Patents by Inventor Xiaowei Deng

Xiaowei Deng 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: 11495301
    Abstract: In one example a semiconductor device has a data latch that includes first and second transmission gates and first and second inverters. The first inverter is connected between a first terminal of the first transmission gate and a first terminal of the second transmission gate. The second inverter is connected between a second terminal of the first transmission gate and a second terminal of the second transmission gate. The data latch is configured to store a datum received at the connection between the first transmission gate and the second inverter, and to store a datum received at the connection between the second transmission gate and the first inverter.
    Type: Grant
    Filed: March 31, 2021
    Date of Patent: November 8, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Yunchen Qiu, David Joseph Toops
  • Patent number: 11355182
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: June 7, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Publication number: 20210304824
    Abstract: In one example a semiconductor device has a data latch that includes first and second transmission gates and first and second inverters. The first inverter is connected between a first terminal of the first transmission gate and a first terminal of the second transmission gate. The second inverter is connected between a second terminal of the first transmission gate and a second terminal of the second transmission gate. The data latch is configured to store a datum received at the connection between the first transmission gate and the second inverter, and to store a datum received at the connection between the second transmission gate and the first inverter.
    Type: Application
    Filed: March 31, 2021
    Publication date: September 30, 2021
    Inventors: Xiaowei Deng, Yunchen Qiu, David Joseph Toops
  • Publication number: 20180068713
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Application
    Filed: October 31, 2017
    Publication date: March 8, 2018
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9805788
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Grant
    Filed: July 31, 2015
    Date of Patent: October 31, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9576643
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Grant
    Filed: July 31, 2015
    Date of Patent: February 21, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9472268
    Abstract: An SRAM with buffered-read bit cells is disclosed (FIGS. 1-6). The integrated circuit includes a plurality of memory cells (102). Each memory cell has a plurality of transistors (200,202). A first memory cell (FIG. 2) is arranged to store a data signal in response to an active write word line (WWL) and to produce the data signal in response to an active read word line (RWL). A test circuit (104) formed on the integrated circuit is operable to test current and voltage characteristics of each transistor of the plurality of transistors of the first memory cell (FIGS. 7-10).
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: October 18, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9466356
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Grant
    Filed: July 31, 2015
    Date of Patent: October 11, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9455021
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: September 27, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9412437
    Abstract: An SRAM with buffered-read bit cells is disclosed (FIGS. 1-6). The integrated circuit includes a plurality of memory cells (102). Each memory cell has a plurality of transistors (200, 202). A first memory cell (FIG. 2) is arranged to store a data signal in response to an active write word line (WWL) and to produce the data signal in response to an active read word line (RWL). A test circuit (104) formed on the integrated circuit is operable to test current and voltage characteristics of each transistor of the plurality of transistors of the first memory cell (FIGS. 7-10).
    Type: Grant
    Filed: January 9, 2014
    Date of Patent: August 9, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 9208832
    Abstract: A method of testing large-scale integrated circuits including multiple instances of memory arrays, and an integrated circuit structure for assisting such testing. In one embodiment, voltage drops due to parasitic resistance in array bias conductors are determined by extracting layout parameters, and subsequent circuit simulation that derives the voltage drops in those conductors during operation of each memory array. In another embodiment, sense lines from each memory array are selectively connected to a test sense terminal of the integrated circuit, at which the array bias voltage at each memory array is externally measured. Feedback control of the applied voltage to arrive at the desired array bias voltage can be performed.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: December 8, 2015
    Assignee: TEXAS INSTURMENTS INCORPORATED
    Inventors: Xiaowei Deng, Yang Yi, Wah Kit Loh
  • Patent number: 9208902
    Abstract: An integrated circuit containing a memory and a sense amplifier. The integrated circuit also containing an extended delay circuit which extends the delay between when a precharged bitline is floated and when a wordline is enabled. A method of testing an integrated circuit to identify bitlines with excessive leakage.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: December 8, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Beena Pious, Xiaowei Deng, Wah Kit Loh, Jon Lescrenier
  • Patent number: 9208899
    Abstract: An integrated circuit on-chip parametric (OCP) test structure includes a static random access memory (SRAM) universal test structure (UTS) having UTS ports and an OCP controller configured to determine first and second UTS ports of the SRAM UTS for independent connection to first and second on-chip test pads, respectively. The integrated circuit OCP test structure further includes a UTS OCP router connected to the OCP controller and configured to connect the first and second UTS ports of the SRAM UTS to the first and second on-chip test pads, respectively. Methods of operating an integrated circuit OCP test structure and OCP testing of an integrated circuit are also included.
