Patents by Inventor Srinath Ramaswamy

Srinath Ramaswamy 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: 9742420
    Abstract: An analog to digital converter (ADC) system that includes a first amplifier configured to amplify an analog input signal to produce an amplified direct current (DC) signal, an ADC configured to receive the amplified DC signal and convert the amplified DC signal into a digital DC signal, a digital to analog converter configured to receive the digital DC signal and convert the digital DC signal into an analog DC signal, and a second amplifier configured to receive an analog alternating current (AC) signal comprising the analog DC signal subtracted from the analog input signal and amplify the analog AC signal to produce an amplified AC signal. The ADC is further configured to receive the amplified AC signal and produce a digital AC signal. The second amplifier has a gain greater than a gain of the first amplifier.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: August 22, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sriram Narayanan, Srinath Ramaswamy, Arup Polley, Ajit Sharma
  • Patent number: 9721349
    Abstract: A periphery band is around an excluded region. For automatically counting physical objects within the periphery band and the excluded region, an imaging sensor captures: a first image of the periphery band and the excluded region; and a second image of the periphery band and the excluded region. In response to the first image, a first number is counted of physical objects within the periphery band and the excluded region. Relevant motion is automatically detected within the periphery band, while ignoring motion within the excluded region. In response to the second image, a second number is counted of physical objects within the periphery band and the excluded region. In response to determining that a discrepancy exists between the detected relevant motion and the second number, the discrepancy is handled.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: August 1, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sriram Narayanan, Russell Rosenquist, Srinath Ramaswamy
  • Patent number: 9711715
    Abstract: Read-only (“RO”) data to be permanently imprinted in storage cells of a memory array are written to the memory array. One or more over-stress conditions such as heat, over-voltage, over-current and/or mechanical stress are then applied to the memory array or to individual storage cells within the memory array. The over-stress condition(s) act upon one or more state-determining elements of the storage cells to imprint the RO data. The over-stress condition permanently alters a value of a state-determining property of the state-determining element without incapacitating normal operation of the storage cell. The altered value of the state-determining property biases the cell according to the state of the RO data bit. The bias is detectable in the cell read-out signal. A pre-written ferroelectric random-access memory (“FRAM”) array is baked. Baking traps electric dipoles oriented in a direction corresponding to a state of the pre-written data and forms am RO data imprint.
    Type: Grant
    Filed: June 22, 2016
    Date of Patent: July 18, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Chiraag Juvekar, Joyce Kwong, Clive Bittlestone, Srinath Ramaswamy, Stephen Heinrich-Barna
  • Patent number: 9690517
    Abstract: A system for error correction code (ECC) management of write-once memory (WOM) codes includes, for example, a controller for selecting between one of a WOM (Write-Only Memory) mode and an ECC (error correction code) mode. A codec is arranged to operate in the selected mode. The codec while operating in the ECC mode is arranged to identify a bit position of at least one bit error in response to ECC parity bits of a first received data word. The codec while operating in the WOM mode is arranged to receive a WOM-encoded word from an addressed location in a WOM device, to receive a second received data word to be encoded and written to the addressed location, and to generate WOM-encoded word for writing to the addressed location in the WOM device. The WOM-encoded word for writing to the addressed location is optionally ECC encoded.
    Type: Grant
    Filed: May 22, 2015
    Date of Patent: June 27, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sai Zhang, Yuming Zhu, Clive Bittlestone, Srinath Ramaswamy
  • Publication number: 20170155398
    Abstract: An analog to digital converter (ADC) system that includes a first amplifier configured to amplify an analog input signal to produce an amplified direct current (DC) signal, an ADC configured to receive the amplified DC signal and convert the amplified DC signal into a digital DC signal, a digital to analog converter configured to receive the digital DC signal and convert the digital DC signal into an analog DC signal, and a second amplifier configured to receive an analog alternating current (AC) signal comprising the analog DC signal subtracted from the analog input signal and amplify the analog AC signal to produce an amplified AC signal. The ADC is further configured to receive the amplified AC signal and produce a digital AC signal. The second amplifier has a gain greater than a gain of the first amplifier.
