Patents by Inventor Sri Navaneethakrishnan Easwaran

Sri Navaneethakrishnan Easwaran 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: 11581723
    Abstract: An integrated circuit includes an output terminal, an analog output circuit, a digital output circuit, and a protection circuit. The analog output circuit includes an output coupled to the output terminal. The digital output circuit includes an output. The protection circuit includes a protection transistor and a comparator circuit. The protection transistor includes a first terminal coupled to the output of the digital output circuit, a second terminal coupled to the output terminal, and a control terminal. The comparator circuit includes a first input coupled to the output terminal, a second input coupled to a reference current source, and an output coupled to the control terminal of the protection transistor.
    Type: Grant
    Filed: November 23, 2020
    Date of Patent: February 14, 2023
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sri Navaneethakrishnan Easwaran, Zhipeng Ye, Deepak Sreedharan
  • Patent number: 11469788
    Abstract: Multiple sensors are coupled to a first pin of a PSI5 transceiver to receive a sensor bus signal. A Manchester decoder is coupled to a second pin and a battery is coupled to a third pin. A comparator receives a first voltage that is proportional to a current on the sensor bus signal and a second voltage that is proportional to a base current on the sensor bus signal and sends a data output signal to the second pin. A sample-and-hold circuit captures a third voltage used to effect the second voltage responsive to a high value on a base current sampling signal. A base-current-renewal circuit detects edge transitions on the data output signal and when the data output signal has no edge transitions for a period of time greater than a gap time defined in a PSI5 standard, sets the base current sampling signal high.
    Type: Grant
    Filed: August 12, 2020
    Date of Patent: October 11, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sri Navaneethakrishnan Easwaran, Ted F. Lekan, Michael J. Zroka, Darren J. Rollman
  • Patent number: 11368009
    Abstract: An electronic control unit (ECU) operates between first and second voltage rails and includes an amplifier circuit and a single current sense circuit coupled to carry a signal to a bus pin and to protect the bus pin from both a short to ground and a short to battery. The single current sense circuit includes a switch circuit that passes the signal to the bus pin and a forward current sensing circuit that provides a second current that is proportional to an output current at the bus pin. The forward current sensing circuit causes the second current to be substantially zero when voltage on the bus pin is above a given value. The single current sense circuit also includes a forward current protection circuit and a reverse current switching circuit that receives the second current and closes a connection to the second voltage when the second current is zero.
    Type: Grant
    Filed: September 14, 2020
    Date of Patent: June 21, 2022
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sri Navaneethakrishnan Easwaran, Timothy Paul Duryea
  • Publication number: 20210408778
    Abstract: An integrated circuit includes an output terminal, an analog output circuit, a digital output circuit, and a protection circuit. The analog output circuit includes an output coupled to the output terminal. The digital output circuit includes an output. The protection circuit includes a protection transistor and a comparator circuit. The protection transistor includes a first terminal coupled to the output of the digital output circuit, a second terminal coupled to the output terminal, and a control terminal. The comparator circuit includes a first input coupled to the output terminal, a second input coupled to a reference current source, and an output coupled to the control terminal of the protection transistor.
    Type: Application
    Filed: November 23, 2020
    Publication date: December 30, 2021
    Inventors: Sri Navaneethakrishnan EASWARAN, Zhipeng YE, Deepak SREEDHARAN
  • Patent number: 10884037
    Abstract: An angular resolver system includes, for example, an imbalance detector for detecting degraded resolver output signals. The imbalance detector includes a first and second power averaging circuits and a comparator circuit. The first power averaging circuit includes a first integrator for generating over a first time window a first average power signal in response to resolver sensor output signals. The second power averaging circuit includes a second integrator for generating over a second time window a second average power signal in response to the resolver sensor output signals, where the first time window is longer than the second time window. The comparator circuit compares the first average power signal and the second average power signal and generates a fault signal when the first average power signal and the second average power signal differ by a selected voltage threshold.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: January 5, 2021
    Assignee: Texas Instruments Incorporated
    Inventors: Shanmuganand Chellamuthu, Qunying Li, Sri Navaneethakrishnan Easwaran
  • Publication number: 20200373960
    Abstract: Multiple sensors are coupled to a first pin of a PSI5 transceiver to receive a sensor bus signal. A Manchester decoder is coupled to a second pin and a battery is coupled to a third pin. A comparator receives a first voltage that is proportional to a current on the sensor bus signal and a second voltage that is proportional to a base current on the sensor bus signal and sends a data output signal to the second pin. A sample-and-hold circuit captures a third voltage used to effect the second voltage responsive to a high value on a base current sampling signal. A base-current-renewal circuit detects edge transitions on the data output signal and when the data output signal has no edge transitions for a period of time greater than a gap time defined in a PSI5 standard, sets the base current sampling signal high.
