Patents by Inventor Weibiao Zhang

Weibiao Zhang 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).

  • Publication number: 20230101044
    Abstract: Various techniques for implementing resistive temperature sensors that rely on the resistors' temperature sensitivity to provide temperature sensing are disclosed. Temperature sensitive resistors may be implemented in a resistor stack in combination with a resistor stack of resistors that are relatively temperature indifferent. Various temperature sensor circuits implementing these temperature sensitive resistors are also disclosed. A temperature sensor circuit may implement the temperature sensitive resistors along with the resistors that are relatively stable with temperature to output a voltage signal that is indicative of the temperature sensed by the circuit. In some instances, the signal from the temperature sensitive resistors is increased through the use of a feedback resistor loop.
    Type: Application
    Filed: September 24, 2021
    Publication date: March 30, 2023
    Inventors: Craig P. Finlinson, Weibiao Zhang, Tao Zeng
  • Patent number: 11215664
    Abstract: An apparatus includes an integrated circuit that includes an in-circuit power switch coupled to a power supply node, a functional circuit coupled between the in-circuit power switch and a ground node, a test circuit, and a test power switch coupled to the test circuit, wherein the test power switch is a replica of the in-circuit power switch. The test circuit is configured to determine characteristics of the test power switch, and to measure a voltage difference across the in-circuit power switch. The test circuit is also configured to use the characteristics of the test power switch and the voltage difference to determine a power consumption of the functional circuit.
    Type: Grant
    Filed: June 19, 2020
    Date of Patent: January 4, 2022
    Assignee: Apple Inc.
    Inventors: Ke Yun, Weibiao Zhang, Bruno W. Garlepp, Gin S. Yee
  • Publication number: 20210396805
    Abstract: An apparatus includes an integrated circuit that includes an in-circuit power switch coupled to a power supply node, a functional circuit coupled between the in-circuit power switch and a ground node, a test circuit, and a test power switch coupled to the test circuit, wherein the test power switch is a replica of the in-circuit power switch. The test circuit is configured to determine characteristics of the test power switch, and to measure a voltage difference across the in-circuit power switch. The test circuit is also configured to use the characteristics of the test power switch and the voltage difference to determine a power consumption of the functional circuit.
    Type: Application
    Filed: June 19, 2020
    Publication date: December 23, 2021
    Inventors: Ke Yun, Weibiao Zhang, Bruno W. Garlepp, Gin S. Yee
  • Patent number: 10566972
    Abstract: A system and method for efficiently receiving analog input signals. In various embodiments, a functional unit includes a switch in its interface logic. The switch receives an analog input signal, and when enabled, conveys the received input signal as an analog output signal. The switch is enabled when the received enable signal is asserted. However, when the power supply voltage is at a logic low level, an output n-type device is disabled while an output p-type device is enabled. A guard p-type device serially connected with the output p-type device is disabled by other devices used to control the guard p-type device. The control devices also ensure that the body terminals of the guard p-type device and other p-type devices receive a logic high level regardless of the power supply value, which prevents forward bias currents in parasitic diodes of the p-type devices.
    Type: Grant
    Filed: April 2, 2019
    Date of Patent: February 18, 2020
    Assignee: Apple Inc.
    Inventor: Weibiao Zhang
  • Patent number: 10088857
    Abstract: A highly granular voltage regulator is disclosed. The voltage regulator circuit includes first and second current mirror circuits coupled to first and second control circuits, respectively. The voltage regulator circuit further includes an amplifier having an inverting input and a non-inverting input. The first current mirror circuit is coupled to the non-inverting input, whereas the second current mirror circuit is coupled to the inverting input. The first control circuit is operable to control a current provided by the first current mirror circuit, while the second control circuit is operable to control a current provided by the second current mirror circuit.
    Type: Grant
    Filed: September 26, 2017
    Date of Patent: October 2, 2018
    Assignee: Apple Inc.
    Inventors: Weibiao Zhang, Daniel J. Fritchman, Jafar Savoj, Venkatesh B Acharya
  • Patent number: 9069405
    Abstract: A method of operating a touch-sensing surface may include determining a presence of at least one conductive object at the touch-sensing surface by performing a search measurement of a first set of sensor elements of the touch-sensing surface, and in response to determining the presence of the at least one conductive object, determining a location of the at least one conductive object by performing a tracking measurement of a second set of sensor elements of the touch-sensing surface.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: June 30, 2015
    Assignee: CYPRESS SEMICONDUCTOR CORPORATION
    Inventors: Edward Grivna, Jason Baumbach, David Bordui, Weibiao Zhang, MingChan Chen, Tao Peng
  • Patent number: 9007342
    Abstract: A method of operating a touch-sensing surface may include performing a first scan of a first set of electrodes of a touch-sensing surface, determining a presence of at least one conductive object proximate to the touch-sensing surface, in response to determining the presence of the at least one conductive object, performing a second scan of a second set of electrodes of the touch-sensing surface, and repeating the performing the second scan until the at least one conductive object is no longer proximate to the touch-sensing surface.
