Patents by Inventor Stefan Barabas

Stefan Barabas 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: 11973471
    Abstract: The present disclosure provides for process and temperature compensation in a transimpedance amplifier (TIA) using a dual replica via monitoring an output of a first TIA (transimpedance amplifier) and a second TIA; configuring a first gain level of the first TIA based on a feedback resistance and a reference current applied at an input to the first TIA; configuring a second gain level of the second TIA and a third TIA based on a control voltage; and amplifying a received electrical current to generate an output voltage using the third TIA according to the second gain level. In some embodiments, one or both of the second TIA and the third TIA include a configurable feedback impedance used in compensating for changes in the second gain level due to a temperature of the respective second or third TIA via the configurable feedback impedance of the respective second or third TIA.
    Type: Grant
    Filed: January 24, 2023
    Date of Patent: April 30, 2024
    Assignee: Cisco Technology, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Patent number: 11588445
    Abstract: The present disclosure provides for process and temperature compensation in a transimpedance amplifier (TIA) using a dual replica via monitoring an output of a first TIA (transimpedance amplifier) and a second TIA; configuring a first gain level of the first TIA based on a feedback resistance and a reference current applied at an input to the first TIA; configuring a second gain level of the second TIA and a third TIA based on a control voltage; and amplifying a received electrical current to generate an output voltage using the third TIA according to the second gain level. In some embodiments, one or both of the second TIA and the third TIA include a configurable feedback impedance used in compensating for changes in the second gain level due to a temperature of the respective second or third TIA via the configurable feedback impedance of the respective second or third TIA.
    Type: Grant
    Filed: October 15, 2020
    Date of Patent: February 21, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20210028748
    Abstract: The present disclosure provides for process and temperature compensation in a transimpedance amplifier (TIA) using a dual replica via monitoring an output of a first TIA (transimpedance amplifier) and a second TIA; configuring a first gain level of the first TIA based on a feedback resistance and a reference current applied at an input to the first TIA; configuring a second gain level of the second TIA and a third TIA based on a control voltage; and amplifying a received electrical current to generate an output voltage using the third TIA according to the second gain level. In some embodiments, one or both of the second TIA and the third TIA include a configurable feedback impedance used in compensating for changes in the second gain level due to a temperature of the respective second or third TIA via the configurable feedback impedance of the respective second or third TIA.
    Type: Application
    Filed: October 15, 2020
    Publication date: January 28, 2021
    Inventors: Stefan BARABAS, Joseph BALARDETA, Simon PANG, Scott DENTON
  • Patent number: 10855229
    Abstract: Methods and systems for process and temperature compensation in a transimpedance amplifier using a dual replica and configurable impedances is disclosed and may include a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, a third TIA, and a control loop. The first TIA comprises a fixed feedback resistance and the second and third TIAs each comprise a configurable feedback impedance. The system may comprise a gain stage with inputs coupled to outputs of the first and second TIAs and with an output coupled to the configurable feedback impedance of the second and third TIAs. The circuit may be operable to configure a gain level of the first TIA based on the fixed feedback resistance and a reference current applied at an input to the first TIA, and configure a gain level of the second and third TIAs based on a control voltage generated by the gain stage.
    Type: Grant
    Filed: June 3, 2019
    Date of Patent: December 1, 2020
    Assignee: Luxtera LLC
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Patent number: 10721035
    Abstract: Methods and systems for an optoelectronic built-in self-test (BIST) system for silicon photonics optical transceivers may include an optoelectronic transceiver having a transmit (Tx) path and a receive (Rx) path, where the Rx path includes a main Rx path and a BIST loopback path. The system may generate a pseudo-random bit sequence (PRBS) signal, generate an optical signal in the Tx path by applying the PRBS signal to a modulator, communicate the optical signal to the BIST loopback path and convert the optical signal to an electrical signal utilizing a photodetector, where the photodetector is a replica of a photodetector in the main Rx path, and assess the performance of the Tx and Rx paths by extracting a PRBS signal from the electrical signal. The transceiver may be on a single complementary-metal oxide semiconductor (CMOS) die, or on two CMOS die where a first comprises electronic devices and a second comprises optical devices.
    Type: Grant
    Filed: July 3, 2019
    Date of Patent: July 21, 2020
    Assignee: Luxtera LLC
    Inventors: Steffen Gloeckner, Subal Sahni, Joseph Balardeta, Simon Pang, Stefan Barabas, Scott Denton
  • Patent number: 10615759
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Grant
    Filed: November 21, 2018
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20190327036
    Abstract: Methods and systems for an optoelectronic built-in self-test (BIST) system for silicon photonics optical transceivers may include an optoelectronic transceiver having a transmit (Tx) path and a receive (Rx) path, where the Rx path includes a main Rx path and a BIST loopback path. The system may generate a pseudo-random bit sequence (PRBS) signal, generate an optical signal in the Tx path by applying the PRBS signal to a modulator, communicate the optical signal to the BIST loopback path and convert the optical signal to an electrical signal utilizing a photodetector, where the photodetector is a replica of a photodetector in the main Rx path, and assess the performance of the Tx and Rx paths by extracting a PRBS signal from the electrical signal. The transceiver may be on a single complementary-metal oxide semiconductor (CMOS) die, or on two CMOS die where a first comprises electronic devices and a second comprises optical devices.
