Patents Assigned to Luxtera
  • Patent number: 10763807
    Abstract: A system for a differential trans-impedance amplifier circuit comprising: an amplifier having a pair of input nodes and configured to generate an amplified replica of a differential voltage on said pair of input nodes; a photodiode; a pair of capacitors coupling said photodiode to said pair of input nodes; at least one resistance coupled between said pair of input nodes of said amplifier; and a bias network comprising two photodiode biasing resistances each photodiode biasing resistance coupled in series between said photodiode and a respective DC voltage. A feedback loop for the amplifier may include source followers that are operable to level shift voltages prior to coupling capacitors that couple said photodiode to said amplifier to ensure stable bias conditions for said amplifier. The source followers may include CMOS transistors. The amplifier may be integrated in a complementary metal-oxide semiconductor (CMOS) chip, which may include a CMOS photonics chip.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: September 1, 2020
    Assignee: LUXTERA LLC
    Inventor: Brian Welch
  • Patent number: 10749542
    Abstract: Systems and methods for an asynchronous successive approximation register analog-to-digital converter (SAR ADC) with word completion algorithm may include a SAR ADC comprising a plurality of switched capacitors, a comparator, a metastability detector including a timer having a tunable time interval, and a successive approximation register. The SAR ADC may sample input signals at inputs of the switched capacitors; compare signals at outputs of the switched capacitors, each for a respective bit; sense whether a metastability condition exists for the comparator using the timer and setting a metastability flag upon each metastability detection for each bit; increase a value of the tunable time interval if more than one metastability flag is set during conversion of a sampled input signal; decrease a value of the tunable time interval if no metastability flags are set; and use the flags for a word completion in the cases when not all the bits have been evaluated.
    Type: Grant
    Filed: June 28, 2019
    Date of Patent: August 18, 2020
    Assignee: Luxtera LLC.
    Inventor: Oleksiy Zabroda
  • Patent number: 10735100
    Abstract: Methods and systems for optical alignment to a silicon photonically-enabled integrated circuit may include aligning an optical assembly to a photonics die comprising a transceiver by, at least, communicating optical signals from the optical assembly into a plurality of grating couplers in the photonics die, communicating the one or more optical signals from the plurality of grating couplers to optical taps, with each tap having a first output coupled to the transceiver and a second output coupled to a corresponding output grating coupler, and monitoring an output optical signal communicated out of said photonic chip via said output grating couplers. The monitored output optical signal may be maximized by adjusting a position of the optical assembly. The optical assembly may include an optical source assembly comprising one or more lasers or the optical assembly may comprise a fiber array. Such a fiber array may include single mode optical fibers.
    Type: Grant
    Filed: July 23, 2019
    Date of Patent: August 4, 2020
    Assignee: Luxtera LLC.
    Inventors: Michael Mack, Anders Dahl, Subal Sahni, Steffen Gloeckner
  • Patent number: 10734090
    Abstract: Systems and methods for a track and hold amplifier with extended dynamic range may include a track amplifier comprising a first PMOS transistor coupled to a first NMOS transistor, a second PMOS transistor coupled to a second NMOS transistor, a capacitor at gates of each NMOS and PMOS transistor, and a plurality of switches. The track and hold amplifier is operable to, during a tracking mode of the track and hold amplifier, couple a differential input signal to each NMOS and PMOS transistor via a first switch coupled to a first capacitor coupled to the gate of the first PMOS transistor and a second capacitor coupled to the gate of the first NMOS transistor, and via a second switch coupled to a third capacitor coupled to the gate of the second PMOS and a fourth capacitor coupled to the gate of the second NMOS transistor.
    Type: Grant
    Filed: June 30, 2019
    Date of Patent: August 4, 2020
    Assignee: Luxtera LLC.
