Patents by Inventor Christian Lindholm

Christian Lindholm 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: 20240007117
    Abstract: A multi-step analog-to-digital converter (ADC). The ADC includes a sampling circuitry, a comparator, a trimming circuitry, and a DC offset actuator. The sampling circuitry is configured to sample an input analog signal. The comparator is for comparing the input analog signal sample or a residual component of the input analog signal sample to a reference value in each step. The trimming circuitry is configured to receive at least one low-order bit (e.g., a least significant bit and/or a second-least significant bit) of digital binary bits of each input analog signal sample and average the low order bit over a plurality of input analog signal samples and generate a control signal for correcting an input DC offset of the comparator based on an average value of the low-order bits. The DC offset actuator is configured to correct the input DC offset of the comparator based on the control signal.
    Type: Application
    Filed: June 29, 2022
    Publication date: January 4, 2024
    Inventors: Michael FULDE, Harneet KHURANA, Matteo CAMPONESCHI, Patrizia GRECO, Christian LINDHOLM, Martin CLARA, Giacomo CASCIO
  • Publication number: 20230208427
    Abstract: A successive approximation register (SAR) analog-to-digital converter (ADC) includes a plurality of differential capacitive digital-to-analog converters (C-DACs), comparators, and an SAR controller. Each differential C-DAC comprises a pair of C-DACs for positive and negative polarities and each C-DAC comprises a capacitor array. A capacitor for each bit position may include a pair of equal-sized capacitors. Each outer comparator is coupled to one of the differential C-DACs and the middle comparator is coupled to a differential output node pair of C-DACs from two differential C-DACs. The SAR controller generates a control signal for the differential C-DACs for each conversion step based on outputs of the comparators. The outputs of the comparators are provided to the differential C-DACs as the control signal without encoding. Single-bit/cycle shorting switches for shorting top plates of capacitors of the C-DACs of same polarity may be closed during a single-bit/cycle conversion.
    Type: Application
    Filed: December 23, 2021
    Publication date: June 29, 2023
    Inventors: Michael FULDE, Harneet KHURANA, Matteo CAMPONESCHI, Patrizia GRECO, Christian LINDHOLM, Martin CLARA, Giacomo CASCIO
  • Patent number: 11601121
    Abstract: The present disclosure relates to a bootstrapped switch circuit, a track-and-hold circuit, an analog-to-digital converter, a method for operating a track-and-hold circuit, a base station, and a mobile station. The bootstrapped switch circuit comprises an output for an output signal, a first input, a switching element configured to couple the output with a signal from the first input, a bootstrapper capacitor configured to drive the switching element, and a second input coupled to the bootstrapper capacitor.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: March 7, 2023
    Assignee: Intel Corporation
    Inventors: Giacomo Cascio, Martin Clara, Christian Lindholm
  • Publication number: 20220416800
    Abstract: An apparatus for analog-to-digital conversion is provided. The apparatus includes a first analog-to-digital converter (ADC) configured to receive an input signal and convert the input signal to a sequence of M-bit digital values. The apparatus further includes a second ADC including a plurality of time-interleaved sub-ADCs each being configured to receive the input signal and at least one M-bit digital value of the sequence of M-bit digital values. Further, each of the plurality of time-interleaved sub-ADCs is configured to convert the input signal to a respective sequence of B-bit digital values using the at least one M-bit digital value of the sequence of M-bit digital values. M and B are integers with M<B.
    Type: Application
    Filed: June 25, 2021
    Publication date: December 29, 2022
    Inventors: Martin CLARA, Daniel GRUBER, Christian LINDHOLM, Michael FULDE, Giacomo CASCIO
  • Patent number: 11528182
    Abstract: An Analog-to-Digital Converter, ADC, system is provided. The ADC system comprises a plurality of ADC circuits and a first input for receiving a transmit signal of a transceiver. One ADC circuit of the plurality of ADC circuits is coupled to the first input and configured to provide first digital data based on the transmit signal. The ADC system further comprises a second input for receiving a receive signal of the transceiver. The other ADC circuits of the plurality of ADC circuits are coupled to the second input, wherein the other ADC circuits of the plurality of ADC circuits are time-interleaved and configured to provide second digital data based on the receive signal. Additionally, the ADC system comprises a first output configured to output digital feedback data based on the first digital data, and a second output configured to output digital receive data based on the second digital data.
