Patents by Inventor David W. Boerstler

David W. Boerstler 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: 7642863
    Abstract: Systems and methods for enabling the determination of voltage controlled oscillator (VCO) linearity, duty cycle determination and duty cycle correction in phase locked loop circuits (PLL's.) One embodiment comprises a method including the steps of determining the frequency response of a PLL's VCO as a function of duty cycle, applying a signal based on the VCO output to the VCO input, measuring the resulting frequency of the VCO output signal, determining the duty cycle corresponding to the measured frequency, and configuring a duty cycle correction unit correct the duty cycle of the VCO output signal to about 50%. Determining the frequency response of the VCO may include, for each of several different duty cycle values between 0% and 100%, applying the VCO input signal to the VCO and determining the corresponding frequency of the VCO output signal. This may also be done for duty cycles of 0% and 100%.
    Type: Grant
    Filed: December 7, 2007
    Date of Patent: January 5, 2010
    Assignees: Kabushiki Kaisha Toshiba, International Business Machines Corporation
    Inventors: Masaaki Kaneko, David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Publication number: 20090285344
    Abstract: Mechanisms are provided for compensating for process and temperature variations in a circuit. The mechanisms may select at least one resistor in a plurality of resistors in the circuit to provide a resistance value for generating a calibration voltage input to the circuit to compensate for variations in process. A reference signal may be compared to a feedback signal generated by the circuit based on the calibration signal. A determination is made as to whether the feedback signal is within a tolerance of the reference signal and, if so, an identifier of the selected at least one resistor is stored in a memory device coupled to the circuit. The circuit may be operated using the selected at least one resistor based on the identifier stored in the memory device. An apparatus and integrated circuit device utilizing these mechanisms are also provided.
    Type: Application
    Filed: May 14, 2008
    Publication date: November 19, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: David W. Boerstler, Masaaki Kaneko, Toshiyuki Ogata, Jieming Qi
  • Publication number: 20090183136
    Abstract: A design structure for a programmable interpolative voltage controlled oscillator (VCO) with adjustable frequency range output is provided. Programmable delay cells whose size is modifiable based on control inputs to the programmable delay cells are utilized. A different set of control inputs may be provided to programmable delay cells of an inner sub-ring from the set of control inputs provided to programmable delay cells of a main ring of the VCO. The minimum frequency output of the VCO is governed by the main ring programmable delay cell strength with the maximum frequency output of the VCO being governed by a ratio of strengths of the main ring programmable delay cells to the inner sub-ring programmable delay cell. By modifying the control inputs to the inner sub-ring and main ring programmable delay cells, the minimum and maximum frequency outputs, and thus the range between these two frequency outputs, are made programmable.
    Type: Application
    Filed: May 30, 2008
    Publication date: July 16, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi
  • Publication number: 20090146743
    Abstract: Systems and methods for enabling the determination of voltage controlled oscillator (VCO) linearity, duty cycle determination and duty cycle correction in phase locked loop circuits (PLL's.) One embodiment comprises a method including the steps of determining the frequency response of a PLL's VCO as a function of duty cycle, applying a signal based on the VCO output to the VCO input, measuring the resulting frequency of the VCO output signal, determining the duty cycle corresponding to the measured frequency, and configuring a duty cycle correction unit correct the duty cycle of the VCO output signal to about 50%. Determining the frequency response of the VCO may include, for each of several different duty cycle values between 0% and 100%, applying the VCO input signal to the VCO and determining the corresponding frequency of the VCO output signal. This may also be done for duty cycles of 0% and 100%.
    Type: Application
    Filed: December 7, 2007
    Publication date: June 11, 2009
    Inventors: Masaaki Kaneko, David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Publication number: 20090138834
    Abstract: A design structure for a circuit for measuring the absolute duty cycle of a signal anywhere on an integrated circuit device is provided. The circuit has a plurality of substantially identical pulse shaper elements, each of which expand the pulse of an input signal whose duty cycle is to be measured by a same amount. The outputs of the pulse shaper elements may be coupled to substantially identical divider circuits whose outputs are coupled to a multiplexer that selects two inputs for output to a set of master/slave configured flip-flops, one input serving as a clock and the other as data to the flip-flops. The flip-flops sample the divider outputs selected by the multiplexer to detect if the dividers have failed or not. The outputs of the flip-flops are provided to an XOR gate which outputs a duty cycle signal indicative of the duty cycle of the input signal.
