Patents by Inventor Rohit Ranganathan

Rohit Ranganathan 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: 11692872
    Abstract: An optical light sensing device includes a detector operable to detect a light wave. The optical light sensing device also includes an integration circuit that includes an operational amplifier that is operable to reduce or cancel dark currents generated at the detector.
    Type: Grant
    Filed: July 29, 2020
    Date of Patent: July 4, 2023
    Assignee: AMS INTERNATIONAL AG
    Inventors: Ravi Kumar Adusumalli, Rohit Ranganathan, Vijay Ele
  • Patent number: 11549900
    Abstract: A sensor arrangement includes a switchable voltage source having a source output for alternatively providing a first and a second excitation voltage, an integrator having an integrator input and an integrator output, a sensor resistor having a first terminal coupled to the source output, a reference resistor having a first terminal coupled to a second terminal of the sensor resistor and a second terminal coupled to the integrator input, and a comparator having a first comparator input coupled to the integrator output.
    Type: Grant
    Filed: May 16, 2019
    Date of Patent: January 10, 2023
    Assignee: AMS INTERNATIONAL AG
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli
  • Publication number: 20220299362
    Abstract: An optical light sensing device includes a detector operable to detect a light wave. The optical light sensing device also includes an integration circuit that includes an operational amplifier that is operable to reduce or cancel dark currents generated at the detector.
    Type: Application
    Filed: July 29, 2020
    Publication date: September 22, 2022
    Inventors: Ravi Kumar Adusumalli, Rohit Ranganathan, Vijay Ele
  • Patent number: 11448609
    Abstract: In an embodiment a method for operating a gas sensor arrangement includes generating a sensor current by a gas sensor, converting the sensor current into a digital comparator output signal in a charge balancing operation depending on a first clock signal, determining from the digital comparator output signal an asynchronous count comprising an integer number of counts depending on the first clock signal, determining from the digital comparator output signal a fractional time count depending on a second clock signal and calculating from the asynchronous count and from the fractional time count a digital output signal which is indicative of the sensor current generated by the gas sensor.
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: September 20, 2022
    Assignee: SCIOSENSE B.V.
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli
  • Patent number: 11418208
    Abstract: A method for light-to-digital conversion includes setting a time integrator circuit into a reference condition and starting to integrate charge from a sensor device for the duration of an integration time. An integration signal is generated and is indicative of the integrated charge. The integration signal is compared with an adjustable reference signal. A first count is generated when the comparison indicates that the integration signal has reached an integration range, wherein the integration range is defined by a low and a high voltage. A second count is generated when the comparison indicates that the integration signal has reached the adjustable reference signal. The adjustable reference signal is incremented in discrete steps when a second count has been generated. Then, the time integrator circuit is reset into the reference condition, when the comparison indicates that the integration signal has reached the integration range.
    Type: Grant
    Filed: April 16, 2019
    Date of Patent: August 16, 2022
    Assignee: AMS AG
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli, Dinesh Kuruganti
  • Patent number: 11268852
    Abstract: A method for light-to-frequency conversion comprises the steps of illuminating a photodiode by a light source, generating a photocurrent by means of the photodiode, converting the photocurrent into a digital comparator output signal depending on a first clock signal, generating a first count comprising an integer number of counts, where the generation of the first count depends on the first clock signal, generating a second count which relates to the time interval between at least two counts of the first count, and determining the frequency of a repeating pattern in the intensity of electromagnetic radiation emitted by the light source and detected by the photodiode from the first count and the second count. Furthermore, a light-to-frequency converter arrangement is provided.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: March 8, 2022
    Assignee: AMS INTERNATIONAL AG
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli, Dinesh Kuruganti
  • Patent number: 11199516
    Abstract: A measurement circuitry (MC) for evaluating a resistance of a resistive gas sensor (GS) comprises a first current path (P1), wherein a first logarithmic compression circuit (LC1) is arranged in the first current path (P1). A reference resistor (Rreference) and a second logarithmic compression circuit (LC2) is arranged in a second current path (P2) of the measurement circuitry (MC). A voltage generator (VG) provides a fixed voltage excitation for the resistive gas sensor (GS) and the reference resistor (Rreference). A first current (I1) received from the resistive gas sensor (GS) flows from the gas sensor (GS) via the first current path (P1) into the first logarithmic compression circuit (LC1). An evaluation circuit (EC) determines the resistance (Rs) of the resistive gas sensor (GS) in dependence on a first and second output signal (Ve1, Ve2) of the first and the second logarithmic compression circuit (LC1, LC2).
