Patents Assigned to Analog Devices, Inc.
  • Apparatus and method for providing linear transconductance amplification
    Patent number: 8174318
    Abstract: Apparatus and methods are disclosed, such as those involving a transconductance amplifier. One such apparatus includes a transconductance amplifier comprising an input to receive an input voltage signal, and an output to provide an output current signal at least partly in response to the input voltage signal. The apparatus also includes a linearizer configured to remove non-linearity in the output current signal such that the output current signal is substantially linear when the input voltage signal is within a range; and a current booster configured to add a current to the output current signal such that the output current signal is substantially linear when the input voltage signal is outside the range. The current booster allows the amplifier to have a linear response to a larger voltage swing without adding noise.
    Type: Grant
    Filed: July 12, 2010
    Date of Patent: May 8, 2012
    Assignee: Analog Devices, Inc.
    Inventor: Edmund Balboni
  • Vertical mount package for MEMS sensors
    Patent number: 8174111
    Abstract: A vertical mount pre-molded type package for use with a MEMS sensor may be formed with a low moisture permeable molding material that surrounds a portion of the leadframes and forms a cavity in which one or multiple dies may be held. The package includes structures to reduce package vibration, reduce die stress, increase vertical mount stability, and improve solder joint reliability. The vertical mount package includes a first leadframe having first leads and molding material substantially surrounding at least a portion of the first leads. The molding material forms a cavity for holding the MEMS sensor and forms a package mounting plane for mounting the package on a base. The cavity has a die mounting plane that is substantially non-parallel to the package mounting plane. The first leads are configured to provide electrical contacts within the cavity and to provide electrical contacts to the base.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: May 8, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Xiaojie Xue, Carl Raleigh, Thomas M. Goida
  • Apparatus and method for miller compensation for multi-stage amplifier
    Patent number: 8174321
    Abstract: An amplifier circuit includes a first amplifier stage having a first output node; a second amplifier stage having a second output node; and a compensation block electrically coupled between the first and second output nodes. The compensation block has a compensation capacitor electrically coupled to the first node and electrically connectable to the second node, and has an impedance electrically connectable to the compensation capacitor. The compensation capacitor is electrically coupled via a switch to the impedance such that the compensation capacitor can contribute a zero to shunt branch formed by the compensation capacitor and impedance when the compensation capacitor is disconnected from the second node.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: May 8, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Evgueni Ivanov, Arthur Kalb
  • Integrated microphone
    Patent number: 8169042
    Abstract: A method of forming a microphone having a variable capacitance first deposits high temperature deposition material on a die. The high temperature material ultimately forms structure that contributes to the variable capacitance. The method then forms circuitry on the die after depositing the deposition material. The circuitry is configured to detect the variable capacitance.
    Type: Grant
    Filed: July 28, 2010
    Date of Patent: May 1, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Jason W. Weigold, John R. Martin, Timothy J. Brosnihan
  • Charge injection discharge circuit
    Patent number: 8169193
    Abstract: A circuit for dissipating injected parasitic charge includes a circuit stage, a pulse generating circuit and a switch. The circuit stage has an input node and an output node that injects a parasitic charge when switched OFF to the output node. The pulse generating circuit can generate a pulsed signal having an input for receiving a control signal. The control signal indicates the circuit stage is switching OFF, and has an output for outputting a pulsed signal in response to the control signal at the input. The pulsed signal can have a predetermined duration. The switch can be configured to be actuated by the pulsed signal output by the pulse generating circuit, and has a terminal connected to the output node of the circuit stage and a terminal connected to circuit to substantially dissipate the injected parasitic charge.
    Type: Grant
    Filed: April 9, 2008
    Date of Patent: May 1, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Padraig Liam Fitzgerald, Nigel James Hayes
  • DEVICE WITH SEMICONDUCTOR DIE ATTACHED TO A LEADFRAME
    Publication number: 20120098113
    Abstract: Methods and resulting devices are disclosed related to attaching a die to a leadframe. One such method includes initially bonding a carrier pad which is pre-coated with a thermosetting first adhesive to the leadframe. The carrier pad can be electrically non-conductive. The first adhesive can be raised to its thermosetting cure temperature by heating the leadframe to a temperature just above the thermosetting cure temperature of the first adhesive. A thermosetting second adhesive which is liquid at room temperature can be applied to a second major surface of the carrier pad, and the die can be placed on the second adhesive and aligned with the leadframe. The second adhesive can be raised to its thermosetting cure temperature to bond the die to the carrier pad, and in turn form a bonded assembly.
    Type: Application
    Filed: January 5, 2012
    Publication date: April 26, 2012
    Applicant: Analog Devices, Inc.