    Type: Application
    Filed: May 30, 2008
    Publication date: May 28, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi, Bin Wan
  • Publication number: 20090128133
    Abstract: A method and apparatus for measuring the absolute duty cycle of a signal anywhere on an integrated circuit device are provided. The mechanism employs a circuit having a plurality of substantially identical pulse shaper elements, each of which expand the pulse of an input signal whose duty cycle is to be measured by a same amount. The outputs of the pulse shaper elements may be coupled to substantially identical divider circuits whose outputs are coupled to a multiplexer that selects two inputs for output to a set of master/slave configured flip-flops, one input serving as a clock and the other as data to the flip-flops. The flip-flops sample the divider outputs selected by the multiplexer to detect if the dividers have failed or not. The outputs of the flip-flops are provided to an XOR gate which outputs a duty cycle signal indicative of the duty cycle of the input signal.
    Type: Application
    Filed: November 20, 2007
    Publication date: May 21, 2009
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi, Bin Wan
  • Publication number: 20090128206
    Abstract: An apparatus and method for obtaining a desired phase locked loop (PLL) duty cycle without a pre-scaler are provided. The PLL circuit of the illustrative embodiments utilizes two separate loops that simultaneously operate on the VCO. One loop ensures the frequency and phase lock while the other loop ensures the duty cycle lock. The VCO is modified to have an additional control port to adjust the duty cycle. Thus, the VCO has one control port for performing frequency adjustment and one control port for duty cycle adjustment. As a result, both the duty cycle and the frequency may be controlled using the VCO of the PLL circuit of the illustrative embodiments so as to achieve any desired duty cycle output without requiring a VCO pre-scaler circuit or duty cycle correction circuit.
    Type: Application
    Filed: November 20, 2007
    Publication date: May 21, 2009
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi
  • Publication number: 20090132971
    Abstract: A design structure for a circuit for obtaining a desired phase locked loop (PLL) duty cycle without a pre-scaler is provided. The PLL circuit of the illustrative embodiments utilizes two separate loops that simultaneously operate on the VCO. One loop ensures the frequency and phase lock while the other loop ensures the duty cycle lock. The VCO is modified to have an additional control port to adjust the duty cycle. Thus, the VCO has one control port for performing frequency adjustment and one control port for duty cycle adjustment. As a result, both the duty cycle and the frequency may be controlled using the VCO of the PLL circuit of the illustrative embodiments so as to achieve any desired duty cycle output without requiring a VCO pre-scaler circuit or duty cycle correction circuit.
    Type: Application
    Filed: May 30, 2008
    Publication date: May 21, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi
  • Publication number: 20090125262
    Abstract: A method and apparatus for measuring the absolute duty cycle of a signal are provided. A non-inverted path from a signal source is selected and various DCC circuit setting indices are cycled through until a divider, coupled to the output of the DCC circuit, fails. A first minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of the failure. An inverted path from the signal source is selected and the various DCC circuit setting indices are cycled through again until the divider fails. A second minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of this second failure. The duty cycle is then calculated based on a difference of the first and second minimum pulse width values.
    Type: Application
    Filed: November 12, 2007
    Publication date: May 14, 2009
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi, Bin Wan
  • Publication number: 20090125857
    Abstract: A design structure for a circuit for measuring the absolute duty cycle of a signal, is provided. A non-inverted path from a signal source is selected and various DCC circuit setting indices are cycled through until a divider, coupled to the output of the DCC circuit, fails. A first minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of the failure. An inverted path from the signal source is selected and the various DCC circuit setting indices are cycled through again until the divider fails. A second minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of this second failure. The duty cycle is then calculated based on a difference of the first and second minimum pulse width values.
