Patents by Inventor David W. Shan

David W. Shan 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: 9571100
    Abstract: A clock driver is provided. The clock driver includes a multi-stage delay cell having an input, a positive pulse driving branch, a negative pulse driving branch, and an output. The input is for receiving an original version of a reference clock signal input to the clock driver and used to generate a global clock signal. The output is connected to the positive pulse driving branch and the negative pulse driving branch. The clock driver further includes a pulse generator having positive and negative pulse generator portions respectively connected to outputs of the positive and negative pulse driving branches. The pulse generator generates, at any given time, one of a positive pulse and a negative pulse responsive to a positive pulse enable signal and a negative pulse enable signal, respectively, and the original version of the reference clock signal input to the clock driver without modification.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: February 14, 2017
    Assignee: International Business Machines Corporation
    Inventors: Aditya Bansal, Thomas J. Bucelot, Alan J. Drake, Phillip J. Restle, David W. Shan, Mrigank Sharad
  • Publication number: 20160105177
    Abstract: A clock driver is provided. The clock driver includes a multi-stage delay cell having an input, a positive pulse driving branch, a negative pulse driving branch, and an output. The input is for receiving an original version of a reference clock signal input to the clock driver and used to generate a global clock signal. The output is connected to the positive pulse driving branch and the negative pulse driving branch. The clock driver further includes a pulse generator having positive and negative pulse generator portions respectively connected to outputs of the positive and negative pulse driving branches. The pulse generator generates, at any given time, one of a positive pulse and a negative pulse responsive to a positive pulse enable signal and a negative pulse enable signal, respectively, and the original version of the reference clock signal input to the clock driver without modification.
    Type: Application
    Filed: December 17, 2015
    Publication date: April 14, 2016
    Inventors: ADITYA BANSAL, THOMAS J. BUCELOT, ALAN J. DRAKE, PHILLIP J. RESTLE, DAVID W. SHAN, MRIGANK SHARAD
  • Patent number: 9276563
    Abstract: A clock driver and corresponding method are provided. The clock driver includes a multi-stage delay cell having logic circuitry and a plurality of serially connected delay elements. An input of the delay elements receives an original version of a reference clock signal input to the clock driver and used to generate a global clock signal. An output of the delay elements connects to positive and negative pulse driving branches formed from the logic circuitry. The clock driver further includes a pulse generator forming positive and negative pulse generator portions respectively connected to outputs of the positive and negative pulse driving branches. The pulse generator generates, at any given time, one of a positive pulse and a negative pulse responsive to a positive pulse enable signal and a negative pulse enable signal, respectively, and the original version of the reference clock signal input to the clock driver without modification.
    Type: Grant
    Filed: June 13, 2014
    Date of Patent: March 1, 2016
    Assignee: International Business Machines Corporation
    Inventors: Aditya Bansal, Thomas J. Bucelot, Alan J. Drake, Phillip J. Restle, David W. Shan, Mrigank Sharad
  • Publication number: 20150365076
    Abstract: A clock driver and corresponding method are provided. The clock driver includes a multi-stage delay cell having logic circuitry and a plurality of serially connected delay elements. An input of the delay elements receives an original version of a reference clock signal input to the clock driver and used to generate a global clock signal. An output of the delay elements connects to positive and negative pulse driving branches formed from the logic circuitry. The clock driver further includes a pulse generator forming positive and negative pulse generator portions respectively connected to outputs of the positive and negative pulse driving branches. The pulse generator generates, at any given time, one of a positive pulse and a negative pulse responsive to a positive pulse enable signal and a negative pulse enable signal, respectively, and the original version of the reference clock signal input to the clock driver without modification.
    Type: Application
    Filed: June 13, 2014
    Publication date: December 17, 2015
    Inventors: ADITYA BANSAL, THOMAS J. BUCELOT, ALAN J. DRAKE, PHILLIP J. RESTLE, DAVID W. SHAN, MRIGANK SHARAD
  • Patent number: 8027798
    Abstract: A method and apparatus are provided for calibrating digital thermal sensors. A processor chip with a plurality of digital thermal sensors receives an analog voltage. A test circuit coupled to the processor chip receives a clock signal and a register coupled to the test circuit outputs a value on each clock cycle to a digital thermal sensor in the plurality of digital thermal sensors. The digital thermal sensor transitions an output state in response to the value of the register received in the digital thermal sensor equaling a temperature threshold of the digital thermal sensor. The value of the register at the point of transition is used to calibrate the digital thermal sensor. An incrementer increments the value of the register on each clock cycle in response to the value of the register received in the digital thermal sensor failing to equal the temperature threshold of the digital thermal sensor.
    Type: Grant
    Filed: November 8, 2007
    Date of Patent: September 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: Charles R. Johns, Mack W. Riley, David W. Shan, Michael F. Wang
  • Publication number: 20090125267
    Abstract: A method and apparatus are provided for calibrating digital thermal sensors. A processor chip with a plurality of digital thermal sensors receives an analog voltage. A test circuit coupled to the processor chip receives a clock signal and a register coupled to the test circuit outputs a value on each clock cycle to a digital thermal sensor in the plurality of digital thermal sensors. The digital thermal sensor transitions an output state in response to the value of the register received in the digital thermal sensor equaling a temperature threshold of the digital thermal sensor. The value of the register at the point of transition is used to calibrate the digital thermal sensor. An incrementer increments the value of the register on each clock cycle in response to the value of the register received in the digital thermal sensor failing to equal the temperature threshold of the digital thermal sensor.
    Type: Application
    Filed: November 8, 2007
    Publication date: May 14, 2009
    Inventors: Charles R. Johns, Mack W. Riley, David W. Shan, Michael F. Wang