    Inventor: Oleksiy Zabroda
  • Patent number: 10727944
    Abstract: Methods and systems for optoelectronics transceivers of a CMOS chip are disclosed and may include receiving optical signals from optical fibers via grating couplers, which may include a guard ring. A CW optical signal may be received from a laser source via optical couplers, and may be modulated using optical modulators, which may be Mach-Zehnder and/or ring modulators. Circuitry in the CMOS chip may drive the optical modulators. The modulated optical signal may be communicated out of the CMOS chip into optical fibers via grating couplers. The received optical signals may be communicated between devices via waveguides. The photodetectors may include germanium waveguide photodiodes, avalanche photodiodes, and/or heterojunction diodes. The CW optical signal may be generated using an edge-emitting and/or a vertical-cavity surface emitting semiconductor laser.
    Type: Grant
    Filed: July 2, 2019
    Date of Patent: July 28, 2020
    Assignee: Luxtera LLC.
    Inventors: Thierry Pinguet, Steffen Gloeckner, Sherif Abdalla, Sina Mirsaidi, Peter De Dobbelaere, Lawrence C. Gunn, III
  • 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: 10712513
    Abstract: Methods and systems for two-dimensional mode-matching grating couplers may include in a photonic chip comprising a grating coupler at a surface of the photonic chip, where the grating coupler has increased scattering strength in a direction of a light wave traveling through the grating coupler: receiving an optical signal from a first direction within the photonic chip; and scattering the optical signal out of the surface of the photonic chip. A second optical signal may be received in the grating coupler from a second direction within the photonic chip. The second optical signal may be scattered out of the surface of the photonic chip. The increasing scattering strength may be caused by increased width scatterers along a direction perpendicular to the direction of light travel. The increased scattering strength may be caused by a transition of shapes of scatterers in the grating coupler.
    Type: Grant
    Filed: October 7, 2019
    Date of Patent: July 14, 2020
    Assignee: Luxtera, LLC
    Inventors: Roman Bruck, Attila Mekis
  • Patent number: 10686526
    Abstract: Methods and systems for silicon photonics wavelength division multiplexing transceivers are disclosed and may include, in a transceiver integrated in a silicon photonics chip: generating a first modulated output optical signal at a first wavelength utilizing a first electrical signal, generating a second modulated output optical signal at a second wavelength utilizing a second electrical signal, communicating the first and second modulated output optical signals into an optical fiber coupled to the chip utilizing a multiplexing grating coupler in the chip. A received input optical signal may be split into a modulated input optical signal at the first wavelength and a modulated input optical signal at the second wavelength utilizing a demultiplexing grating coupler in the chip. The first and second modulated input optical signals may be converted to first and second electrical input signals utilizing first and second photodetectors in the chip.
    Type: Grant
    Filed: March 14, 2019
    Date of Patent: June 16, 2020
    Assignee: Luxtera, Inc.
    Inventors: Attila Mekis, Peter De Dobbelaere, Lieven Verslegers, Peng Sun, Yannick De Koninck
  • Patent number: 10627575
    Abstract: Methods and systems for mode converters for grating couplers may include a photonic chip comprising a waveguide, a grating coupler, and a mode converter, with the waveguide being coupled to the grating coupler via the mode converter. The mode converter may include waveguide material and tapers defined by tapered regions, where the tapered regions do not have waveguide material. The photonic chip may receive an optical signal in the mode converter from the waveguide, where the received optical signal has a light profile that may be spatially deflected in the mode converter to configure a desired profile in the grating coupler. A long axis of the tapers may be parallel to a direction of travel of the optical signal. The long axis of the tapers may point towards the input waveguide of the grating couplers, which may be linear.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: April 21, 2020
    Assignee: Luxtera, Inc.
    Inventors: Roman Bruck, Attila Mekis
  • Patent number: 10623109
    Abstract: Methods and systems for a distributed optoelectronic receiver are disclosed and may include an optoelectronic receiver having a grating coupler, a splitter, a plurality of photodiodes, and a plurality of transimpedance amplifiers (TIAs). The receiver receives a modulated optical signal utilizing the grating coupler, splits the received signal into a plurality of optical signals, generates a plurality of electrical signals from the plurality of optical signals utilizing the plurality of photodiodes, communicates the plurality of electrical signals to the plurality of TIAs, amplifies the plurality of electrical signals utilizing the plurality of TIAs, and generates an output electrical signal from coupled outputs of the plurality of TIAs. Each TIA may be configured to amplify signals in a different frequency range. One of the plurality of electrical signals may be DC coupled to a low frequency TIA of the plurality of TIAs.