    Type: Grant
    Filed: June 18, 2021
    Date of Patent: December 13, 2022
    Assignee: INTEL CORPORATION
    Inventors: Kameran Azadet, Martin Clara, Daniel Gruber, Christian Lindholm, Hundo Shin
  • Patent number: 11489538
    Abstract: A circuit having an array of Analog-to-Digital Converters (ADCs); a sampling order selector configured to select a sampling order of the ADCs and output corresponding sampling order control words; sampling pulse generators coupled between the sampling order selector and the respective ADCs, and configured to output respective sampling pulses based on the respective sampling order control words, wherein the ADCs are configured to sample and convert analog data into digital data in response to the sampling pulses; and a single clock generator configured to distribute a delay-matched clock to each of the ADCs in parallel, to each of the sampling pulse generators in parallel, and to the sampling order selector.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: November 1, 2022
    Assignee: Intel Corporation
    Inventors: Edwin Thaller, Christian Lindholm
  • Publication number: 20220345146
    Abstract: An analog-to-digital converter comprising a plurality of sampling cells. At least one of the plurality of sampling cells comprises a capacitive element coupled to a cell output of the at least one of the plurality of sampling cells, wherein a cell output signal is provided at the cell output. The at least one of the plurality of sampling cells further comprises a first cell input for receiving an input signal to be digitized, and a second cell input for receiving a calibration signal. Additionally, the at least one of the plurality of sampling cells comprises a first switch circuit capable of selectively coupling the first cell input to the capacitive element based on a clock signal, and a second switch circuit capable of selectively coupling the second cell input to the capacitive element, wherein a size of the second switch circuit is smaller than a size of the first switch circuit.
    Type: Application
    Filed: December 27, 2019
    Publication date: October 27, 2022
    Inventors: Albert MOLINA, Kameran AZADET, Martin CLARA, Matteo CAMPONESCHI, Christian LINDHOLM
  • Publication number: 20220197844
    Abstract: A bootstrapping circuit for a semiconductor switch is provided. The bootstrapping circuit includes a capacitor, a first node for coupling to an input node of the semiconductor switch, and a second node for coupling to a control node of the semiconductor switch. Further, the bootstrapping circuit includes a switch circuit configured to selectively couple the capacitor to a charge source while the semiconductor switch is open and to selectively close a conductive path between the first node and the second node for closing the semiconductor switch. The conductive path includes the capacitor. The bootstrapping circuit additionally includes charge injection circuitry configured to inject charge into the conductive path before, while or after the conductive path is closed by the switch circuit.
    Type: Application
    Filed: December 23, 2020
    Publication date: June 23, 2022
    Inventors: Christian LINDHOLM, Giacomo CASCIO, Martin CLARA, Daniel GRUBER
  • Publication number: 20220200615
    Abstract: A reference buffer circuit for an analog-to-digital converter is provided. The reference buffer circuit includes a first input node configured to receive a first bias signal of a first polarity from a first signal line. Further, the reference buffer circuit includes a second input node configured to receive a second bias signal of a second polarity from a second signal line. Additionally, the reference buffer circuit includes a first output node configured to output a first reference signal of the first polarity. A first buffer amplifier is coupled between the first input node and the first output node. The reference buffer circuit includes in addition a second output node configured to output a second reference signal of the second polarity. A second buffer amplifier is coupled between the second input node and the second output node. Further, the reference buffer circuit includes a first coupling path comprising a first capacitive element.
    Type: Application
    Filed: December 23, 2020
    Publication date: June 23, 2022
    Inventors: Daniel GRUBER, Christian LINDHOLM, Martin CLARA, Giacomo CASCIO
  • Publication number: 20220200616
    Abstract: A method and system for controlling an analog-to-digital converter (ADC) in an observation path in a transceiver. The transceiver includes a transmit path, a receive path, and an observation path. The observation path includes an analog buffer and an observation ADC. A controller generates a control signal to control sampling events at the observation ADC to activate the observation ADC at combined uniform and non-uniform sampling instants. The controller may also generate a second control signal indicating whether digital data obtained by the observation ADC is valid or not. The digital data generated by the observation ADC at non-uniform sampling instants is indicated as invalid and digital data generated by the observation ADC at uniform sampling instants is indicated as valid. The digital data indicated as invalid may be discarded and the digital data indicated as valid is used for calibration of the transmit path or the receive path.