    Type: Grant
    Filed: May 5, 2010
    Date of Patent: December 8, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Xiaowei Deng, Wah K. Loh
  • Publication number: 20150348615
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Application
    Filed: July 31, 2015
    Publication date: December 3, 2015
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Publication number: 20150340084
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Application
    Filed: July 31, 2015
    Publication date: November 26, 2015
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Publication number: 20150340081
    Abstract: A method of screening complementary metal-oxide-semiconductor CMOS integrated circuits, such as integrated circuits including CMOS static random access memory (SRAM) cells, for transistors susceptible to transistor characteristic shifts over operating time. For the example of SRAM cells formed of cross-coupled CMOS inverters, separate ground voltage levels can be applied to the source nodes of the driver transistors, or separate power supply voltage levels can be applied to the source nodes of the load transistors (or both). Asymmetric bias voltages applied to the transistors in this manner will reduce the transistor drive current, and can thus mimic the effects of bias temperature instability (BTI). Cells that are vulnerable to threshold voltage shift over time can thus be identified.
    Type: Application
    Filed: July 31, 2015
    Publication date: November 26, 2015
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 8760927
    Abstract: A complementary metal-oxide-semiconductor (CMOS) static random access memory (SRAM) with no well contacts within the memory array. Modern sub-micron CMOS structures have been observed to have reduced vulnerability to latchup. Chip area is reduced by providing no well contacts within the array. Wells of either or both conductivity types may electrically float during operation of the memory. In other implementations, extensions of the array wells into peripheral circuitry may be provided, with well contacts provided in those extended portions.
    Type: Grant
    Filed: July 25, 2012
    Date of Patent: June 24, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Xiaowei Deng
  • Publication number: 20140126277
    Abstract: An SRAM with buffered-read bit cells is disclosed (FIGS. 1-6). The integrated circuit includes a plurality of memory cells (102). Each memory cell has a plurality of transistors (200, 202). A first memory cell (FIG. 2) is arranged to store a data signal in response to an active write word line (WWL) and to produce the data signal in response to an active read word line (RWL). A test circuit (104) formed on the integrated circuit is operable to test current and voltage characteristics of each transistor of the plurality of transistors of the first memory cell (FIGS. 7-10).
    Type: Application
    Filed: January 9, 2014
    Publication date: May 8, 2014
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Patent number: 8716808
    Abstract: An integrated circuit including a complementary metal-oxide-semiconductor (CMOS) static random access memory (SRAM) with periodic deep well structures within the memory cell array. The deep well structures are contacted by surface well regions of the same conductivity type (e.g., n-type) in the memory cell array, forming two-dimensional grids of both n-type and p-type semiconductor material in the memory cell array area. Bias conductors may contact the grids to apply the desired well bias voltages, for example in well-tie regions or peripheral circuitry adjacent to the memory cell array.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: May 6, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Xiaowei Deng, Wah Kit Loh
  • Publication number: 20140078819
    Abstract: Balanced electrical performance in a static random access memory (SRAM) cell with an asymmetric context such as a buffer circuit. Each memory cell includes a circuit feature, such as a read buffer, that has larger transistor sizes and features than the other transistors within the cell, and in which the feature asymmetrical influences the smaller cell transistors. For best performance, pairs of cell transistors are to be electrically matched with one another. One or more of the cell transistors nearer to the asymmetric feature are constructed differently, for example with different channel width, channel length, or net channel dopant concentration, to compensate for the proximity effects of the asymmetric feature.
    Type: Application
    Filed: November 19, 2013
    Publication date: March 20, 2014
    Applicant: Texas Instruments Incorporated
    Inventors: Xiaowei Deng, Wah Kit Loh, Anand Seshardi, Zhonghai Shi