. A binary input is applied on a pair of word lines connected to the unit synapse to perform the multiplication of the input with the weight. The results of such multiplications are determined by a sense amplifier, with the results accumulated by a counter. The arrangement extends to ternary inputs to realize a ternary-binary network (TBN) by adding a circuit to detect 0 input values and adjust the accumulated count accordingly. The arrangement further extends to a ternary-ternary network (TTN) by allowing 0 weight values in a unit synapse, maintaining the number of 0 weights in a register, and adjusting the count accordingly.
    Type: Application
    Filed: October 15, 2019
    Publication date: April 15, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Tung Thanh Hoang, Won Ho Choi, Martin Lueker-Boden
  • Publication number: 20210098041
    Abstract: A system and method include determining, by a memory controller associated with a memory device, a value of a parameter of a write pulse for a plurality of bits of a B-bit word to be stored in the memory device. The value of the parameter is based upon a relative importance of a bit position of the plurality of bits in the B-bit word to a performance of a machine learning or signal processing task involving the B-bit word, a fidelity metric, and a resource metric. The system and method also include writing each of the plurality of bits of the B-bit word in a different sub-array of the memory device using the write pulse generated based on the value of the parameter determined for a particular one of the plurality of bits.
    Type: Application
    Filed: September 27, 2019
    Publication date: April 1, 2021
    Applicant: Western Digital Technologies, Inc.
    Inventors: Yongjune Kim, Yoocharn Jeon, Won Ho Choi, Cyril Guyot, Yuval Cassuto
  • Publication number: 20210083173
    Abstract: Apparatuses, systems, and methods are disclosed for magnetoresistive random access memory. A magnetic tunnel junction (MTJ) for storing data may include a reference layer. A free layer of an MTJ may be separated from a reference layer by a barrier layer. A free layer may be configured such that one or more resistance states for an MTJ correspond to one or more positions of a magnetic domain wall within the free layer. A domain stabilization layer may be coupled to a portion of a free layer, and may be configured to prevent migration of a domain wall into the portion of the free layer.
    Type: Application
    Filed: December 2, 2020
    Publication date: March 18, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Young-Suk Choi, Won Ho Choi