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: December 14, 2021
    Assignee: AMS INTERNATIONAL AG
    Inventors: Rohit Ranganathan, Sanjeev Praphulla Chandra Nyshadham, Krishna Kanth Avalur, Ravi Kumar Adusumalli, Prasad Ponnada
  • Patent number: 11047733
    Abstract: A method for light-to-frequency conversion comprises generating a photocurrent by means of a photodiode and converting the photocurrent into a digital comparator output signal in a charge balancing operation depending on a first clock signal. From the digital comparator output signal an asynchronous count is determined and comprises an integer number of counts depending on the first clock signal. From the digital comparator output signal a fractional time count is determined and depends on a second clock signal. Finally, from the asynchronous count and from the fractional time count a digital output signal is calculated which is indicative of the photocurrent generated by the photodiode. The method may be carried out by an exemplary light-to-frequency converter equipped with a photodiode.
    Type: Grant
    Filed: March 1, 2018
    Date of Patent: June 29, 2021
    Assignee: AMS INTERNATIONAL AG
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli
  • Publication number: 20210190712
    Abstract: A sensor arrangement includes a switchable voltage source having a source output for alternatively providing a first and a second excitation voltage, an integrator having an integrator input and an integrator output, a sensor resistor having a first terminal coupled to the source output, a reference resistor having a first terminal coupled to a second terminal of the sensor resistor and a second terminal coupled to the integrator input, and a comparator having a first comparator input coupled to the integrator output.
    Type: Application
    Filed: May 16, 2019
    Publication date: June 24, 2021
    Inventors: Rohit RANGANATHAN, Ravi Kumar ADUSUMALLI
  • Publication number: 20210105020
    Abstract: A method for light-to-digital conversion includes setting a time integrator circuit into a reference condition and starting to integrate charge from a sensor device for the duration of an integration time. An integration signal is generated and is indicative of the integrated charge. The integration signal is compared with an adjustable reference signal. A first count is generated when the comparison indicates that the integration signal has reached an integration range, wherein the integration range is defined by a low and a high voltage. A second count is generated when the comparison indicates that the integration signal has reached the adjustable reference signal. The adjustable reference signal is incremented in discrete steps when a second count has been generated. Then, the time integrator circuit is reset into the reference condition, when the comparison indicates that the integration signal has reached the integration range.
    Type: Application
    Filed: April 16, 2019
    Publication date: April 8, 2021
    Inventors: Rohit RANGANATHAN, Ravi Kumar ADUSUMALLI, Dinesh KURUGANTI
  • Publication number: 20210088380
    Abstract: A method for light-to-frequency conversion comprises the steps of illuminating a photodiode by a light source, generating a photocurrent by means of the photodiode, converting the photocurrent into a digital comparator output signal depending on a first clock signal, generating a first count comprising an integer number of counts, where the generation of the first count depends on the first clock signal, generating a second count which relates to the time interval between at least two counts of the first count, and determining the frequency of a repeating pattern in the intensity of electromagnetic radiation emitted by the light source and detected by the photodiode from the first count and the second count. Furthermore, a light-to-frequency converter arrangement is provided.
    Type: Application
    Filed: March 13, 2019
    Publication date: March 25, 2021
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli, Dinesh KURUGANTI
  • Patent number: 10826523
    Abstract: An analog-to-digital converter (10) comprises a first and a second sampling capacitor (24, 25), a first integrator (26), a first and a second input switch (31, 32) coupling a first input terminal (11) and a common mode terminal (39) to a first electrode of the first sampling capacitor (24), a third and a fourth input switch (33, 34) coupling a second input terminal (12) and the common mode terminal (39) to a first electrode of the second sampling capacitor (25), a fifth and a sixth input switch (35, 36) coupling a second electrode of the first sampling capacitor (24) to an amplifier common mode terminal (40) and the first integrator input (27), and a seventh and an eighth input switch (37, 38) coupling a second electrode of the second sampling capacitor (25) to the amplifier common mode terminal (40) and the second integrator input (28).