    Type: Application
    Filed: August 12, 2020
    Publication date: November 26, 2020
    Inventors: Sri Navaneethakrishnan Easwaran, Ted F. Lekan, Michael J. Zroka, Darren J. Rollman
  • Patent number: 10804691
    Abstract: An electronic control unit (ECU) operates between first and second voltage rails and includes an amplifier circuit and a single current sense circuit coupled to carry a signal to a bus pin and to protect the bus pin from both a short to ground and a short to battery. The single current sense circuit includes a switch circuit that passes the signal to the bus pin and a forward current sensing circuit that provides a second current that is proportional to an output current at the bus pin. The forward current sensing circuit causes the second current to be substantially zero when voltage on the bus pin is above a given value. The single current sense circuit also includes a forward current protection circuit and a reverse current switching circuit that receives the second current and closes a connection to the second voltage when the second current is zero.
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: October 13, 2020
    Assignee: Texas Instruments Incorporated
    Inventors: Sri Navaneethakrishnan Easwaran, Timothy Paul Duryea
  • Patent number: 10784917
    Abstract: Multiple sensors are coupled to a first pin of a PSI5 transceiver to receive a sensor bus signal. A Manchester decoder is coupled to a second pin and a battery is coupled to a third pin. A comparator receives a first voltage that is proportional to a current on the sensor bus signal and a second voltage that is proportional to a base current on the sensor bus signal and sends a data output signal to the second pin. A sample-and-hold circuit captures a third voltage used to effect the second voltage responsive to a high value on a base current sampling signal. A base-current-renewal circuit detects edge transitions on the data output signal and when the data output signal has no edge transitions for a period of time greater than a gap time defined in a PSI5 standard, sets the base current sampling signal high.
    Type: Grant
    Filed: July 24, 2019
    Date of Patent: September 22, 2020
    Assignee: Texas Instruments Incorporated
    Inventors: Sri Navaneethakrishnan Easwaran, Ted F. Lekan, Michael J. Zroka, Darren J. Rollman
  • Publication number: 20200169284
    Abstract: Multiple sensors are coupled to a first pin of a PSI5 transceiver to receive a sensor bus signal. A Manchester decoder is coupled to a second pin and a battery is coupled to a third pin. A comparator receives a first voltage that is proportional to a current on the sensor bus signal and a second voltage that is proportional to a base current on the sensor bus signal and sends a data output signal to the second pin. A sample-and-hold circuit captures a third voltage used to effect the second voltage responsive to a high value on a base current sampling signal. A base-current-renewal circuit detects edge transitions on the data output signal and when the data output signal has no edge transitions for a period of time greater than a gap time defined in a PSI5 standard, sets the base current sampling signal high.
    Type: Application
    Filed: July 24, 2019
    Publication date: May 28, 2020
    Inventors: Sri Navaneethakrishnan Easwaran, Ted F. Lekan, Michael J. Zroka, Darren J. Rollman
  • Patent number: 10578666
    Abstract: A circuit comprises a CLVS, a LEA coupled to the CLVS, and a peak detector coupled to the CLVS and the LEA, wherein the peak detector is a switch-based peak detector. A method comprises closing a first switch for a period of time to provide a current to an actuator, opening the first switch after the period, measuring, after the opening, a voltage associated with the actuator, and determining, based on the measuring and using an ADC, whether a diode is present in the actuator and coupled with a correct polarity, is missing, or is present in the actuator and coupled with an incorrect polarity.