    Type: Grant
    Filed: March 15, 2019
    Date of Patent: April 14, 2020
    Assignee: Luxtera, Inc.
    Inventors: Brian Welch, Gianlorenzo Masini
  • 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
  • Patent number: 10613281
    Abstract: Methods and systems for coupling a light source assembly to an optical integrated circuit are disclosed and may include a system comprising a laser source assembly having a laser, a rotator, and a mirror, where the laser source assembly is coupled to a die including an angled grating coupler and a waveguide. The system may generate an optical signal utilizing the laser, rotate the polarization of the optical signal utilizing the rotator, reflect the rotated optical signal onto the grating coupler on the die, and couple the optical signal to the waveguide, where an angle between a grating coupler axis that is parallel to the waveguide and a plane of incidence of the optical signal reflected to the angled grating coupler is non-zero. The angle between the grating coupler axis and the plane of incidence of the optical signal reflected to the angled grating coupler may be 45 degrees.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventors: Attila Mekis, Peng Sun, Steffen Gloeckner, Michael Mack, Steven Hovey
  • Patent number: 10615903
    Abstract: Methods and systems for a polarization immune wavelength division multiplexing demultiplexer are disclosed and may include, in an optoelectronic transceiver having an input coupler, a demultiplexer, and an amplitude scrambler: receiving input optical signals via the input coupler, communicating the input optical signals to the amplitude scrambler via waveguides, configuring the average optical power in each of the waveguides utilizing the amplitude scrambler, and demultiplexing the optical signals utilizing the demultiplexer. The amplitude scrambler may include phase modulators and a coupling section. The phase modulators may include sections of P-N junctions in the two waveguides. The demultiplexer may include a Mach-Zehnder Interferometer. The demultiplexed signals may be received utilizing photodetectors. The input coupler may include a polarization splitting grating coupler.
    Type: Grant
    Filed: July 1, 2019
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventor: Brian Welch
  • Patent number: 10615900
    Abstract: A method and system is provided for cassette based wavelength division multiplexing and may include an optical system with an aggregating cassette. The optical system may include optical transceivers, with each generating optical signals at a different wavelength. The aggregating cassette may include one or more multiplexers coupled to each of the optical transceivers via optical fibers. The optical transceivers may generate modulated optical signals at one of the different wavelengths. The optical fibers may communicate one of the modulated optical signals from each of the optical transceivers to the one or more multiplexers. The modulated optical signals may be multiplexed to one or more output optical fibers. The multiplexed signals may be communicated to one or more receiving demultiplexers using the one or more output optical fibers. The one or more demultiplexers may demultiplex the multiplexed signals into separate wavelength signals.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventor: Brian Welch
  • Patent number: 10613274
    Abstract: Methods and systems for integrated multi-port waveguide photodetectors are disclosed and may include an optical receiver on a chip, where the optical receiver comprises a multi-port waveguide photodetector having three or more input ports. The optical receiver may be operable to receive optical signals via one or more grating couplers, couple optical signals to the photodetector via optical waveguides in the chip, and generate an output electrical signal based on the coupled optical signals using the photodetector. The photodetector may include four ports coupled to two PSGCs. The optical signals may be coupled to the photodetector via S-bends and/or tapers at ends of the optical waveguides. A width of the photodetector on sides that are coupled to the optical waveguides may be wider than a width of the optical waveguides coupled to the sides. Optical signals may be mixed with local oscillator signals using the multi-port waveguide photodetector.
    Type: Grant
    Filed: May 11, 2017
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventors: Subal Sahni, Gianlorenzo Masini, Attila Mekis
  • Patent number: 10613358
    Abstract: Methods and systems for a low-voltage integrated silicon high-speed modulator may include an optical modulator comprising first and second optical waveguides and two optical phase shifters, where each of the two optical phase shifters may comprise a p-n junction with a horizontal section and a vertical section and an optical signal is communicated to the first optical waveguide. A portion of the optical signal may then be coupled to the second optical waveguide. A phase of at least one optical signal in the waveguides may be modulated utilizing the optical phase shifters. A portion of the phase modulated optical signals may be coupled between the two waveguides, thereby generating two output signals from the modulator. A modulating signal may be applied to the phase shifters which may include a reverse bias.
