Patents by Inventor Bao G. Truong

Bao G. Truong 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: 9042149
    Abstract: A memory includes an array of memory cells that form rows and columns. The rows of the array include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. The two memory cells of a memory cell pair share a common intra-pair bitline. Adjacent memory cell pairs share a common inter-pair bitline. To perform a data read operation on a particular memory cell in a memory cell pair in the rows and columns of the array, wordline drive circuitry transmits wordline activate signals to select both the row for the data read operation and a particular one of the pair of memory cells for the data read operation.
    Type: Grant
    Filed: December 10, 2013
    Date of Patent: May 26, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michael Ju Hyeok Lee, Bao G Truong
  • Publication number: 20140098590
    Abstract: A memory includes an array of memory cells that form rows and columns. The rows of the array include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. The two memory cells of a memory cell pair share a common intra-pair bitline. Adjacent memory cell pairs share a common inter-pair bitline. To perform a data read operation on a particular memory cell in a memory cell pair in the rows and columns of the array, wordline drive circuitry transmits wordline activate signals to select both the row for the data read operation and a particular one of the pair of memory cells for the data read operation.
    Type: Application
    Filed: December 10, 2013
    Publication date: April 10, 2014
    Applicant: International Business Machines Corporation
    Inventors: Michael Ju Hyeok Lee, Bao G Truong
  • Publication number: 20140098597
    Abstract: A memory includes an array of memory cells that form rows and columns. The rows include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. For a read operation, a wordline drive circuit selects one memory cell of the pair, the selected memory cell being an addressed memory cell while the remaining cell is an unaddressed memory cell. In response to a wordline enable signal, a pass gate in the addressed memory cell couples the addressed memory cell via a complement bitline to an evaluation gate that resolves the data from the read operation. During the read operation, the unaddressed memory cell couples via another pass gate to a true bitline that terminates without an evaluation gate to conserve energy.
    Type: Application
    Filed: December 11, 2013
    Publication date: April 10, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Michael Ju Hyeok Lee, Bao G. Truong
  • Publication number: 20130141997
    Abstract: A memory includes an array of memory cells that form rows and columns. The rows include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. For a read operation, a wordline drive circuit selects one memory cell of the pair, the selected memory cell being an addressed memory cell while the remaining cell is an unaddressed memory cell. In response to a wordline enable signal, a pass gate in the addressed memory cell couples the addressed memory cell via a complement bitline to an evaluation gate that resolves the data from the read operation. During the read operation, the unaddressed memory cell couples via another pass gate to a true bitline that terminates without an evaluation gate to conserve energy.
    Type: Application
    Filed: December 6, 2011
    Publication date: June 6, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Michael Ju Hyeok Lee, Bao G. Truong
  • Publication number: 20130141992
    Abstract: A memory includes an array of memory cells that form rows and columns. The rows of the array include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. The two memory cells of a memory cell pair share a common intra-pair bitline. Adjacent memory cell pairs share a common inter-pair bitline. To perform a data read operation on a particular memory cell in a memory cell pair in the rows and columns of the array, wordline drive circuitry transmits wordline activate signals to select both the row for the data read operation and a particular one of the pair of memory cells for the data read operation.
    Type: Application
    Filed: December 6, 2011
    Publication date: June 6, 2013
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Michael Ju Hyeok Lee, Bao G. Truong
  • Patent number: 8375172
    Abstract: A mechanism is provided for enabling a proper write through during a write-through operation. Responsive to determining the memory access as a write-through operation, first circuitry determines whether a data input signal is in a first state or a second state. Responsive to the data input signal being in the second state, the first circuitry outputs a global write line signal in the first state. Responsive to the global write line signal being in the first state, second circuitry outputs a column select signal in the second state. Responsive to the column select signal being in the second state, third circuitry keeps a downstream read path of the cache access memory at the first state such that data output by the cache memory array is in the first state.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: February 12, 2013
    Assignee: International Business Machines Corporation
    Inventors: Eddie K. Chan, Michael J. Lee, Ricardo H. Nigaglioni, Bao G. Truong
  • Patent number: 8239430
    Abstract: Performing a calculation using a coordinate rotation digital computer (CORDIC) algorithm. Execution of the CORDIC algorithm is begun. An error introduced by a truncated vector as a result of executing the CORDIC algorithm is pre-computed. The error is incorporated into a subsequent iteration of the CORDIC algorithm. Execution of the CORDIC algorithm is completed. The result of the CORDIC algorithm is stored.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: August 7, 2012
    Assignee: International Business Machines Corporation
    Inventors: David N. Ault, Emiliano Lozano, Bao G. Truong, Samuel I. Ward
  • Publication number: 20110258395
    Abstract: A mechanism is provided for enabling a proper write through during a write-through operation. Responsive to determining the memory access as a write-through operation, first circuitry determines whether a data input signal is in a first state or a second state. Responsive to the data input signal being in the second state, the first circuitry outputs a global write line signal in the first state. Responsive to the global write line signal being in the first state, second circuitry outputs a column select signal in the second state. Responsive to the column select signal being in the second state, third circuitry keeps a downstream read path of the cache access memory at the first state such that data output by the cache memory array is in the first state.
