Patents by Inventor Howard H. Chi

Howard H. Chi 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: 8941405
    Abstract: A FET pair based physically unclonable function (PUF) circuit with a constant common mode voltage and methods of use are disclosed. The circuit includes a first n-type field effect transistor (NFET) and a second NFET. The circuit also includes a first load resistor coupled to the first NFET by a first p-type field effect transistor (PFET) and a second load resistor coupled to the second NFET by a second PFET. The circuit further comprises a closed loop, wherein the closed loop creates a constant common mode voltage.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: January 27, 2015
    Assignee: International Business Machines Corporation
    Inventors: Howard H. Chi, Haitao O. Dai, Kai D. Feng, Donald J. Papae
  • Publication number: 20140035670
    Abstract: A FET pair based physically unclonable function (PUF) circuit with a constant common mode voltage and methods of use are disclosed. The circuit includes a first n-type field effect transistor (NFET) and a second NFET. The circuit also includes a first load resistor coupled to the first NFET by a first p-type field effect transistor (PFET) and a second load resistor coupled to the second NFET by a second PFET. The circuit further comprises a closed loop, wherein the closed loop creates a constant common mode voltage.
    Type: Application
    Filed: August 3, 2012
    Publication date: February 6, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Howard H. Chi, Haitao O. Dai, Kai D. Feng, Donald J. Papae
  • Patent number: 8618839
    Abstract: Embodiments of the present invention provide an approach for utilizing a sense amplifier to select a suitable circuit, wherein a suitable circuit generates a voltage that is greater than or equal to a configurable reference voltage. An amplifier gain selector selects a voltage gain of a sense amplifier having input terminals, auxiliary inputs, an output, an array of resistive loads, and the amplifier gain selector. Auxiliary inputs are utilized to nullify direct current (DC) offset voltage of the sense amplifier. Combinatorial logic circuitry connects the input terminals of the sense amplifier to output terminals of a circuit that is within a group of circuits. A comparator circuit determines if the circuit generates a voltage greater than or equal to a configurable reference voltage, based on the output of the sense amplifier.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: December 31, 2013
    Assignee: International Business Machines Corporation
    Inventors: Howard H. Chi, Haitao O. Dai, Kai D. Feng, Donald J. Papae
  • Publication number: 20130241652
    Abstract: Embodiments of the present invention provide an approach for utilizing a sense amplifier to select a suitable circuit, wherein a suitable circuit generates a voltage that is greater than or equal to a configurable reference voltage. An amplifier gain selector selects a voltage gain of a sense amplifier having input terminals, auxiliary inputs, an output, an array of resistive loads, and the amplifier gain selector. Auxiliary inputs are utilized to nullify direct current (DC) offset voltage of the sense amplifier. Combinatorial logic circuitry connects the input terminals of the sense amplifier to output terminals of a circuit that is within a group of circuits. A comparator circuit determines if the circuit generates a voltage greater than or equal to a configurable reference voltage, based on the output of the sense amplifier.
    Type: Application
    Filed: March 13, 2012
    Publication date: September 19, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Howard H. Chi, Haitao O. Dai, Kai D. Feng, Donald J. Papae
  • Patent number: 7688142
    Abstract: A circuit of high performance variable gain amplifier, method of use and design structure on which the subject circuit resides is provided. The circuit comprises a plurality of differential stages having a common input, and output, a common control level input CM and respective individual control level inputs Cx. The circuit also includes a fixed stage that always is biased to an “on” state from the common input.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: March 30, 2010
    Assignee: International Business Machines Corporation
    Inventor: Howard H. Chi
  • Publication number: 20090140809
    Abstract: A circuit of high performance variable gain amplifier, method of use and design structure on which the subject circuit resides is provided. The circuit comprises a plurality of differential stages having a common input, and output, a common control level input CM and respective individual control level inputs Cx. The circuit also includes a fixed stage that always is biased to an “on” state from the common input.
    Type: Application
    Filed: December 3, 2007
    Publication date: June 4, 2009
    Inventor: Howard H. Chi