    Inventor: Garrett Griffin
  • Signal dependent compensation with matched detectors
    Patent number: 8164377
    Abstract: A detector circuit includes a main path having a first detector to generate an output signal in response to an input signal, and a reference path having a second detector matched to the first detector to generate a reference signal in response to the input signal. The reference signal may be used to compensate the output signal for variations in operating frequency, temperature, or the like. The reference path may be arranged to reuse a signal available in the main path so that the signal applied to the second detector experiences the same operating effects as that applied to the first detector.
    Type: Grant
    Filed: February 14, 2006
    Date of Patent: April 24, 2012
    Assignee: Analog Devices, Inc.
    Inventor: Vincenzo DiTommaso
  • Temperature-compensation networks
    Patent number: 8159448
    Abstract: Temperature-compensation network embodiments are provided to generate compensation signals which may be useful in improving the performance of a variety of important systems. An embodiment includes a limit current mirror configured to provide a limit current, a current generator to provide a slope current whose magnitude varies with temperature, and an output current mirror positioned to receive the limit current and the slope current and configured to provide a compensation current. In addition, a floating voltage reference is provided for use in various networks which include the temperature-compensation networks. The temperature-compensation networks may be used to improve performance in systems such as a panel driver which provides turn-on and turn-off gate voltages to transistors in liquid crystal displays.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: April 17, 2012
    Assignee: Analog Devices, Inc.
    Inventor: Jeffrey G. Barrow
  • Voltage reference circuit based on 3-transistor bandgap cell
    Patent number: 8159206
    Abstract: A voltage regulator comprises first and second bipolar transistors operating at different current densities; a resistance is connected between their bases across which ?VBE appears. A third bipolar transistor is connected such that its base voltage is equal to that of the first transistor or differs by a PTAT amount. A current mirror balances the collector current of one of the second and third transistors with an image of the collector current of the first transistor when an output node is at a unique operating point. The operating point includes both PTAT and CTAT components, the ratio of which can be established to provide a desired temperature characteristic. A feedback transistor provides current to the bases of the bipolar transistors and to the output node and is driven by the current mirror output to regulate the voltage at the output node by negative feedback.
    Type: Grant
    Filed: November 24, 2008
    Date of Patent: April 17, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Hio Leong Chao, A. Paul Brokaw
  • INSTRUMENTATION INPUT SYSTEMS
    Publication number: 20120086513
    Abstract: An input stage for an instrumentation system may include a resistor coupled between an input terminal and a summing node, and an amplifier arranged to maintain the voltage at the summing node. In anther embodiment, an instrumentation input system may include an input stage to receive a signal to be measured, and a variable gain amplifier having an input coupled to an output of the input stage, wherein the variable gain amplifier comprises two or more gain stages. A variable gain amplifier may include an attenuator having an input and a series of tap points and a series of low-inertia switches to steer outputs from the attenuator to an output terminal.
    Type: Application
    Filed: December 19, 2011
    Publication date: April 12, 2012
    Applicant: Analog Devices, Inc.
    Inventor: Barrie Gilbert
  • Apparatus and method for HDMI transmission
    Patent number: 8154322
    Abstract: Apparatus and methods are disclosed, such as those involving a high frequency transmitter. One such apparatus includes a pre-amplifier configured to receive an input signal via an input node; and a capacitor block electrically coupled between the pre-amplifier and an output node from which an output signal is transmitted. The capacitor block is configured to provide charge to the output node or pull charge from the output node while the output signal transitions. The apparatus further includes a switch electrically coupled between the output node and a voltage reference, wherein the switch is turned on or off at least partly in response to a signal from the pre-amplifier. This configuration effectively reduces rise and fall time of the output signal for high-frequency transmission.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: April 10, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Barry Stakely, Gan Guo, Jiefeng Yan
  • Linearity correction circuit for voltage mode DAC
    Patent number: 8154433
    Abstract: A force/sense voltage-mode DAC coupled with multiple transconductance amplifiers that generate a correction current injected to a node in one of the DAC cells is discussed. The correction current injected into the DAC cell may reduce nonlinearity produced by biasing current to the operational amplifiers in the DAC.
    Type: Grant
    Filed: October 7, 2010
    Date of Patent: April 10, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Roderick McLachlan, Teng-Hee Lee
  • Digital output sensor FIFO buffer with single port memory
    Patent number: 8156264
    Abstract: A digital output sensor includes a sensor module for providing digital data representative of a sensed parameter, a First-In-First-Out (FIFO) memory having a single port memory, and an output port for transmitting the digital data. The digital data from the sensor module is pushed into the FIFO memory buffer via the single memory port, and the digital data is popped out of the FIFO memory buffer via the single memory port for receipt by the output port.