    Type: Grant
    Filed: July 25, 2013
    Date of Patent: April 14, 2015
    Assignee: Cypress Semiconductor Corporation
    Inventors: Edward Grivna, Jason Baumbach, David Bordui, Weibiao Zhang, MingChan Chen, Tao Peng
  • Patent number: 8760829
    Abstract: An apparatus comprises a first PFET including a first intrinsic body diode; an electrostatic discharge (ESD) subcircuit coupled to a source of the first PFET; a reverse bias voltage element, such as a zener diode, an anode of which is coupled to a gate of the first PFET; a second PFET having a source coupled to a cathode of the zener diode a capacitor coupled to a gate the second PFET; and a first resistor coupled to the gate of the second PFET. The apparatus can protect against both positive and negative electro static transient discharge events.
    Type: Grant
    Filed: April 2, 2012
    Date of Patent: June 24, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Liang Wang, Weibiao Zhang, Dening Wang, John Eric Kunz, Jr.
  • Publication number: 20130307823
    Abstract: A method of operating a touch-sensing surface may include performing a first scan of a first set of electrodes of a touch-sensing surface, determining a presence of at least one conductive object proximate to the touch-sensing surface, in response to determining the presence of the at least one conductive object, performing a second scan of a second set of electrodes of the touch-sensing surface, and repeating the performing the second scan until the at least one conductive object is no longer proximate to the touch-sensing surface.
    Type: Application
    Filed: July 25, 2013
    Publication date: November 21, 2013
    Applicant: CYPRESS SEMICONDUCTOR CORPORATION
    Inventors: Edward Grivna, Jason Baumbach, David Bordui, Weibiao Zhang, MingChan Chen, Tao Peng
  • Patent number: 8547064
    Abstract: A battery cell tab monitoring apparatus includes a conductive element electrically connected between two battery cells. The conductive element is connected to a sensing circuit including a pull-down current source connected to pull current from the conductive element and/or a pull-up current source connected to drive current into the conductive element. A voltage measuring circuit is connected to sense voltages during operation of the pull-down current source and the pull-up current source to be used to determine the status of the conductive element. For instance, voltages beyond certain fixed or variable thresholds indicate that the conductive element is flexing or cracking, which can be a precursor to its breaking. Voltages beyond other fixed or variable thresholds indicate that the conductive element is fully disconnected. The current sources used to push and pull the sensing currents may be used to bring the battery cells into balance when an imbalance is detected.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: October 1, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: J. Randall Cooper, Weibiao Zhang, Kyl W. Scott
  • Patent number: 8541981
    Abstract: A control circuit of a battery power-path management circuit establishes a first power path between a battery input node and an output node when the input node voltage is larger than a charger input node voltage and a second power path between the charger input node and the output node when the voltage on the charger input node is larger than the battery input node voltage. It controls the second power path to provide power to the output node, enabling battery charging and protection over a battery voltage range from about zero volts. It has low power consumption and can support wide-swing power supply voltage from as low as one volt to as high as maximum allowed Vds of drain-extended devices. It can use smaller device sizes because the PMOS switch gate voltage is 0V when the power supply is not too high.
    Type: Grant
    Filed: November 10, 2010
    Date of Patent: September 24, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Weibiao Zhang, J. Randall Cooper
  • Publication number: 20130188286
    Abstract: An apparatus comprises a first PFET including a first intrinsic body diode; an electrostatic discharge (ESD) subcircuit coupled to a source of the first PFET; a reverse bias voltage element, such as a zener diode, an anode of which is coupled to a gate of the first PFET; a second PFET having a source coupled to a cathode of the zener diode a capacitor coupled to a gate the second PFET; and a first resistor coupled to the gate of the second PFET. The apparatus can protect against both positive and negative electro static transient discharge events.
    Type: Application
    Filed: April 2, 2012
    Publication date: July 25, 2013
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Liang Wang, Weibiao Zhang, Dening Wang, John Eric Kunz, JR.
  • Publication number: 20120112686
    Abstract: A control circuit of a battery power-path management circuit establishes a first power path between a battery input node and an output node when the input node voltage is larger than a charger input node voltage and a second power path between the charger input node and the output node when the voltage on the charger input node is larger than the battery input node voltage. It controls the second power path to provide power to the output node, enabling battery charging and protection over a battery voltage range from about zero volts. It has low power consumption and can support wide-swing power supply voltage from as low as one volt to as high as maximum allowed Vds of drain-extended devices. It can use smaller device sizes because the PMOS switch gate voltage is 0V when the power supply is not too high.