    Type: Application
    Filed: April 16, 2010
    Publication date: October 20, 2011
    Applicant: International Business Machines Corporation
    Inventors: Eddie K. Chan, Michael J. Lee, Ricardo H. Nigaglioni, Bao G. Truong
  • Patent number: 8014215
    Abstract: A mechanism is provided for gating a read access of any row in a cache access memory that has been invalidated. An address decoder in the cache access memory sends a memory access to a non-gated wordline driver and a gated wordline driver associated with the memory access. The non-gated wordline driver outputs the data stored in a valid bit memory cell to the gated wordline driver in response to the non-gated wordline driver determining the memory access as a read access. The gated wordline driver determines whether the data from the valid bit memory cell from the non-gated wordline driver indicates either valid data or invalid data in response to the gated wordline driver determining the memory access as a read access and denies an output of the data in a row of memory cells associated with the gated wordline driver in response to the data being invalid.
    Type: Grant
    Filed: December 10, 2009
    Date of Patent: September 6, 2011
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Lee, Bao G. Truong, Samuel I. Ward
  • Patent number: 8006152
    Abstract: A method comprises generating a test pattern for a device under test (DUT), wherein the DUT comprises a plurality of scan chains coupled to a plurality of multiple input shift registers (MISRs). The plurality of faults detected by a first MISR and by a second MISR are identified. In the event the plurality of faults detected by the first MISR does not include any of the plurality of faults detected by the second MISR and the plurality of faults detected by the second MISR does not include any of the plurality of faults detected by the first MISR, the first MISR and the second MISR are coupled as an independent MISR pair. The test pattern is applied to the DUT to generate a scan chain output. The independent MISR pair captures the scan chain output to generate a test signature. The test signature is compared with a known good signature.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: August 23, 2011
    Assignee: International Business Machines Corporation
    Inventors: Samuel I. Ward, Patrick R. Crosby, William D. Ramsour, Bao G. Truong
  • Publication number: 20110141826
    Abstract: A mechanism is provided for gating a read access of any row in a cache access memory that has been invalidated. An address decoder in the cache access memory sends a memory access to a non-gated wordline driver and a gated wordline driver associated with the memory access. The non-gated wordline driver outputs the data stored in a valid bit memory cell to the gated wordline driver in response to the non-gated wordline driver determining the memory access as a read access. The gated wordline driver determines whether the data from the valid bit memory cell from the non-gated wordline driver indicates either valid data or invalid data in response to the gated wordline driver determining the memory access as a read access and denies an output of the data in a row of memory cells associated with the gated wordline driver in response to the data being invalid.
    Type: Application
    Filed: December 10, 2009
    Publication date: June 16, 2011
    Applicant: International Business Machines Corporation
    Inventors: Michael J. Lee, Bao G. Truong, Samuel I. Ward
  • Patent number: 7920978
    Abstract: A circuit for detecting noise events in a system with time variable operating points is provided. A first voltage, which is averaged over time, is compared to a second voltage. A signal is generated to instruct circuits within a processor to initiate actions to keep a voltage from drooping further.
    Type: Grant
    Filed: October 30, 2008
    Date of Patent: April 5, 2011
    Assignee: International Business Machines Corporation
    Inventors: Daniel Douriet, Anand Haridass, Andreas Huber, Colm B. O'Reilly, Bao G. Truong, Roger D. Weekly
  • Patent number: 7904849
    Abstract: A mechanism for reducing the vertical cross-talk interference experienced in signal lines due to the inductive affects from signal lines in other signal planes of a multi-layer ceramic package is provided. With the apparatus and method, one or more vias in the multi-layer ceramic package may be removed from the structure to provide area through which an offset of the signal lines may pass. Because these offsets of the signal lines exist in parallel planes above or below each other, with no ground lines existing directly between these signal line offsets, a capacitive cross-talk is introduced into the signal lines. This capacitive cross-talk is opposite in polarity to the inductive cross-talk already experienced by the signal lines. As a result, the capacitive cross-talk tends to negate or reduce the inductive cross-talk thereby reducing the far end noise in the signal line.
    Type: Grant
    Filed: December 6, 2007
    Date of Patent: March 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Anand Haridass, Andreas Huber, Bao G. Truong, Roger D. Weekly
  • Patent number: 7835453
    Abstract: A driver circuit is configured as a frequency compensated differential amplifier having one input coupled to a first data signal and a second input coupled to a second data signal. Each stage of the differential amplifier is biased with a current source. The driver circuit generates a first output signal coupled to the input of a first transmission line and a second output signal coupled to the input of a second transmission line. The first and second output signals are generated as the difference between the first and second data signals amplified by a compensated gain. A compensation network that attenuates the low frequency components of the input signals relative to the high frequency components is coupled between current sources biasing the differential amplifier. The outputs of the first and second transmission lines are coupled to the inputs of a differential receiver that may or may not be frequency compensated.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: November 16, 2010
    Assignee: International Business Machines Corporation
    Inventors: Anand Haridass, Bao G. Truong, Joel D. Ziegelbein
  • Patent number: 7804728
    Abstract: An information handling system (IHS) includes a processor with on-chip or off-chip SRAM array. After a read operation, a control circuit may instruct the SRAM array to conduct a precharge operation, or alternatively, instruct the SRAM array to conduct an equalize bitline voltage operation. A read operation may follow the precharge operation or the equalize bitline voltage operation. The control circuit may instruct the SRAM array to conduct an equalize bitline voltage operation if an equalized voltage of a bitline pair exhibits more that a predetermined amount of voltage. Otherwise, the control circuit instructs the SRAM array to conduct a precharge operation before the next read operation.