    Type: Application
    Filed: November 30, 2015
    Publication date: June 1, 2017
    Inventors: Sriram NARAYANAN, Srinath RAMASWAMY, Arup POLLEY, Ajit SHARMA
  • Patent number: 9667289
    Abstract: Reduced noise and power with rapid settling time and increased performance in multi-modal analog multiplexed data acquisition systems. An example apparatus arrangement includes a circuit input configured to receive a plurality of analog input signals; an analog to digital converter circuit configured to output a digital representation of an analog voltage; a selection circuit configured to select one of the analog input signals received at the circuit input; a buffer coupled to receive the selected one of the analog input signals; a filter coupled to the buffer and configured to perform a high bandwidth sample operation and a low bandwidth sample operation and having a filter output, responsive to a control signal; and a sampling capacitor coupled to the filter to sample the filter output, and having an output coupled to the analog to digital converter. Methods and additional apparatus arrangements are disclosed.
    Type: Grant
    Filed: March 29, 2016
    Date of Patent: May 30, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Arup Polley, Ajit Sharma, Seung Bae Lee, Sriram Narayanan, Srinath Ramaswamy
  • Publication number: 20170099711
    Abstract: An LED (light-emitting diode) driver for a photoplethysmography system, including a switched-mode operational amplifier for driving a driver transistor with a source-drain path in series with the LED. In a first clock phase in which the LED is disconnected from the driver transistor, the amplifier is coupled in unity gain mode, and a sampling capacitor stores a voltage corresponding to the offset and flicker noise of the amplifier; the gate of the driver transistor is precharged to a reference voltage in this first clock phase. In a second clock phase, the sampled voltage at the capacitor is subtracted from the reference voltage applied to the amplifier input, so that the LED drive is adjusted according to the sampled noise. A signal from the transmitter channel is forwarded to a noise/ripple remover in the receiving channel, to remove transmitter noise from the received signal.
    Type: Application
    Filed: April 18, 2016
    Publication date: April 6, 2017
    Inventors: Arup Polley, Ajit Sharma, Srinath Ramaswamy, Sriram Narayanan
  • Patent number: 9615427
    Abstract: An optical system includes an optical illumination source, an optical receiver, a correlation determination circuit, and an ambient condition control circuit. The optical illumination source is configured to emit a light in the direction of a target object. The optical receiver is configured to receive a combined optical signal that includes an ambient light component combined with an interrogation component. The correlation determination circuit is configured to compare the combined optical signal with an ambient light signal to identify a correlation factor. The ambient condition control circuit is configured to compare the correlation factor to a low correlation threshold value and a high correlation threshold value, and, based on the correlation factor exceeding the low threshold value and being less than the high correlation threshold value, cancel the ambient light component from the combined optical signal to produce an interrogation signal including the interrogation component.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: April 4, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sriram Narayanan, Srinath Ramaswamy, Arup Polley, Ajit Sharma
  • Publication number: 20170059627
    Abstract: Operating a current sensor by conducting a current serially through a first region and a second region of an electrically conductive member. A first magnetic field produced by the current in the first region is sensed using a first magnetic field based current (MFBC) sensor having a first sensitivity. The sensitivity of a second MFBC is reduced. A second magnetic field produced by the current in the second region is sensed using the second MFBC sensor having a reduced sensitivity, in which the reduced sensitivity is lower than the first sensitivity. A magnitude of the current is calculated based on the first magnetic field and the second magnetic field. A dynamic range of the current sensor is extended by calculating a magnitude of the current using the second magnetic field after the first MFBC is saturated.
    Type: Application
    Filed: December 31, 2015
    Publication date: March 2, 2017
    Inventors: Arup Polley, Srinath Ramaswamy, Terry Lee Sculley
  • Publication number: 20170052253
    Abstract: A transducer system with transducer and circuitry for applying a pulse train at a single frequency to excite the transducer. The transducer is operable to receive an echo waveform in response to the pulse train. The system also comprises circuitry for determining a time of flight as between a first reference time associated with the pulse train and a second reference time associated with the echo waveform.