    Type: Grant
    Filed: July 18, 2016
    Date of Patent: March 3, 2020
    Assignee: Texas Instruments Incorporated
    Inventors: Sri Navaneethakrishnan Easwaran, Sunil Kashyap Venugopal
  • Patent number: 10520971
    Abstract: A current sink circuit coupled to pull down a gate control node (GCN) for an NMOS power FET that controls an actuator includes first and second NMOS transistors coupled in series between the GCN and a lower rail, where the first NMOS transistor has a gate and drain coupled together through a resistor. The current sink circuit also includes a control signal generation circuit (CSGC) and a negative voltage blocking circuit (NVBC). The CSGC is coupled to receive at least one voltage input and an ignition signal and to provide a first control signal and a second control signal. The NVBC is coupled to pass the first control signal from the control signal generation circuit to the gate of the first NMOS transistor and to block a negative voltage on the GCN from reaching the CSGC. The second control signal is coupled to the gate of the second NMOS transistor.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: December 31, 2019
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sri Navaneethakrishnan Easwaran, Vijayalakshmi Devarajan, Timothy Paul Duryea, Shanmuganand Chellamuthu
  • Publication number: 20190280472
    Abstract: An electronic control unit (ECU) operates between first and second voltage rails and includes an amplifier circuit and a single current sense circuit coupled to carry a signal to a bus pin and to protect the bus pin from both a short to ground and a short to battery. The single current sense circuit includes a switch circuit that passes the signal to the bus pin and a forward current sensing circuit that provides a second current that is proportional to an output current at the bus pin. The forward current sensing circuit causes the second current to be substantially zero when voltage on the bus pin is above a given value. The single current sense circuit also includes a forward current protection circuit and a reverse current switching circuit that receives the second current and closes a connection to the second voltage when the second current is zero.
    Type: Application
    Filed: March 6, 2018
    Publication date: September 12, 2019
    Inventors: Sri Navaneethakrishnan Easwaran, Timothy Paul Duryea
  • Publication number: 20190025866
    Abstract: A current sink circuit coupled to pull down a gate control node (GCN) for an NMOS power FET that controls an actuator includes first and second NMOS transistors coupled in series between the GCN and a lower rail, where the first NMOS transistor has a gate and drain coupled together through a resistor. The current sink circuit also includes a control signal generation circuit (CSGC) and a negative voltage blocking circuit (NVBC). The CSGC is coupled to receive at least one voltage input and an ignition signal and to provide a first control signal and a second control signal. The NVBC is coupled to pass the first control signal from the control signal generation circuit to the gate of the first NMOS transistor and to block a negative voltage on the GCN from reaching the CSGC. The second control signal is coupled to the gate of the second NMOS transistor.
    Type: Application
    Filed: December 5, 2017
    Publication date: January 24, 2019
    Inventors: Sri Navaneethakrishnan Easwaran, Vijayalakshmi Devarajan, Timothy Paul Duryea, Shanmuganand Chellamuthu
  • Publication number: 20180073895
    Abstract: An angular resolver system includes, for example, an imbalance detector for detecting degraded resolver output signals. The imbalance detector includes a first and second power averaging circuits and a comparator circuit. The first power averaging circuit includes a first integrator for generating over a first time window a first average power signal in response to resolver sensor output signals. The second power averaging circuit includes a second integrator for generating over a second time window a second average power signal in response to the resolver sensor output signals, where the first time window is longer than the second time window. The comparator circuit compares the first average power signal and the second average power signal and generates a fault signal when the first average power signal and the second average power signal differ by a selected voltage threshold.
    Type: Application
    Filed: September 12, 2016
    Publication date: March 15, 2018
    Inventors: Shanmuganand Chellamuthu, Qunying Li, Sri Navaneethakrishnan Easwaran
  • Patent number: 9893757
    Abstract: One example includes an amplifier system. The amplifier system includes an input stage configured to receive an input pulse signal and to generate a reference voltage pulse based on the input pulse signal. The amplifier system also includes an amplifier stage that receives at least one power voltage and is configured to amplify the reference voltage pulse and to provide pulse-shaping of the amplified reference voltage pulse based on a change of amplitude of the at least one power voltage resulting from an amplitude of the reference voltage pulse.