    Type: Application
    Filed: December 23, 2020
    Publication date: June 23, 2022
    Inventors: Matteo CAMPONESCHI, Albert MOLINA, Kannan RAJAMANI, Giacomo CASCIO, Christian LINDHOLM
  • Publication number: 20220200613
    Abstract: An input buffer circuit for an analog-to-digital converter is provided. The input buffer circuit includes a buffer amplifier. The buffer amplifier includes a first input node and a second input node each configured to receive a respective one of a first input signal and a second input signal forming a differential input signal pair for the analog-to-digital converter. The buffer amplifier further includes a first output node and a second output node each configured to output a respective one of a first buffered signal and a second buffered signal. In addition, the input buffer circuit includes feedback circuitry. The feedback circuitry is configured to generate, based on the first buffered signal and the second buffered signal, a first feedback signal and a second feedback signal for mitigating a respective unwanted signal component at the first input node and the second input node related to a limited reverse isolation of the amplifier buffer.
    Type: Application
    Filed: December 23, 2020
    Publication date: June 23, 2022
    Inventors: Daniel GRUBER, Matteo CAMPONESCHI, Christian LINDHOLM, Martin CLARA, Giacomo CASCIO
  • Patent number: 11277146
    Abstract: An analog-to-digital converter (ADC) configured to convert an analog signal to digital bits. The ADC includes a plurality of sub-ADCs that are cascaded in a pipeline. Each sub-ADC may be configured to sample an input signal that is fed to each sub-ADC and convert the sampled input signal to a pre-configured number of digital bits. Each sub-ADC except a last sub-ADC in the pipeline is configured to generate a residue signal and feed the residue signal as the input signal to a succeeding sub-ADC in the pipeline. At least one sub-ADC is configured to determine a most-significant bit (MSB) of the pre-configured number of digital bits while the input signal is sampled. The ADC may include a plurality of residue amplifiers for amplifying a residue signal. The sub-ADCs may be successive approximation register (SAR) ADCs or flash ADCs.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: March 15, 2022
    Assignee: Intel Corporation
    Inventors: Christian Lindholm, Hundo Shin, Martin Clara
  • Patent number: 11271578
    Abstract: A time-interleaved Analog-to-Digital Converter, ADC, system is provided. The time-inter-leaved ADC system includes time-interleaved first and second ADC circuits and a switching circuit. The switching circuit is configured to selectively supply an analog input signal for digitization to at least one of the first ADC circuit, the second ADC circuit or ground, and to selectively supply an analog calibration signal to at least one of the first ADC circuit, the second ADC circuit or ground. Further, the time-interleaved ADC system includes an output circuit configured to selectively generate, based on least one of a first digital signal output by the first ADC circuit and a second digital signal output by the second ADC circuit, a digital output signal.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: March 8, 2022
    Assignee: Intel Corporation
    Inventors: Albert Molina, Kameran Azadet, Matteo Camponeschi, Jose Luis Ceballos, Christian Lindholm
  • Publication number: 20210409035
    Abstract: An analog-to-digital converter (ADC) configured to convert an analog signal to digital bits. The ADC includes a plurality of sub-ADCs that are cascaded in a pipeline. Each sub-ADC may be configured to sample an input signal that is fed to each sub-ADC and convert the sampled input signal to a pre-configured number of digital bits. Each sub-ADC except a last sub-ADC in the pipeline is configured to generate a residue signal and feed the residue signal as the input signal to a succeeding sub-ADC in the pipeline. At least one sub-ADC is configured to determine a most-significant bit (MSB) of the pre-configured number of digital bits while the input signal is sampled. The ADC may include a plurality of residue amplifiers for amplifying a residue signal. The sub-ADCs may be successive approximation register (SAR) ADCs or flash ADCs.
    Type: Application
    Filed: June 26, 2020
    Publication date: December 30, 2021
    Inventors: Christian Lindholm, Hundo Shin, Martin Clara
  • Publication number: 20210409015
    Abstract: The present disclosure relates to a bootstrapped switch circuit, a track-and-hold circuit, an analog-to-digital converter, a method for operating a track-and-hold circuit, a base station, and a mobile station. The bootstrapped switch circuit comprises an output for an output signal, a first input, a switching element configured to couple the output with a signal from the first input, a bootstrapper capacitor configured to drive the switching element, and a second input coupled to the bootstrapper capacitor.