    Type: Application
    Filed: August 1, 2016
    Publication date: February 23, 2017
    Inventors: Yuming Zhu, Srinath Ramaswamy, Domingo Garcia, Sujeet Milind Patole
  • Publication number: 20170011790
    Abstract: Read-only (“RO”) data consisting of a physically unclonable function (“PUF”) pattern is written to a ferroelectric random-access memory (“FRAM”) memory array. The FRAM array is baked to imprint the PUF pattern with a selected average depth of imprint and a corresponding average read reliability. The average depth of imprint and corresponding average read reliability are determined during testing after baking The PUF pattern as read after baking is compared to the PUF pattern as written prior to baking Additional PUF pattern writing and baking cycles may be performed until the average depth of imprint and associated read reliability reach a first selected level. Integrated circuits determined to be over-imprinted by exceeding a second selected level may be rejected. The first and second levels of PUF pattern imprint are selected such as to produce FRAM arrays with a unique fingerprint for each individual FRAM array-containing integrated circuit.
    Type: Application
    Filed: July 8, 2015
    Publication date: January 12, 2017
    Inventors: Chiraag Juvekar, Joyce Kwong, Clive Bittlestone, Srinath Ramaswamy
  • Publication number: 20160380660
    Abstract: Reduced noise and power with rapid settling time and increased performance in multi-modal analog multiplexed data acquisition systems. An example apparatus arrangement includes a circuit input configured to receive a plurality of analog input signals; an analog to digital converter circuit configured to output a digital representation of an analog voltage; a selection circuit configured to select one of the analog input signals received at the circuit input; a buffer coupled to receive the selected one of the analog input signals; a filter coupled to the buffer and configured to perform a high bandwidth sample operation and a low bandwidth sample operation and having a filter output, responsive to a control signal; and a sampling capacitor coupled to the filter to sample the filter output, and having an output coupled to the analog to digital converter. Methods and additional apparatus arrangements are disclosed.
    Type: Application
    Filed: March 29, 2016
    Publication date: December 29, 2016
    Inventors: Arup Polley, Ajit Sharma, Seung Bae Lee, Sriram Narayanan, Srinath Ramaswamy
  • Publication number: 20160365510
    Abstract: Read-only (“RO”) data to be permanently imprinted in storage cells of a memory array are written to the memory array. One or more over-stress conditions such as heat, over-voltage, over-current and/or mechanical stress are then applied to the memory array or to individual storage cells within the memory array. The over-stress condition(s) act upon one or more state-determining elements of the storage cells to imprint the RO data. The over-stress condition permanently alters a value of a state-determining property of the state-determining element without incapacitating normal operation of the storage cell. The altered value of the state-determining property biases the cell according to the state of the RO data bit. The bias is detectable in the cell read-out signal. A pre-written ferroelectric random-access memory (“FRAM”) array is baked. Baking traps electric dipoles oriented in a direction corresponding to a state of the pre-written data and forms am RO data imprint.
    Type: Application
    Filed: June 22, 2016
    Publication date: December 15, 2016
    Inventors: Chiraag Juvekar, Joyce Kwong, Clive Bittlestone, Srinath Ramaswamy, Stephen Heinrich-Barna
  • Publication number: 20160342471
    Abstract: A system for error correction code (ECC) management of write-once memory (WOM) codes includes, for example, a controller for selecting between one of a WOM (Write-Only Memory) mode and an ECC (error correction code) mode. A codec is arranged to operate in the selected mode. The codec while operating in the ECC mode is arranged to identify a bit position of at least one bit error in response to ECC parity bits of a first received data word. The codec while operating in the WOM mode is arranged to receive a WOM-encoded word from an addressed location in a WOM device, to receive a second received data word to be encoded and written to the addressed location, and to generate WOM-encoded word for writing to the addressed location in the WOM device. The WOM-encoded word for writing to the addressed location is optionally ECC encoded.
    Type: Application
    Filed: May 22, 2015
    Publication date: November 24, 2016
    Inventors: Sai Zhang, Yuming Zhu, Clive Bittlestone, Srinath Ramaswamy
  • Publication number: 20160328289
    Abstract: A system for error correction code (ECC) management of write-once memory (WOM) codes includes, for example, a host processor is arranged to send a data word that is to be stored in a WOM (Write-Only Memory) device. A host interface is arranged to receive the first data word for processing by a WOM controller and an ECC controller. The WOM controller is for generating a first WOM-encoded word in response to an original symbol of the first data word, while the ECC controller is for generating a first set of ECC bits in response to the original symbol of the first data word. A memory device interface is for writing the first WOM-encoded word and the first set of ECC bits to the WOM device in accordance with the memory address associated with the first data word.
