Patents by Inventor Kendrick H. Yuen

Kendrick H. Yuen 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: 9799824
    Abstract: A memory cell includes an elongated first electrode coupled to a magnetic tunnel junction (MTJ) structure and an elongated second electrode aligned with the elongated first electrode coupled to the MTJ structure. The elongated electrodes are configured to direct mutually additive portions of a switching current induced magnetic field through the MTJ. The mutually additive portions enhance switching of the MTJ in response to application of the switching current.
    Type: Grant
    Filed: June 1, 2016
    Date of Patent: October 24, 2017
    Assignee: QUALCOMM Incorporated
    Inventors: William H. Xia, Wenqing Wu, Kendrick H. Yuen, Abhishek Banerjee, Xia Li, Seung H. Kang, Jung Pill Kim
  • Publication number: 20160276576
    Abstract: A memory cell includes an elongated first electrode coupled to a magnetic tunnel junction (MTJ) structure and an elongated second electrode aligned with the elongated first electrode coupled to the MTJ structure. The elongated electrodes are configured to direct mutually additive portions of a switching current induced magnetic field through the MTJ. The mutually additive portions enhance switching of the MTJ in response to application of the switching current.
    Type: Application
    Filed: June 1, 2016
    Publication date: September 22, 2016
    Inventors: William H. XIA, Wenqing WU, Kendrick H. YUEN, Abhishek BANERJEE, Xia LI, Seung H. KANG, Jung Pill KIM
  • Patent number: 9385305
    Abstract: A memory cell includes an elongated first electrode coupled to a magnetic tunnel junction (MTJ) structure and an elongated second electrode aligned with the elongated first electrode coupled to the MTJ structure. The elongated electrodes are configured to direct mutually additive portions of a switching current induced magnetic field through the MTJ. The mutually additive portions enhance switching of the MTJ in response to application of the switching current.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: July 5, 2016
    Assignee: QUALCOMM INCORPORATED
    Inventors: William H. Xia, Wenqing Wu, Kendrick H. Yuen, Abhishek Banerjee, Xia Li, Seung H. Kang, Jung Pill Kim
  • Patent number: 9164729
    Abstract: A method and apparatus for generating random binary sequences from a physical entropy source having a state A and a state B by detecting whether the physical entropy source is in the state A or in the state B, attempting to shift the state of the physical entropy source to the opposite state in a probabilistic manner with less than 100% certainty, and producing one of four outputs based on the detected state and the state of the physical entropy source before the attempted shift. The outputs are placed in first and second queues and extracted in pairs from each queue. Random binary bits are output based on the sequences extracted from each queue.
    Type: Grant
    Filed: February 5, 2013
    Date of Patent: October 20, 2015
    Assignee: QUALCOMM INCORPORATED
    Inventors: Wenqing Wu, Peiyuan Wang, Raghu Sagar Madala, Senthil Kumar Govindaswamy, Kendrick H. Yuen, Robert P. Gilmore, Jung Pill Kim, Seung H. Kang
  • Patent number: 9147454
    Abstract: A magnetic tunneling junction non-volatile register with feedback for robust read and write operations. In an embodiment, two MTJ devices are configured to store a logical 0 or a logical 1, and are coupled to drive an output node to a voltage indicative of the stored logical 0 or a logical 1. The output of a D flip-flop is fed to the two MTJ devices so that the state of the D flip-flop may be stored in the two MTJ devices during a store operation. During a read operation, the D flip-flop outputs the state of the two MTJ devices. Read disturbances are mitigated with the use of an edge detector coupled to the output node, so that a LOW voltage is provided to the D flip-flop if a rising voltage at the output node is detected.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: September 29, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Zhenyu Sun, Raghu Sagar Madala, Senthil Kumar Govindaswamy, Kendrick H. Yuen, Wenqing Wu, Peiyuan Wang
  • Patent number: 9110746
    Abstract: Embodiments of the disclosure are directed to generating a random number. An embodiment of the disclosure passes a current from a read operation through a magnetic tunnel junction (MTJ) to cause a first magnetization orientation of a free layer to switch to a second magnetization orientation, the switch in magnetization orientation causing a change in a resistance of the MTJ, and periodically samples the resistance of the MTJ to generate a bit value for the random number.
