公开(公告)号：US11199516B2

公开(公告)日：2021-12-14

申请号：US16337498

申请日：2017-09-06

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Sanjeev Praphulla Chandra Nyshadham ,  Krishna Kanth Avalur ,  Ravi Kumar Adusumalli ,  Prasad Ponnada

IPC: G01N27/12

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).

公开(公告)号：US20210088380A1

公开(公告)日：2021-03-25

申请号：US16971035

申请日：2019-03-13

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Ravi Kumar Adusumalli ,  Dinesh KURUGANTI

IPC: G01J1/46

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.

公开(公告)号：US11692872B2

公开(公告)日：2023-07-04

申请号：US17619943

申请日：2020-07-29

Applicant: AMS INTERNATIONAL AG

Inventor： Ravi Kumar Adusumalli ,  Rohit Ranganathan ,  Vijay Ele

IPC: G01J1/44 ,  H03F3/45 ,  G01J1/42 ,  H03F3/38 ,  H03M1/06

CPC classification number: G01J1/44 ,  H03F3/45475 ,  G01J2001/446

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.

公开(公告)号：US11549900B2

公开(公告)日：2023-01-10

申请号：US17055898

申请日：2019-05-16

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Ravi Kumar Adusumalli

IPC: G01N27/12 ,  G01N27/04 ,  G01R27/14 ,  H03M1/06

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.

公开(公告)号：US20220299362A1

公开(公告)日：2022-09-22

申请号：US17619943

申请日：2020-07-29

Applicant: AMS INTERNATIONAL AG

Inventor： Ravi Kumar Adusumalli ,  Rohit Ranganathan ,  Vijay Ele

IPC: G01J1/44 ,  H03F3/45

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.

公开(公告)号：US11268852B2

公开(公告)日：2022-03-08

申请号：US16971035

申请日：2019-03-13

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Ravi Kumar Adusumalli ,  Dinesh Kuruganti

IPC: G01J1/46 ,  G01J1/42 ,  G01J1/44

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.

公开(公告)号：US11047733B2

公开(公告)日：2021-06-29

申请号：US16489256

申请日：2018-03-01

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Ravi Kumar Adusumalli

IPC: G01J1/44 ,  H03M1/60

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.

公开(公告)号：US20200003616A1

公开(公告)日：2020-01-02

申请号：US16489256

申请日：2018-03-01

Applicant: ams International AG

Inventor： Rohit Ranganathan ,  Ravi Kumar Adusumalli

IPC: G01J1/44 ,  H03M1/60

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.