    Type: Grant
    Filed: August 7, 2018
    Date of Patent: April 7, 2020
    Assignee: Luxtera, Inc.
    Inventors: Ali Ayazi, Kam-Yan Hon, Gianlorenzo Masini
  • Patent number: 10606003
    Abstract: Methods and systems for an optical coupler for photonics devices are disclosed and may include a photonics transceiver comprising a silicon photonics die, an optical source module, and a fiber connector for receiving optical fibers and including a die coupler and an optical coupling element. The die coupler may be bonded to a top surface of the photonics die and aligned above an array of grating couplers. The optical coupling element may be attached to the die coupler and the electronics die and the source module may be bonded to the top surface of the photonics die. A continuous wave (CW) optical signal may be received in the photonics die from the optical source module. Modulated optical signals may be received in the photonics die from optical fibers coupled to the fiber connector.
    Type: Grant
    Filed: July 31, 2014
    Date of Patent: March 31, 2020
    Assignee: Luxtera, Inc.
    Inventors: Mark Peterson, Brian Welch, Steffen Gloeckner, Peter DeDobbelaere, Michael Mack
  • Patent number: 10608750
    Abstract: Methods and systems for a narrowband, non-linear optoelectronic receiver are disclosed and may include amplifying a received signal, limiting a bandwidth of the received signal, and restoring the signal utilizing a level restorer, which may include a non-return to zero (NRZ) level restorer. The NRZ level restorer may include a pulse-triggered bistable circuit, which may include two parallel inverters, with one being a feedback path for the other. The inverters may be single-ended or differential. A photogenerated signal may be amplified in the receiver utilizing a transimpedance amplifier and programmable gain amplifiers (PGAs). A received electrical signal may be amplified via PGAs. The bandwidth of the received signal may be limited utilizing one or more of: a low pass filter, a bandpass filter, a high pass filter, a differentiator, or a series capacitance on the chip. The signal may be received from a photodiode integrated on the chip.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: March 31, 2020
    Assignee: Luxtera, Inc.
    Inventor: John Andrew Guckenberger
  • Patent number: 10581526
    Abstract: Methods and systems for a bi-directional receiver for standard single-mode fiber based on grating couplers may include, in an integrated circuit, a multi-wavelength grating coupler, and first and second optical sources coupled to the integrated circuit: coupling first and second source optical signals at first and second wavelengths into the photonically-enabled integrated circuit using the first and second optical sources, where the second wavelength is different from the first wavelength, receiving a first optical data signal at the first wavelength from an optical fiber coupled to the multi-wavelength grating coupler, and receiving a second optical data signal at the second wavelength from the optical fiber. Third and fourth optical data signals at the first and second wavelengths may be communicated out of the optoelectronic transceiver via the multi-wavelength grating coupler.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: March 3, 2020
    Assignee: Luxtera, Inc.
    Inventors: Peter DeDobbelaere, Christopher Bergey, Attila Mekis
  • Patent number: 10578892
    Abstract: Methods and systems for a low-parasitic silicon high-speed phase modulator are disclosed and may include in an optical phase modulator that comprises a PN junction waveguide formed in a silicon layer, wherein the silicon layer may be on an oxide layer and the oxide layer may be on a silicon substrate. The PN junction waveguide may have fingers of p-doped and n-doped regions on opposite sides along a length of the PN junction waveguide. Contacts may be formed on the fingers of p-doped and n-doped regions. The fingers of p-doped and n-doped regions may be arranged symmetrically about the PN junction waveguide or staggered along the length of the PN junction waveguide. Etch transition features may be removed along the p-doped and n-doped regions.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: March 3, 2020
    Assignee: Luxtera, Inc.
    Inventors: Ali Ayazi, Gianlorenzo Masini, Subal Sahni, Attila Mekis, Thierry Pinguet