    Type: Application
    Filed: May 30, 2008
    Publication date: May 14, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi, Bin Wan
  • Patent number: 7519498
    Abstract: The present invention provides a method, an apparatus, and a computer program product for measuring the temperature of a microprocessor through the use of ESD circuitry. The present invention uses diodes and an I/O pad within ESD circuits to determine the temperature at the location of the ESD circuitry. First, a current measuring device connects to a diode. A user or a computer program disables the protected component or circuitry, and subsequently applies a predetermined voltage to the I/O pad. This creates a reverse saturation current through the diode, which is measured by the current measuring device. From this current the user or a computer program determines the temperature of the microprocessor at the diode through the use of a graphical representation of diode reverse saturation current and corresponding temperature.
    Type: Grant
    Filed: October 4, 2005
    Date of Patent: April 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Kazuhiko Miki, Jieming Qi
  • Patent number: 7511554
    Abstract: Systems and methods for conveying signals between integrated circuit (IC) components in domains having different supply voltages. AC coupling is used to increase the speed at which the common mode voltage of a signal is shifted from one level to another. One embodiment comprises a method for level shifting a binary signal in an IC. This method includes receiving an input binary signal and decoupling its AC component from its common mode component. A second common mode component is added to the AC component, providing a binary output signal. The common mode voltage of the input signal may be greater (or smaller) than that of the output signal. In one embodiment of the method, duty cycle compensation (DCC) is performed. The DCC drives the duty cycle toward a desired value.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: March 31, 2009
    Assignees: Kabushiki Kaisha Toshiba, International Business Machines Corporation
    Inventors: Masaaki Kaneko, David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Publication number: 20090066424
    Abstract: A programmable interpolative voltage controlled oscillator (VCO) with adjustable frequency range output is provided. With the VCO, programmable delay cells whose size is modifiable based on control inputs to the programmable delay cells are utilized. A different set of control inputs may be provided to programmable delay cells of an inner sub-ring from the set of control inputs provided to programmable delay cells of a main ring of the VCO. The minimum frequency output of the VCO is governed by the main ring programmable delay cell strength with the maximum frequency output of the VCO being governed by a ratio of strengths of the main ring programmable delay cells to the inner sub-ring programmable delay cell. By modifying the control inputs to the inner sub-ring and main ring programmable delay cells, the minimum and maximum frequency outputs, and thus the range between these two frequency outputs, are made programmable.
    Type: Application
    Filed: September 12, 2007
    Publication date: March 12, 2009
    Inventors: David W. Boerstler, Eskinder Hailu, Masaaki Kaneko, Jieming Qi
  • Patent number: 7493229
    Abstract: A mechanism for utilizing a single set of one or more thermal sensors, e.g., thermal diodes, provided on the integrated circuit device, chip, etc., to control the operation of the integrated circuit device, associated cooling system, and high-frequency PLLs is provided. By utilizing a single set of thermal sensors to provide multiple functions, e.g., controlling the operation of the integrated circuit device, the cooling system, and the PLLs, silicon real-estate usage is reduced through combining circuitry functionality. Moreover, the integrated circuit device yield is improved by reducing circuitry complexity and increasing PLL robustness to temperature. Furthermore, the PLL circuitry operating range is improved by compensating for temperature.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: February 17, 2009
    Assignee: International Business Machines Corporation
    Inventors: David W. Boerstler, Nathaniel R. Chadwick, Eskinder Hailu, Kirk D. Peterson, Jieming Qi
  • Publication number: 20090024349
    Abstract: A mechanism for utilizing a single set of one or more thermal sensors, e.g., thermal diodes, provided on the integrated circuit device, chip, etc., to control the operation of the integrated circuit device, associated cooling system, and high-frequency PLLs is provided. By utilizing a single set of thermal sensors to provide multiple functions, e.g., controlling the operation of the integrated circuit device, the cooling system, and the PLLs, silicon real-estate usage is reduced through combining circuitry functionality. Moreover, the integrated circuit device yield is improved by reducing circuitry complexity and increasing PLL robustness to temperature. Furthermore, the PLL circuitry operating range is improved by compensating for temperature.
