Patents by Inventor Jianxu Ma

Jianxu Ma 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).

  • Method and apparatus for built-in self-test of CDR and non-CDR components with an on substrate test signal generator
    Patent number: 10641823
    Abstract: An apparatus comprises one or more non-clock and data recovery (CDR) components on a substrate, a signal generator on the substrate and coupled to at least one of the one or more non-CDR components, and a CDR component on the substrate and coupled to the one or more non-CDR components, wherein the CDR component is configured to recover clock data from a received signal by the CDR component, and configured to determine a signal based on the received signal and the clock data.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: May 5, 2020
    Assignee: Photonic Technologies (Shanghai) Co., Ltd.
    Inventors: Ming Lu, Patrick Yin Chiang, Jianxu Ma, Rui Bai, Xuefeng Chen, Juncheng Wang
  • METHOD AND APPARATUS FOR BUILT-IN SELF-TEST
    Publication number: 20200003830
    Abstract: An apparatus comprises one or more non-clock and data recovery (CDR) components on a substrate, a signal generator on the substrate and coupled to at least one of the one or more non-CDR components, and a CDR component on the substrate and coupled to the one or more non-CDR components, wherein the CDR component is configured to recover clock data from a received signal by the CDR component, and configured to determine a signal based on the received signal and the clock data.
    Type: Application
    Filed: March 17, 2017
    Publication date: January 2, 2020
    Inventors: Ming Lu, Patrick Yin Chiang, Jianxu Ma, Rui Bai, Xuefeng Chen, Juncheng Wang
  • Piezo-electric microactuator for dual stage actuator
    Patent number: 7038888
    Abstract: A head flexure assembly having a flexure with a built in microactuator is disclosed. The flexure is divided into four portions: a base plate portion for attaching the flexure to an actuator arm; a load beam portion for suspending a transducing head; a parallelogram portion connecting the load beam portion and the base plate portion and allowing for the translational movement of the load beam portion with respect to the base plate portion; and a driving frame portion. The parallelogram portion has two substantially parallel members that attach the base plate portion to the load beam portion. The parallel members limit the movement of the load beam portion relative to the base plate portion to translational movement. The driving frame portion has piezoelectric element that in response to a control signal produces a force, orthogonal to the flexure's longitudinal axis, between the base plate portion and the load beam portion.
    Type: Grant
    Filed: June 10, 2003
    Date of Patent: May 2, 2006
    Assignee: Seagate Technology LLC
    Inventor: Jianxu Ma
  • Servo flaw detection using PES and velocity thresholds
    Patent number: 6735040
    Abstract: An apparatus and method of identifying defective servo sectors in a data storage device detects servo sectors having an associated position error signal (PES) value that exceeds a predetermined PES threshold value, as well as servo sectors that have a related transducer velocity signal that exceeds a predetermined velocity threshold value.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: May 11, 2004
    Assignee: Seagate Technology LLC
    Inventors: Paul Alexander Galloway, Jianxu Ma, ToaYou Tan, LeokHwa Chua
  • Piezo-electric microactuator for dual stage actuator
    Publication number: 20040021989
    Abstract: A head flexure assembly having a flexure with a built in microactuator is disclosed. The flexure is divided into four portions: a base plate portion for attaching the flexure to an actuator arm; a load beam portion for suspending a transducing head; a parallelogram portion connecting the load beam portion and the base plate portion and allowing for the translational movement of the load beam portion with respect to the base plate portion; and a driving frame portion. The parallelogram portion has two substantially parallel members that attach the base plate portion to the load beam portion. The parallel members limit the movement of the load beam portion relative to the base plate portion to translational movement. The driving frame portion has piezoelectric element that in response to a control signal produces a force, orthogonal to the flexure's longitudinal axis, between the base plate portion and the load beam portion.
    Type: Application
    Filed: June 10, 2003
    Publication date: February 5, 2004
    Inventor: Jianxu Ma
  • Servo flaw detection using PES and velocity thresholds
    Publication number: 20030048570
    Abstract: An apparatus and method of identifying defective servo sectors in a data storage device detects servo sectors having an associated position error signal (PES) value that exceeds a predetermined PES threshold value, as well as servo sectors that have a related transducer velocity signal that exceeds a predetermined velocity threshold value.
    Type: Application
    Filed: December 28, 2001
    Publication date: March 13, 2003
    Inventors: Paul Alexander Galloway, Jianxu Ma, ToaYou Tan, LeokHwa Chua