    Type: Grant
    Filed: September 4, 2012
    Date of Patent: August 18, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Xiaochun Zhu, Wenqing Wu, David M. Jacobson, Seung H. Kang, Kendrick H. Yuen
  • Patent number: 9053071
    Abstract: Sensor circuitry including probabilistic switching devices, such as spin-transfer torque magnetic tunnel junctions (STT-MTJs), is configured to perform ultra-low power analog to digital conversion and compressive sensing. The analog to digital conversion and compressive sensing processes are performed simultaneously and in a manner that is native to the devices due to their probabilistic switching characteristics.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: June 9, 2015
    Assignee: QUALCOMM, Incorporated
    Inventors: Abhishek Banerjee, Raghu Sagar Madala, Wenqing Wu, Kendrick H. Yuen, Chengzhi Pan
  • Publication number: 20140231940
    Abstract: A memory cell includes an elongated first electrode coupled to a magnetic tunnel junction (MTJ) structure and an elongated second electrode aligned with the elongated first electrode coupled to the MTJ structure. The elongated electrodes are configured to direct mutually additive portions of a switching current induced magnetic field through the MTJ. The mutually additive portions enhance switching of the MTJ in response to application of the switching current.
    Type: Application
    Filed: February 19, 2013
    Publication date: August 21, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: William H. Xia, Wenqing Wu, Kendrick H. Yuen, Abhishek Banerjee, Xia Li, Seung H. Kang, Jung Pill Kim
  • Patent number: 8804413
    Abstract: A multi-free layer magnetic tunnel junction (MTJ) cell includes a bottom electrode layer, an anti-ferromagnetic layer on the bottom electrode layer, a fixed magnetization layer on the anti-ferromagnetic layer and a barrier layer on the fixed magnetization layer. A first free magnetization layer is on a first area of the barrier layer, and a capping layer is on the first free magnetization layer. A free magnetization layer is on a second area of the barrier layer, laterally displaced from the first area, and a capping layer is on the second free magnetization layer. Optionally current switches establish a read current path including the first free magnetization layer concurrent with not establishing a read current path including the second free magnetization layer. Optionally current switches establishing a read current path including the first and second free magnetization layer.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: August 12, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xia Li, Wenqing Wu, Jung Pill Kim, Xiaochun Zhu, Seung H. Kang, Raghu Sagar Madala, Kendrick H. Yuen
  • Publication number: 20140222880
    Abstract: A method and apparatus for generating random binary sequences from a physical entropy source having a state A and a state B by detecting whether the physical entropy source is in the state A or in the state B, attempting to shift the state of the physical entropy source to the opposite state in a probabilistic manner with less than 100% certainty, and producing one of four outputs based on the detected state and the state of the physical entropy source before the attempted shift. The outputs are placed in first and second queues and extracted in pairs from each queue. Random binary bits are output based on the sequences extracted from each queue.
    Type: Application
    Filed: February 5, 2013
    Publication date: August 7, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Wenqing Wu, Peiyuan Wang, Raghu Sagar Madala, Senthil Kumar Govindaswamy, Kendrick H. Yuen, Robert P. Gilmore, Jung Pill Kim, Seung H. Kang
  • Publication number: 20140198563
    Abstract: A magnetic tunneling junction non-volatile register with feedback for robust read and write operations. In an embodiment, two MTJ devices are configured to store a logical 0 or a logical 1, and are coupled to drive an output node to a voltage indicative of the stored logical 0 or a logical 1. The output of a D flip-flop is fed to the two MTJ devices so that the state of the D flip-flop may be stored in the two MTJ devices during a store operation. During a read operation, the D flip-flop outputs the state of the two MTJ devices. Read disturbances are mitigated with the use of an edge detector coupled to the output node, so that a LOW voltage is provided to the D flip-flop if a rising voltage at the output node is detected.
    Type: Application
    Filed: March 11, 2013
    Publication date: July 17, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Zhenyu Sun, Raghu Sagar Madala, Senthil Kumar Govindaswamy, Kendrick H. Yuen, Wenqing Wu, Peiyuan Wang
  • Patent number: 8779824
    Abstract: Clock signals are distributed on a chip by applying an oscillating magnetic field to the chip. Local clock generation circuits including magnetic field sensors are distributed around the chip and are coupled to local clocked circuitry on the chip. The magnetic field sensors may include clock magnetic tunnel junctions (MTJs) in which a magnetic orientation of the free layer is free to rotate in the free layer plane in response to the applied magnetic field. The MTJ resistance alternates between a high resistance value and a low resistance value as the free layer magnetization rotates. Clock generation circuitry coupled to the clock MTJs senses voltage oscillations caused by the alternating resistance of the clock MTJs. The clock generation circuitry includes amplifiers, which convert the sensed voltage into local clock signals.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: July 15, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Wenqing Wu, Kendrick H. Yuen, David W. Hansquine, Robert P. Gilmore, Jeff A. Levin
  • Publication number: 20140167831
    Abstract: Clock signals are distributed on a chip by applying an oscillating magnetic field to the chip. Local clock generation circuits including magnetic field sensors are distributed around the chip and are coupled to local clocked circuitry on the chip. The magnetic field sensors may include clock magnetic tunnel junctions (MTJs) in which a magnetic orientation of the free layer is free to rotate in the free layer plane in response to the applied magnetic field. The MTJ resistance alternates between a high resistance value and a low resistance value as the free layer magnetization rotates. Clock generation circuitry coupled to the clock MTJs senses voltage oscillations caused by the alternating resistance of the clock MTJs. The clock generation circuitry includes amplifiers, which convert the sensed voltage into local clock signals.