    Type: Grant
    Filed: May 4, 2018
    Date of Patent: November 3, 2020
    Assignee: ams AG
    Inventors: Ravi Kumar Adusumalli, Sudhakar Singamala, Veeresh Babu Vulligaddala, Rohit Ranganathan, Chandra Nyshadham, Krishna Kanth Avalur, Parvathy Sasikala Jayachandran Pillai
  • Publication number: 20200240941
    Abstract: A method for operating a gas sensor arrangement comprises generating a sensor current by means of a gas sensor and converting the sensor current into a digital comparator output signal in a charge balancing operation depending on a first clock signal. An asynchronous count comprising an integer number of counts is determined from the digital comparator output signal and depending on the first clock signal. Furthermore, a fractional time count depending on a second clock signal is determined from the digital comparator output signal. Finally, a digital output signal is calculated from the asynchronous count and from the fractional time count. The digital output signal is indicative of the sensor current generated by the gas sensor.
    Type: Application
    Filed: July 18, 2018
    Publication date: July 30, 2020
    Inventors: Rohit Ranganathan, Ravi Kumar ADUSUMALLI
  • Publication number: 20200083901
    Abstract: An analog-to-digital converter (10) comprises a first and a second sampling capacitor (24, 25), a first integrator (26), a first and a second input switch (31, 32) coupling a first input terminal (11) and a common mode terminal (39) to a first electrode of the first sampling capacitor (24), a third and a fourth input switch (33, 34) coupling a second input terminal (12) and the common mode terminal (39) to a first electrode of the second sampling capacitor (25), a fifth and a sixth input switch (35, 36) coupling a second electrode of the first sampling capacitor (24) to an amplifier common mode terminal (40) and the first integrator input (27), and a seventh and an eighth input switch (37, 38) coupling a second electrode of the second sampling capacitor (25) to the amplifier common mode terminal (40) and the second integrator input (28).
    Type: Application
    Filed: May 4, 2018
    Publication date: March 12, 2020
    Inventors: Ravi Kumar ADUSUMALLI, Sudhakar Singamala, Veeresh Babu VULLIGADDALA, Rohit RANGANATHAN, Chandra NYSHADHAM, Krishna Kanth AVALUR, Parvathy SASIKALA JAYACHANDRAN PILLAI
  • Publication number: 20200033284
    Abstract: A measurement circuitry (MC) for evaluating a resistance of a resistive gas sensor (GS) comprises a first current path (P1), wherein a first logarithmic compression circuit (LC1) is arranged in the first current path (P1). A reference resistor (Rreference) and a second logarithmic compression circuit (LC2) is arranged in a second current path (P2) of the measurement circuitry (MC). A voltage generator (VG) provides a fixed voltage excitation for the resistive gas sensor (GS) and the reference resistor (Rreference). A first current (I1) received from the resistive gas sensor (GS) flows from the gas sensor (GS) via the first current path (P1) into the first logarithmic compression circuit (LC1). An evaluation circuit (EC) determines the resistance (Rs) of the resistive gas sensor (GS) in dependence on a first and second output signal (Ve1, Ve2) of the first and the second logarithmic compression circuit (LC1, LC2).
    Type: Application
    Filed: September 6, 2017
    Publication date: January 30, 2020
    Inventors: Rohit RANGANATHAN, Sanjeev Praphulla Chandra NYSHADHAM, Krishna Kanth AVALUR, Ravi Kumar ADUSUMALLI, Prasad PONNADA
  • Publication number: 20200003616
    Abstract: A method for light-to-frequency conversion comprises generating a photocurrent by means of a photodiode and converting the photocurrent into a digital comparator output signal in a charge balancing operation depending on a first clock signal. From the digital comparator output signal an asynchronous count is determined and comprises an integer number of counts depending on the first clock signal. From the digital comparator output signal a fractional time count is determined and depends on a second clock signal. Finally, from the asynchronous count and from the fractional time count a digital output signal is calculated which is indicative of the photocurrent generated by the photodiode. The method may be carried out by an exemplary light-to-frequency converter equipped with a photodiode.
    Type: Application
    Filed: March 1, 2018
    Publication date: January 2, 2020
    Inventors: Rohit Ranganathan, Ravi Kumar Adusumalli