    Type: Grant
    Filed: April 3, 2009
    Date of Patent: April 10, 2012
    Assignee: Analog Devices, Inc.
    Inventor: James M. Lee
  • MEMS switching device protection
    Patent number: 8154365
    Abstract: A micro-machined switching system for equalizing an electrical property, such as charge due to parasitic capacitance formed at an input and an output of a micro-machined switching device. The micro-machined switching device may be a MEMS relay or a MEMS switch. In addition to the micro-machined switching device, the switching system also includes a balancing module for equalizing the electrical property between the input and the output of the micro-machined switching device. In certain embodiments, the balancing module includes a switch operable in a first state causing charge due to the parasitic capacitance on the input and the output of the micro-machined switching device to substantially balance. The switch is also operable in a second state wherein parasitic capacitance can separately accumulate at the input and the output of the micro-machined switching device.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: April 10, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Cammen Chan, Geoffrey T. Haigh
  • Mode-matching apparatus and method for micromachined inertial sensors
    Patent number: 8151641
    Abstract: A mode matching servo for an inertial sensor having a resonator and an accelerometer provides a test signal at a frequency higher than a predetermined inertial sensor response frequency and lower than an accelerometer resonance mode frequency so as to induce acceleration signals from the accelerometer substantially at the test signal frequency when the modes are not matched. A feedback signal is provided in response to such induced signals to substantially nullify the signals.
    Type: Grant
    Filed: May 21, 2009
    Date of Patent: April 10, 2012
    Assignee: Analog Devices, Inc.
    Inventor: John A. Geen
  • Apparatus for testing infrared sensors
    Patent number: 8147129
    Abstract: An apparatus for use with automatic testing equipment for testing infrared sensors on integrated circuits is provided. The apparatus includes an infrared source, a heat mass, and an electronic frequency modulator. The infrared source is modulated according to a predetermined test frequency such that the infrared source emits an infrared test signal representative of a test temperature and corresponding to the temperature of the heat mass and the predetermined test frequency. A signal processor, electrically coupled to an integrated circuit having an infrared sensor, receives a sensed signal from the infrared sensor in response to the infrared test signal and uses the sensed signal according to the predetermined test frequency to determine a measured temperature.
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: April 3, 2012
    Assignee: Analog Devices, Inc.
    Inventors: John Grubb, Gerard Blaney, Eamon Culhane
  • MEMS sensor with movable z-axis sensing element
    Patent number: 8146425
    Abstract: A MEMS sensor includes a substrate and a MEMS structure coupled to the substrate. The MEMS structure has a mass movable with respect to the substrate. The MEMS sensor also includes a reference structure positioned radially outward from the MEMS structure. The reference structure is used to provide a reference to offset any environmental changes that may affect the MEMS sensor in order to increase the accuracy of its measurement.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: April 3, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Xin Zhang, Michael W. Judy
  • Method and device for dividing a frequency signal
    Patent number: 8149028
    Abstract: A method for dividing a frequency includes the steps of receiving a first signal having a first frequency as a clock input to a first digital counter and outputting a second signal as a clock input to a second digital counter having a higher counting capacity than the first counter. The output occurs when the first counter reaches a first number of count cycles. The method also includes generating a third signal having a high cycle and a low cycle, which are determined at least as a function of the first number of count cycles. Depending on a desired division ratio, the high and low cycles may also be a function of a second number of count cycles associated with the second counter. The third signal has a frequency lower than the first frequency.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: April 3, 2012
    Assignee: Analog Devices, Inc.
    Inventors: John Kevin Behel, Reuben Pascal Nelson
  • Light-emitting diode backlighting systems
    Patent number: 8143792
    Abstract: Lighting system embodiments are provided to energize and calibrate strings of light-emitting diodes. These embodiments are particularly useful for calibration of strings of light-emitting diodes that are arranged to provide backlighting of liquid crystal displays. The systems are structured around the use of a single comparator that is multiplexed to facilitate calibration of a plurality of current sources. The systems can be adapted for use in displays in which different techniques (e.g., “analog dimming” and “pulse-width modulation”) are used to vary the brightness of the display. The systems remove the need for special structures (e.g., fuse arrays, special test equipment, and interfaces).
    Type: Grant
    Filed: August 19, 2009
    Date of Patent: March 27, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Chulmin Joo, Hyunick Shin
  • Packaged microchip with spacer for mitigating electrical leakage between components
    Patent number: 8138593
    Abstract: A packaged microchip has a base, at least one spacer coupled to the base, and first and second microchips mounted to the at least one spacer. The at least one spacer is configured to substantially prevent leakage current between the first and second microchips.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: March 20, 2012
    Assignee: Analog Devices, Inc.
    Inventors: Angelo Pagkaliwangan, Garry Griffin