    Type: Application
    Filed: December 17, 2012
    Publication date: June 19, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Wenqing Wu, Kendrick H. Yuen, David W. Hansquine, Robert P. Gilmore, Jeff A. Levin
  • Publication number: 20140067890
    Abstract: Embodiments of the disclosure are directed to generating a random number. An embodiment of the disclosure passes a current from a read operation through a magnetic tunnel junction (MTJ) to cause a first magnetization orientation of a free layer to switch to a second magnetization orientation, the switch in magnetization orientation causing a change in a resistance of the MTJ, and periodically samples the resistance of the MTJ to generate a bit value for the random number.
    Type: Application
    Filed: September 4, 2012
    Publication date: March 6, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Xiaochun Zhu, Wenqing Wu, David M. Jacobson, Seung H. Kang, Kendrick H. Yuen
  • Patent number: 8625337
    Abstract: A probabilistic programming current is injected into a cluster of bi-stable probabilistic switching elements, the probabilistic programming current having parameters set to result in a less than unity probability of any given bi-stable switching element switching, and a resistance of the cluster of bi-stable switching elements is detected. The probabilistic programming current is injected and the resistance of the cluster state detected until a termination condition is met. Optionally the termination condition is detecting the resistance of the cluster of bi-stable switching elements at a value representing a multi-bit data.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: January 7, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Wenqing Wu, Kendrick H. Yuen, Xiaochun Zhu, Seung H. Kang, Matthew Michael Nowak, Jeffrey A. Levin, Robert Gilmore, Nicholas Yu
  • Publication number: 20130245999
    Abstract: Sensor circuitry including probabilistic switching devices, such as spin-transfer torque magnetic tunnel junctions (STT-MTJs), is configured to perform ultra-low power analog to digital conversion and compressive sensing. The analog to digital conversion and compressive sensing processes are performed simultaneously and in a manner that is native to the devices due to their probabilistic switching characteristics.
    Type: Application
    Filed: March 15, 2012
    Publication date: September 19, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Abhishek Banerjee, Raghu Sagar Madala, Wenqing Wu, Kendrick H. Yuen, Chengzhi Pan
  • Publication number: 20130201757
    Abstract: A multi-free layer magnetic tunnel junction (MTJ) cell includes a bottom electrode layer, an anti-ferromagnetic layer on the bottom electrode layer, a fixed magnetization layer on the anti-ferromagnetic layer and a barrier layer on the fixed magnetization layer. A first free magnetization layer is on a first area of the barrier layer, and a capping layer is on the first free magnetization layer. A free magnetization layer is on a second area of the barrier layer, laterally displaced from the first area, and a capping layer is on the second free magnetization layer. Optionally current switches establish a read current path including the first free magnetization layer concurrent with not establishing a read current path including the second free magnetization layer. Optionally current switches establishing a read current path including the first and second free magnetization layer.
    Type: Application
    Filed: August 16, 2012
    Publication date: August 8, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Xia Li, Wenqing Wu, Jung Pill Kim, Xiaochun Zhu, Seung H. Kang, Raghu Sagar Madala, Kendrick H. Yuen
  • Publication number: 20130187247
    Abstract: A spin-torque transfer (STT) magnetic tunnel junction (MTJ) memory includes a unitary fixed magnetic layer, a magnetic barrier layer on the unitary fixed magnetic layer, a free magnetic layer having a plurality of free magnetic islands on the magnetic barrier layer, and a cap layer overlying the free magnetic layer. Also a method of forming an STT-MTJ memory.
    Type: Application
    Filed: January 23, 2012
    Publication date: July 25, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Wenqing WU, Sean Li, Xiaochun Zhu, Raghu Sagar Madala, Seung H. Kang, Kendrick H. Yuen
  • Publication number: 20110273926
    Abstract: A probabilistic programming current is injected into a cluster of bi-stable probabilistic switching elements, the probabilistic programming current having parameters set to result in a less than unity probability of any given bi-stable switching element switching, and a resistance of the cluster of bi-stable switching elements is detected. The probabilistic programming current is injected and the resistance of the cluster state detected until a termination condition is met. Optionally the termination condition is detecting the resistance of the cluster of bi-stable switching elements at a value representing a multi-bit data.
    Type: Application
    Filed: May 5, 2011
    Publication date: November 10, 2011
    Applicant: QUALCOMM INCORPORATED
    Inventors: Wenqing Wu, Kendrick H. Yuen, Xiaochun Zhu, Seung H. Kang, Matthew Michael Nowak, Jeffrey A. Levin, Robert Gilmore, Nicholas Yu