Patents by Inventor Scott C. Lewis

Scott C. Lewis 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: 11152063
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: July 30, 2019
    Date of Patent: October 19, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 11056185
    Abstract: A system and method are shown for both forward and reverse read operations in a neuromorphic crossbar array that is part of an artificial neural network (ANN). During a forward read operation, a plurality of neuron activations are encoded into a pulse width drive array word line that gates a cell access transistor. A source-follower transistor is biased at a source follower voltage (VRDP) and a column voltage node (BLV) is held at read voltage (VREAD). During a reverse read operation, the cell access transistor operates as another source follower by: encoding a neuron error signal into the column voltage node (BLV), driving a gate line of the cell access transistor to the source follower voltage (VRDP), and holding an intermediate node between the cell access transistor of (a) and the source-follower transistor of (b) at the read voltage (VREAD).
    Type: Grant
    Filed: October 12, 2018
    Date of Patent: July 6, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Pritish Narayanan, Scott C Lewis
  • Patent number: 10998045
    Abstract: Structures and methods for a multi-bit phase change memory are provided herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: November 11, 2019
    Date of Patent: May 4, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10943658
    Abstract: Structures and methods for a multi-bit phase change memory, are provided herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: November 11, 2019
    Date of Patent: March 9, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10937496
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: July 30, 2019
    Date of Patent: March 2, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10810489
    Abstract: A neuromorphic memory system including neuromorphic memory arrays. The neuromorphic memory system includes a presynaptic neuron circuit coupled to a postsynaptic neuron circuit by a resistive memory cell. The method includes generating a presynaptic LIF pulse on a presynaptic LIF line at time t1. An activating operation activates an access transistor coupled to the presynaptic LIF line in response to the presynaptic LIF pulse. The access transistor enables LIF current to pass through the resistive memory cell to a postsynaptic LIF line. An integrating operation integrates the LIF current at the postsynaptic LIF line over time. A comparing operation compares a LIF voltage at the postsynaptic LIF line to a threshold voltage. A generating operation generates a postsynaptic spike timing dependent plasticity (STDP) pulse on a postsynaptic STDP line if the LIF voltage is beyond the threshold voltage.
    Type: Grant
    Filed: November 12, 2019
    Date of Patent: October 20, 2020
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kohji Hosokawa, Masatoshi Ishii, SangBum Kim, Chung H. Lam, Scott C. Lewis
  • Patent number: 10762959
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: May 25, 2018
    Date of Patent: September 1, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10692576
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: June 23, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Publication number: 20200118619
    Abstract: A system and method are shown for both forward and reverse read operations in a neuromorphic crossbar array that is part of an artificial neural network (ANN). During a forward read operation, a plurality of neuron activations are encoded into a pulse width drive array word line that gates a cell access transistor. A source-follower transistor is biased at a source follower voltage (VRDP) and a column voltage node (BLV) is held at read voltage (VREAD). During a reverse read operation, the cell access transistor operates as another source follower by: encoding a neuron error signal into the column voltage node (BLV), driving a gate line of the cell access transistor to the source follower voltage (VRDP), and holding an intermediate node between the cell access transistor of (a) and the source-follower transistor of (b) at the read voltage (VREAD).
    Type: Application
    Filed: October 12, 2018
    Publication date: April 16, 2020
    Inventors: PRITISH NARAYANAN, SCOTT C. LEWIS
  • Publication number: 20200082256
    Abstract: A neuromorphic memory system including neuromorphic memory arrays. The neuromorphic memory system includes a presynaptic neuron circuit coupled to a postsynaptic neuron circuit by a resistive memory cell. The method includes generating a presynaptic LIF pulse on a presynaptic LIF line at time t1. An activating operation activates an access transistor coupled to the presynaptic LIF line in response to the presynaptic LIF pulse. The access transistor enables LIF current to pass through the resistive memory cell to a postsynaptic LIF line. An integrating operation integrates the LIF current at the postsynaptic LIF line over time. A comparing operation compares a LIF voltage at the postsynaptic LIF line to a threshold voltage. A generating operation generates a postsynaptic spike timing dependent plasticity (STDP) pulse on a postsynaptic STDP line if the LIF voltage is beyond the threshold voltage.
    Type: Application
    Filed: November 12, 2019
    Publication date: March 12, 2020
    Inventors: Kohji Hosokawa, Masatoshi Ishii, SangBum Kim, Chung H. Lam, Scott C. Lewis
  • Publication number: 20200075097
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: November 11, 2019
    Publication date: March 5, 2020
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Publication number: 20200075096
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: November 11, 2019
    Publication date: March 5, 2020
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10572799
    Abstract: A neuromorphic memory system including neuromorphic memory arrays. The neuromorphic memory system includes a presynaptic neuron circuit coupled to a postsynaptic neuron circuit by a resistive memory cell. The method includes generating a presynaptic LIF pulse on a presynaptic LIF line at time t1. An activating operation activates an access transistor coupled to the presynaptic LIF line in response to the presynaptic LIF pulse. The access transistor enables LIF current to pass through the resistive memory cell to a postsynaptic LIF line. An integrating operation integrates the LIF current at the postsynaptic LIF line over time. A comparing operation compares a LIF voltage at the postsynaptic LIF line to a threshold voltage. A generating operation generates a postsynaptic spike timing dependent plasticity (STDP) pulse on a postsynaptic STDP line if the LIF voltage is beyond the threshold voltage.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: February 25, 2020
    Assignee: International Business Machines Corporation
    Inventors: Kohji Hosokawa, Masatoshi Ishii, SangBum Kim, Chung H. Lam, Scott C. Lewis
  • Patent number: 10566057
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: February 18, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Patent number: 10535403
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: May 25, 2018
    Date of Patent: January 14, 2020
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Publication number: 20190355417
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: July 30, 2019
    Publication date: November 21, 2019
    Inventors: Chung H. LAM, Scott C. LEWIS, Thomas M. MAFFITT, Jack MORRISH
  • Publication number: 20190355416
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: July 30, 2019
    Publication date: November 21, 2019
    Inventors: Chung H. LAM, Scott C. LEWIS, Thomas M. MAFFITT, Jack MORRISH
  • Patent number: 10424375
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Grant
    Filed: November 14, 2017
    Date of Patent: September 24, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Chung H. Lam, Scott C. Lewis, Thomas M. Maffitt, Jack Morrish
  • Publication number: 20190267087
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: May 14, 2019
    Publication date: August 29, 2019
    Inventors: Chung H. LAM, Scott C. LEWIS, Thomas M. MAFFITT, Jack MORRISH
  • Publication number: 20190267086
    Abstract: Structures and methods for a multi-bit phase change memory are disclosed herein. A method includes establishing a write-reference voltage that incrementally ramps over a write period. The increments of the write-reference voltage correspond to discrete resistance states of a storage cell of the multi-bit phase change memory.
    Type: Application
    Filed: May 14, 2019
    Publication date: August 29, 2019
    Inventors: Chung H. LAM, Scott C. LEWIS, Thomas M. MAFFITT, Jack MORRISH