    Type: Application
    Filed: May 4, 2015
    Publication date: November 10, 2016
    Inventors: Sai Zhang, Yuming Zhu, Clive Bittlestone, Srinath Ramaswamy
  • Publication number: 20160276731
    Abstract: An apparatus is provided. In the apparatus, there is an antenna package and an integrated circuit (IC). A circuit trace assembly is secured to the IC. A coupler (with an antenna assembly and a high impedance surface (HIS)) is secured to the circuit trace assembly. An antenna assembly has a window region, a conductive region that substantially surrounds the window region, a circular patch antenna that is in communication with the IC, and an elliptical patch antenna that is located within the window region, that is extends over at least a portion of the circular patch antenna, and that is in communication with the circular patch antenna. The HIS substantially surrounds the antenna assembly.
    Type: Application
    Filed: May 27, 2016
    Publication date: September 22, 2016
    Inventors: Eunyoung Seok, Srinath Ramaswamy, Brian B. Ginsburg, Vijay B. Rentala, Baher Haroun
  • Patent number: 9432044
    Abstract: A multi-segment capacitive successive approximation analog to digital converter (SAR ADC) is calibrated by determining an error voltage for each of a plurality of most significant bit (MSB) capacitors in a first segment using a calibration DAC. The first segment is connected to the second segment by an attenuation capacitor. Each of the error voltages corresponding to the MSB capacitors is digitized to form a set of digitized error voltages. An error voltage for each of a plurality of less significant bit (LSB) capacitors in at least the second segment is calculated by summing the set of digitized error voltages to form a sum of error voltages (sum(e)) and assigning a percentage of sum(e) as the error voltage for each of the LSB capacitors, such that a mismatch in the attenuation capacitor is mitigated.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: August 30, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Seung Bae Lee, Ajit Sharma, Srinath Ramaswamy
  • Patent number: 9401196
    Abstract: Read-only (“RO”) data to be permanently imprinted in storage cells of a memory array are written to the memory array. One or more over-stress conditions such as heat, over-voltage, over-current and/or mechanical stress are then applied to the memory array or to individual storage cells within the memory array. The over-stress condition(s) act upon one or more state-determining elements of the storage cells to imprint the RO data. The over-stress condition permanently alters a value of a state-determining property of the state-determining element without incapacitating normal operation of the storage cell. The altered value of the state-determining property biases the cell according to the state of the RO data bit. The bias is detectable in the cell read-out signal. A pre-written ferroelectric random-access memory (“FRAM”) array is baked. Baking traps electric dipoles oriented in a direction corresponding to a state of the pre-written data and forms am RO data imprint.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: July 26, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Chiraag Juvekar, Joyce Kwong, Clive Bittlestone, Srinath Ramaswamy, Stephen K. Heinrich-Barna
  • Patent number: 9356352
    Abstract: An apparatus is provided. In the apparatus, there is an antenna package and an integrated circuit (IC). A circuit trace assembly is secured to the IC. A coupler (with an antenna assembly and a high impedance surface (HIS)) is secured to the circuit trace assembly. An antenna assembly has a window region, a conductive region that substantially surrounds the window region, a circular patch antenna that is in communication with the IC, and an elliptical patch antenna that is located within the window region, that is extends over at least a portion of the circular patch antenna, and that is in communication with the circular patch antenna. The HIS substantially surrounds the antenna assembly.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: May 31, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Eunyoung Seok, Srinath Ramaswamy, Brian B. Ginsburg, Vijay B. Rentala, Baher Haroun
  • Patent number: 8942643
    Abstract: An apparatus is provided. A plurality of transceiver antennas are arranged to form a phased array, where each antenna include a differential transmit antenna and a differential receive antenna arranged in a first pattern. A plurality of transceivers are arranged in a second pattern that is substantially symmetrical, and each transceiver is associated with at least one of the transceiver antennas and includes a feed network. Each feed network has a power amplifier (PA), a first matching network that is coupled between the PA and its associated transmit antenna so as to translate the phase of each differential transmit signal, a low noise amplifier (LNA), and a second matching network that is coupled between the LNA and its associated receive antenna so as to translate the phase of each differential receive signal.
    Type: Grant
    Filed: September 7, 2011
    Date of Patent: January 27, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Brian P. Ginsburg, Eunyoung Seok, Vijay B. Rentala, Srinath Ramaswamy, Baher Haroun