    Type: Grant
    Filed: July 15, 2016
    Date of Patent: February 13, 2018
    Assignee: Texas Instruments Incorporated
    Inventor: Sri Navaneethakrishnan Easwaran
  • Publication number: 20180017601
    Abstract: A circuit comprises a CLVS, a LEA coupled to the CLVS, and a peak detector coupled to the CLVS and the LEA, wherein the peak detector is a switch-based peak detector. A method comprises closing a first switch for a period of time to provide a current to an actuator, opening the first switch after the period, measuring, after the opening, a voltage associated with the actuator, and determining, based on the measuring and using an ADC, whether a diode is present in the actuator and coupled with a correct polarity, is missing, or is present in the actuator and coupled with an incorrect polarity.
    Type: Application
    Filed: July 18, 2016
    Publication date: January 18, 2018
    Inventors: Sri Navaneethakrishnan EASWARAN, Sunil Kashyap VENUGOPAL
  • Publication number: 20170237461
    Abstract: One example includes an amplifier system. The amplifier system includes an input stage configured to receive an input pulse signal and to generate a reference voltage pulse based on the input pulse signal. The amplifier system also includes an amplifier stage that receives at least one power voltage and is configured to amplify the reference voltage pulse and to provide pulse-shaping of the amplified reference voltage pulse based on a change of amplitude of the at least one power voltage resulting from an amplitude of the reference voltage pulse.
    Type: Application
    Filed: July 15, 2016
    Publication date: August 17, 2017
    Inventor: Sri Navaneethakrishnan Easwaran
  • Patent number: 9710002
    Abstract: Dynamic biasing circuits for low drop out (LDO) regulators are described. In some embodiments, an electronic circuit may include a low drop out (LDO) regulator; and a biasing circuit coupled to the LDO regulator, the biasing circuit configured to: monitor a first electrical current and a second electrical current; select a greater of the first or second electrical currents; and provide the selected electrical current to the LDO regulator. In other embodiments, a method may include: providing a digital core and a low drop out (LDO) regulator coupled to the digital core, wherein the digital core is configured to operate in an active mode and in a standby mode; monitoring, via a current selector circuit coupled to the LDO regulator, a first current and a second current; selecting a greater of the first or second electrical currents; and providing the selected current as a biasing current to the LDO regulator.
    Type: Grant
    Filed: November 3, 2015
    Date of Patent: July 18, 2017
    Assignee: Texas Instruments Incorporated
    Inventors: Sri Navaneethakrishnan Easwaran, Vijayalakshmi Devarajan
  • Publication number: 20160349774
    Abstract: Dynamic biasing circuits for low drop out (LDO) regulators are described. In some embodiments, an electronic circuit may include a low drop out (LDO) regulator; and a biasing circuit coupled to the LDO regulator, the biasing circuit configured to: monitor a first electrical current and a second electrical current; select a greater of the first or second electrical currents; and provide the selected electrical current to the LDO regulator. In other embodiments, a method may include: providing a digital core and a low drop out (LDO) regulator coupled to the digital core, wherein the digital core is configured to operate in an active mode and in a standby mode; monitoring, via a current selector circuit coupled to the LDO regulator, a first current and a second current; selecting a greater of the first or second electrical currents; and providing the selected current as a biasing current to the LDO regulator.
    Type: Application
    Filed: November 3, 2015
    Publication date: December 1, 2016
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sri Navaneethakrishnan Easwaran, Vijayalakshmi Devarajan
  • Patent number: 9343898
    Abstract: Apparatus and methods disclosed herein implement steady-state and fast transient electronic current limiting through power transistors, including power transistors used as pass elements associated with general purpose drivers. Embodiments herein prevent excessive steady-state current flow through one or more driver pass elements and/or through load elements in series with the pass element(s) via a current sensing and driver preamplifier feedback loop. A transient over-current protection circuit includes a fast transient switch and a transient over-current control circuit. The transient over-current control circuit rectifies one or more transient voltage spikes to create a momentary direct current (DC) voltage power supply (MVS) to power a fast transient driver circuit and to trip the fast transient switch. The fast transient switch discharges a transient pass element input voltage (e.g.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: May 17, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Sri Navaneethakrishnan Easwaran