    Type: Grant
    Filed: August 4, 2008
    Date of Patent: September 28, 2010
    Assignee: International Business Machines Corporation
    Inventors: Michael Ju Hyeok Lee, Bao G Truong
  • Patent number: 7788443
    Abstract: A mechanism is provided for transparent multi-hit correction in associative memories. A content associative memory (CAM) device is provided that transparently and independently executes a precise corrective action in the case of a multiple hit being detected. The wordlines of a CAM array are modified to include a valid bit storage circuit element that indicates whether or not the corresponding wordline is valid or not. In operation, if multiple hits are detected, the multiple hit is signaled to the host system and the particular entries in the CAM array corresponding to the multiple hits are invalidated by setting their associated valid bit storage circuit elements to an invalid value or clearing the value in the associated valid bit storage circuit element. Any data returned to the host system as a result of the multiple hits is invalidated in the host system in response to the signaling of the multiple hits.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: August 31, 2010
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Lee, Vinod Ramadurai, Bao G. Truong
  • Patent number: 7788444
    Abstract: Mechanisms for multiple hit (multi-hit) detection in associative memories, such as a content addressable memory (CAM), are provided. The illustrative embodiments include a hit bitline that discharges as RAM side entries of the associative memory are accessed. The hit bitline is precharged high and pulled low by a series of devices that are activated as each RAM side row is accessed. As more RAM side rows are accessed, the hit bitline drops lower in voltage. The hit bitline drives an inverter with a threshold set such that any voltage equal to or lower than the threshold indicates a multi-hit situation. Any voltage higher than the threshold indicates a single hit or “no-hit” situation. Thus, from the voltage of the hit bitline, the presence of a multi-hit condition may be detected.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: August 31, 2010
    Assignee: International Business Machines Corporation
    Inventors: Michael J. Lee, Bao G. Truong
  • Publication number: 20100180168
    Abstract: A method comprises generating a test pattern for a device under test (DUT), wherein the DUT comprises a plurality of scan chains coupled to a plurality of multiple input shift registers (MISRs). The plurality of faults detected by a first MISR and by a second MISR are identified. In the event the plurality of faults detected by the first MISR does not include any of the plurality of faults detected by the second MISR and the plurality of faults detected by the second MISR does not include any of the plurality of faults detected by the first MISR, the first MISR and the second MISR are coupled as an independent MISR pair. The test pattern is applied to the DUT to generate a scan chain output. The independent MISR pair captures the scan chain output to generate a test signature. The test signature is compared with a known good signature.
    Type: Application
    Filed: January 12, 2009
    Publication date: July 15, 2010
    Applicant: International Business Machines Corporation
    Inventors: Samuel I. Ward, Patrick R. Crosby, William D. Ramsour, Bao G. Truong
  • Patent number: 7673204
    Abstract: A method is provided that uses non-linear data compression in order to generate a set of test vectors for use in scan testing an integrated circuit. The method includes the steps of initially designing the set of test vectors, and selecting one of multiple available coding schemes for each test vector wherein at least two of the coding schemes selected for encoding are different from one another, and wherein one of the available coding schemes represents non-encoded data. The method further comprises operating a random pattern generator to generate data blocks, each corresponding to one of the test vectors, wherein the data block corresponding to a given test vector is encoded with a bit pattern representing the coding scheme of the given test vector. The corresponding data block also has a bit length that is less than the bit length of the given test vector.
    Type: Grant
    Filed: July 5, 2007
    Date of Patent: March 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: Gahn W. Krishnakalin, Emiliano Lozano, Bao G. Truong, Samuel I. Ward
  • Publication number: 20100027361
    Abstract: An information handling system (IHS) includes a processor with on-chip or off-chip SRAM array. After a read operation, a control circuit may instruct the SRAM array to conduct a precharge operation, or alternatively, instruct the SRAM array to conduct an equalize bitline voltage operation. A read operation may follow the precharge operation or the equalize bitline voltage operation. The control circuit may instruct the SRAM array to conduct an equalize bitline voltage operation if an equalized voltage of a bitline pair exhibits more that a predetermined amount of voltage. Otherwise, the control circuit instructs the SRAM array to conduct a precharge operation before the next read operation.
    Type: Application
    Filed: August 4, 2008
    Publication date: February 4, 2010
    Applicant: International Business Machines Corporation
    Inventors: Michael Ju Hyeok Lee, Bao G. Truong