    Type: Application
    Filed: July 20, 2007
    Publication date: January 22, 2009
    Inventors: David W. Boerstler, Nathaniel R. Chadwick, Eskinder Hailu, Kirk D. Peterson, Jieming Qi
  • Publication number: 20090021314
    Abstract: A design structure for an apparatus for utilizing a single set of one or more thermal sensors, e.g., thermal diodes, provided on the integrated circuit device, chip, etc., to control the operation of the integrated circuit device, associated cooling system, and high-frequency PLLs, is provided. By utilizing a single set of thermal sensors to provide multiple functions, e.g., controlling the operation of the integrated circuit device, the cooling system, and the PLLs, silicon real-estate usage is reduced through combining circuitry functionality. Moreover, the integrated circuit device yield is improved by reducing circuitry complexity and increasing PLL robustness to temperature. Furthermore, the PLL circuitry operating range is improved by compensating for temperature.
    Type: Application
    Filed: May 29, 2008
    Publication date: January 22, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Nathaniel R. Chadwick, Eskinder Hailu, Kirk D. Peterson, Jieming Qi
  • Publication number: 20090007047
    Abstract: A design structure for a hybrid phase locked loop (PLL) circuit that obtains stabilized dynamic response and independent adjustment of damping factor and loop bandwidth is provided. The hybrid PLL circuit of the illustrative embodiments includes the resistance/capacitance (RC) filter elements of a conventional RC PLL and the feed-forward path from the output of the phase frequency detector to the voltage controlled oscillator (VCO). The hybrid PLL essentially enhances the performance of the conventional feed-forward PLL by providing the RC filter whose components can be weighted to provide a dynamic response that is significantly less sensitive to parameter variation and which allows loop bandwidth optimization without sacrificing damping.
    Type: Application
    Filed: May 29, 2008
    Publication date: January 1, 2009
    Applicant: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Publication number: 20090002038
    Abstract: A hybrid phase locked loop (PLL) circuit for obtaining stabilized dynamic response and independent adjustment of damping factor and loop bandwidth is provided. The hybrid PLL circuit of the illustrative embodiments includes the resistance/capacitance (RC) filter elements of a conventional RC PLL and the feed-forward path from the output of the phase frequency detector to the voltage controlled oscillator (VCO). The hybrid PLL essentially enhances the performance of the conventional feed-forward PLL by providing the RC filter whose components can be weighted to provide a dynamic response that is significantly less sensitive to parameter variation and which allows loop bandwidth optimization without sacrificing damping.
    Type: Application
    Filed: June 29, 2007
    Publication date: January 1, 2009
    Inventors: David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Publication number: 20080309395
    Abstract: Systems and methods for conveying signals between integrated circuit (IC) components in domains having different supply voltages. AC coupling is used to increase the speed at which the common mode voltage of a signal is shifted from one level to another. One embodiment comprises a method for level shifting a binary signal in an IC. This method includes receiving an input binary signal and decoupling its AC component from its common mode component. A second common mode component is added to the AC component, providing a binary output signal. The common mode voltage of the input signal may be greater (or smaller) than that of the output signal. In one embodiment of the method, duty cycle compensation (DCC) is performed. The DCC drives the duty cycle toward a desired value.
    Type: Application
    Filed: June 18, 2007
    Publication date: December 18, 2008
    Inventors: Masaaki Kaneko, David W. Boerstler, Eskinder Hailu, Jieming Qi
  • Patent number: 7446588
    Abstract: In a first aspect, a first method is provided that includes providing a plurality of select signals and a plurality of input signals for input by a multiplexer. Each select signal is adapted to cause the multiplexer to select a different one of the plurality of input signals for output by the multiplexer when the select signal is in a first logic state. The first method further includes preventing a first of the select signals that is in the first logic state from being provided to the multiplexer until the other select signals are in a second logic state. Number other aspects are provided.
    Type: Grant
    Filed: December 11, 2003
    Date of Patent: November 4, 2008
    Assignee: International Business Machines Corporation
    Inventors: David W. Boerstler, Eskinder Hailu, H. Peter Hofstee