    Type: Application
    Filed: June 26, 2020
    Publication date: December 30, 2021
    Inventors: Giacomo Cascio, Martin Clara, Christian Lindholm
  • Publication number: 20210385119
    Abstract: An Analog-to-Digital Converter, ADC, system is provided. The ADC system comprises a plurality of ADC circuits and a first input for receiving a transmit signal of a transceiver. One ADC circuit of the plurality of ADC circuits is coupled to the first input and configured to provide first digital data based on the transmit signal. The ADC system further comprises a second input for receiving a receive signal of the transceiver. The other ADC circuits of the plurality of ADC circuits are coupled to the second input, wherein the other ADC circuits of the plurality of ADC circuits are time-interleaved and configured to provide second digital data based on the receive signal. Additionally, the ADC system comprises a first output configured to output digital feedback data based on the first digital data, and a second output configured to output digital receive data based on the second digital data.
    Type: Application
    Filed: June 18, 2021
    Publication date: December 9, 2021
    Inventors: Kameran AZADET, Martin CLARA, Daniel GRUBER, Christian LINDHOLM, Hundo SHIN
  • Publication number: 20210367607
    Abstract: A time-interleaved Analog-to-Digital Converter, ADC, system is provided. The time-inter- leaved ADC system includes time-interleaved first and second ADC circuits and a switching circuit. The switching circuit is configured to selectively supply an analog input signal for digitization to at least one of the first ADC circuit, the second ADC circuit or ground, and to selectively supply an analog calibration signal to at least one of the first ADC circuit, the second ADC circuit or ground. Further, the time-interleaved ADC system includes an output circuit configured to selectively generate, based on least one of a first digital signal output by the first ADC circuit and a second digital signal output by the second ADC circuit, a digital output signal.
    Type: Application
    Filed: March 29, 2019
    Publication date: November 25, 2021
    Inventors: Albert MOLINA, Kameran AZADET, Matteo CAMPONESCHI, Jose Luis CEBALLOS, Christian LINDHOLM
  • Patent number: 11177820
    Abstract: A n-bit Successive Approximation Register Analog-to-Digital Converter, SAR ADC, is provided. The SAR ADC comprises a respective plurality of sampling cells for each bit of the n-bit of the SAR ADC. Each sampling cell comprises a capacitive element coupled to a cell output of the sampling cell in order to provide a cell output signal. Further, each sampling cell comprises a first cell input for receiving a first signal, and a first switch circuit capable of selectively coupling the first cell input to the capacitive element. Each cell additionally comprises a second cell input for receiving a second signal, and a third cell input for receiving a third signal. The third signal exhibits opposite polarity compared to the second signal. Each sampling cell comprises a second switch circuit capable of selectively coupling one of the second cell input and the third cell input to the capacitive element. The SAR ADC further comprises at least one comparator circuit coupled to the sampling cells.
    Type: Grant
    Filed: July 20, 2020
    Date of Patent: November 16, 2021
    Assignee: Intel Corporation
    Inventors: Albert Molina, Martin Clara, Matteo Camponeschi, Christian Lindholm, Kameran Azadet
  • Patent number: 11082054
    Abstract: The present disclosure relates to a time-interleaved ADC circuit. The time-interleaved ADC circuit comprises an input for an analog input signal, a first ADC bank comprising a first plurality of parallel time-multiplexed ADCs, wherein the first plurality of parallel time-multiplexed ADCs is configured to subsequently generate a first plurality of samples of the analog input signal during a first time interval, a first buffer amplifier coupled between the input and the first ADC bank. The time-interleaved ADC circuit further comprises a second ADC bank comprising a second plurality of parallel time-multiplexed ADCs, wherein the second plurality of parallel time-multiplexed ADCs is configured to subsequently generate a second plurality of samples of the analog input signal during a second time interval, wherein the first and the second time intervals are subsequent time intervals, a second buffer amplifier coupled between the input and the second ADC bank.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: August 3, 2021
    Assignee: Intel Corporation
    Inventors: Giacomo Cascio, Christian Lindholm, Albert Molina, Martin Clara
  • Publication number: 20210218410
    Abstract: A circuit having an array of Analog-to-Digital Converters (ADCs); a sampling order selector configured to select a sampling order of the ADCs and output corresponding sampling order control words; sampling pulse generators coupled between the sampling order selector and the respective ADCs, and configured to output respective sampling pulses based on the respective sampling order control words, wherein the ADCs are configured to sample and convert analog data into digital data in response to the sampling pulses; and a single clock generator configured to distribute a delay-matched clock to each of the ADCs in parallel, to each of the sampling pulse generators in parallel, and to the sampling order selector.
    Type: Application
    Filed: September 28, 2018
    Publication date: July 15, 2021
    Inventors: Edwin Thaller, Christian Lindholm