    Type: Application
    Filed: July 3, 2019
    Publication date: October 24, 2019
    Inventors: Steffen Gloeckner, Subal Sahni, Joseph Balardeta, Simon Pang, Stefan Barabas, Scott Denton
  • Publication number: 20190305731
    Abstract: Methods and systems for process and temperature compensation in a transimpedance amplifier using a dual replica and configurable impedances is disclosed and may include a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, a third TIA, and a control loop. The first TIA comprises a fixed feedback resistance and the second and third TIAs each comprise a configurable feedback impedance. The system may comprise a gain stage with inputs coupled to outputs of the first and second TIAs and with an output coupled to the configurable feedback impedance of the second and third TIAs. The circuit may be operable to configure a gain level of the first TIA based on the fixed feedback resistance and a reference current applied at an input to the first TIA, and configure a gain level of the second and third TIAs based on a control voltage generated by the gain stage.
    Type: Application
    Filed: June 3, 2019
    Publication date: October 3, 2019
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Patent number: 10348459
    Abstract: Methods and systems for an optoelectronic built-in self-test (BIST) system for silicon photonics optical transceivers are disclosed and may include, in an optoelectronic transceiver having a transmit (Tx) path and a receive (Rx) path, where the Rx path includes a main Rx path and a BIST loopback path: generating a pseudo-random bit sequence (PRBS) signal, generating an optical signal in the Tx path by applying the PRBS signal to a modulator, communicating the optical signal to the BIST loopback path and converting to an electrical signal utilizing a photodetector, the photodetector being a replica of a photodetector in the main Rx path, and assessing the performance of the Tx and Rx paths by extracting a PRBS signal from the electrical signal. The transceiver may be a single complementary-metal oxide semiconductor (CMOS) die or in two CMOS die, where a first comprises electronic devices and a second comprises optical devices.
    Type: Grant
    Filed: April 25, 2018
    Date of Patent: July 9, 2019
    Assignee: Luxtera, Inc.
    Inventors: Steffen Gloeckner, Subal Sahni, Joseph Balardeta, Simon Pang, Stefan Barabas, Scott Denton
  • Patent number: 10312866
    Abstract: Methods and systems for process and temperature compensation in a transimpedance amplifier using a dual replica and servo loop is disclosed and may include a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, a third TIA, and a control loop. The first TIA comprises a fixed feedback resistance and the second and third TIAs each comprise a configurable feedback impedance. The control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and with an output coupled to the configurable feedback impedance of the second and third TIAs. The circuit may be operable to configure a gain level of the first TIA based on the fixed feedback resistance and a reference current applied at an input to the first TIA, and configure a gain level of the second and third TIAs based on a control voltage generated by the gain stage.
    Type: Grant
    Filed: January 18, 2016
    Date of Patent: June 4, 2019
    Assignee: Luxtera, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20190109572
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Application
    Filed: November 21, 2018
    Publication date: April 11, 2019
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Patent number: 10141904
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Grant
    Filed: September 18, 2017
    Date of Patent: November 27, 2018
    Assignee: Luxtera, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20180241517
    Abstract: Methods and systems for an optoelectronic built-in self-test (BIST) system for silicon photonics optical transceivers are disclosed and may include, in an optoelectronic transceiver having a transmit (Tx) path and a receive (Rx) path, where the Rx path includes a main Rx path and a BIST loopback path: generating a pseudo-random bit sequence (PRBS) signal, generating an optical signal in the Tx path by applying the PRBS signal to a modulator, communicating the optical signal to the BIST loopback path and converting to an electrical signal utilizing a photodetector, the photodetector being a replica of a photodetector in the main Rx path, and assessing the performance of the Tx and Rx paths by extracting a PRBS signal from the electrical signal. The transceiver may be a single complementary-metal oxide semiconductor (CMOS) die or in two CMOS die, where a first comprises electronic devices and a second comprises optical devices.
    Type: Application
    Filed: April 25, 2018
    Publication date: August 23, 2018
    Inventors: Steffen Gloeckner, Subal Sahni, Joseph Balardeta, Simon Pang, Stefan Barabas, Scott Denton
  • Publication number: 20180026597
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Application
    Filed: September 18, 2017
    Publication date: January 25, 2018
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Patent number: 9768747
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Grant
    Filed: January 18, 2016
    Date of Patent: September 19, 2017
    Assignee: Luxtera, Inc.
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20160211807
    Abstract: Methods and systems for process and temperature compensation in a transimpedance amplifier using a dual replica and servo loop is disclosed and may include a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, a third TIA, and a control loop. The first TIA comprises a fixed feedback resistance and the second and third TIAs each comprise a configurable feedback impedance. The control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and with an output coupled to the configurable feedback impedance of the second and third TIAs. The circuit may be operable to configure a gain level of the first TIA based on the fixed feedback resistance and a reference current applied at an input to the first TIA, and configure a gain level of the second and third TIAs based on a control voltage generated by the gain stage.
    Type: Application
    Filed: January 18, 2016
    Publication date: July 21, 2016
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton
  • Publication number: 20160211818
    Abstract: Methods and systems for accurate gain adjustment of a transimpedance amplifier using a dual replica and servo loop is disclosed and may include, in a transimpedance amplifier (TIA) circuit comprising a first TIA, a second TIA, and a third TIA, each comprising a configurable feedback impedance, and a control loop, where the control loop comprises a gain stage with inputs coupled to outputs of the first and second TIAs and an output coupled to the configurable feedback impedance of the second and third TIAs: configuring a gain level of the first TIA by configuring its feedback impedance, configuring a gain level of the third TIA by configuring a reference current applied to an input of the first TIA, and amplifying a received electrical signal to generate an output voltage utilizing the third TIA. The reference current may generate a reference voltage at one of the inputs of the gain stage.
    Type: Application
    Filed: January 18, 2016
    Publication date: July 21, 2016
    Inventors: Stefan Barabas, Joseph Balardeta, Simon Pang, Scott Denton