    Type: Application
    Filed: November 10, 2010
    Publication date: May 10, 2012
    Applicant: Texas Instruments Incorporated
    Inventors: Weibiao Zhang, J. Randall Cooper
  • Patent number: 8120884
    Abstract: A voltage protection circuit that has a protection transistor coupled between a voltage supply pin of an integrated circuit and a voltage output terminal of the integrated circuit. A biasing circuit is coupled to a control node of the protection transistor and configured to cause the protection transistor to turn on to form a low impedance path between the voltage supply pin and the voltage output terminal when a positive supply voltage is coupled to the voltage supply terminal and to cause the protection transistor to turn off when a negative supply voltage is coupled to the voltage supply terminal. An electro-static discharge (ESD) protection circuit may also be connected between the voltage supply pin and a reference node that is configured to conduct a negative static discharge current for period of time, and to not conduct a negative current continuously.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: February 21, 2012
    Assignee: Texas Instruments Incorporated
    Inventor: Weibiao Zhang
  • Publication number: 20110195744
    Abstract: A voltage protection circuit that has a protection transistor coupled between a voltage supply pin of an integrated circuit and a voltage output terminal of the integrated circuit. A biasing circuit is coupled to a control node of the protection transistor and configured to cause the protection transistor to turn on to form a low impedance path between the voltage supply pin and the voltage output terminal when a positive supply voltage is coupled to the voltage supply terminal and to cause the protection transistor to turn off when a negative supply voltage is coupled to the voltage supply terminal. An electro-static discharge (ESD) protection circuit may also be connected between the voltage supply pin and a reference node that is configured to conduct a negative static discharge current for period of time, and to not conduct a negative current continuously.
    Type: Application
    Filed: February 9, 2010
    Publication date: August 11, 2011
    Inventor: Weibiao Zhang
  • Publication number: 20110140673
    Abstract: A battery management system for charging a battery by a charger includes a transistor and either a charge pump or a push-pull output driver. The transistor increases and decreases an electrical connection between the battery and a voltage from the charger and transmits a charge current from the charger to the battery by turning on and off in response to a pulse width modulated drive signal generated by the charge pump or the push-pull output driver. The charge pump or the push-pull output driver increases the drive signal when the voltage from the charger is above a pre-charge threshold voltage and decreases the drive signal when the voltage from the charger is below the pre-charge threshold voltage.
    Type: Application
    Filed: December 10, 2009
    Publication date: June 16, 2011
    Applicant: Texas Insturments Incorporated
    Inventors: Weibiao Zhang, Mark A. Hamlett, J. Randall Cooper
  • Publication number: 20110025629
    Abstract: A method of operating a touch-sensing surface may include determining a presence of at least one conductive object at the touch-sensing surface by performing a search measurement of a first set of sensor elements of the touch-sensing surface, and in response to determining the presence of the at least one conductive object, determining a location of the at least one conductive object by performing a tracking measurement of a second set of sensor elements of the touch-sensing surface.
    Type: Application
    Filed: July 27, 2010
    Publication date: February 3, 2011
    Applicant: CYPRESS SEMICONDUCTOR CORPORATION
    Inventors: Edward Grivna, Jason Baumbach, David Bordui, Weibiao Zhang, MingChan Chen, Tao Peng
  • Patent number: 6992608
    Abstract: A latch architecture for driving unit current cell of a current-steering digital-to-analog converter (DAC) which reduces the drain-source voltage variation of the output current-source transistors and reduces the coupling of unwanted injection of input digital signals as well as clock signals is presented herein. Moreover, this latch helps to achieve lower glitch during code transition with improved dynamic performance. The latch effectively uses the intrinsic RC delay of most transistors within the latch architecture in order to achieve optimal crossing points of complementary control signals. Unwanted input injection or cross-talk is reduced by introducing transistors (904, 906, 932 and 934) that are off during code transitions without compromising the DAC update speed. Conflicts between currently held and new inputs are avoided in an effort to reduce the harmonic distortion.
    Type: Grant
    Filed: April 13, 2004
    Date of Patent: January 31, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Weibiao Zhang, Bertan Bakkaloglu
  • Patent number: 6985045
    Abstract: A gain controlled voltage controlled oscillator. A current controlled oscillator is adapted to provide an output signal oscillating at a frequency controllable by controlling a current applied thereto. A first current source provides a first control current controllable by controlling a voltage applied thereto that has a predetermined range. A first current mirror is adapted to mirror the control current to the current controlled oscillator. A second current source is adapted to provide a second control current for mirroring to the current controlled oscillator by the first current mirror when the control voltage is in a low portion of the range.
    Type: Grant
    Filed: March 2, 2004
    Date of Patent: January 10, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Weibiao Zhang, Patrick P. Siniscalchi
  • Patent number: 6975255
    Abstract: A dithering method is provided for sigma-delta converters in a deep-submicron process. The dither is a random interleaving of quantizer thresholds levels. The random interleaving dither is more effective than previous static dither methods to remove idle channel tones of sigma-delta analog-to-digital converters (ADC). The dither is easy to implement and takes less area than other dynamic dither methods.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: December 13, 2005
    Assignee: Texas Instruments Incorporated
    Inventor: Weibiao Zhang