Gas Patents (Class 73/514.07)
  • Patent number: 9897460
    Abstract: The present invention concerns an MEMS sensor and a method for compensation of a quadrature error on an MEMS sensor, which is intended for detection of movements of a substrate, especially accelerations and/or rotation rates. At least one mass arranged on the substrate and mounted to move relative to it is driven by means of drive electrodes. The mass/es execute a movement deviating from the prescribed movement due to a quadrature error. A deflection of the mass/es occurring due to Coriolis force and quadrature error is detected with detection electrodes. It is proposed according to the invention that a capacitance change be detected as a function of drive movement of the mass/es by means of compensation electrodes. A compensation charge dependent on the quadrature error of the MEMS sensor is generated on the compensation electrodes. For compensation, the distorted or incorrect charge generated by the quadrature error in the detection electrodes is compensated with the compensation charge.
    Type: Grant
    Filed: June 8, 2015
    Date of Patent: February 20, 2018
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Luca Coronato, Gabrielle Cazzaniga, Carlo Caminada, Manuel Santoro, Luciano Prandi, Demetre Kondylis
  • Patent number: 7080553
    Abstract: A micro-accelerometer includes first and second closed cavities, into each of which an equal quantity of gas is introduced. A membrane partitions the symmetrical first and second cavities. Temperature sensors are provided within the first and second cavities, respectively, to measure the gas temperatures within the cavities. Difference of temperature is not caused so long as no acceleration affects the inner side of the cavities. However, if a linear acceleration is applied, the membrane is deformed in the direction of acceleration, whereby for example, the gas within the first temperature is compressed and its temperature increases, whereas the temperature of the second cavity decreases because the gas is expanded within the second cavity. The difference of gas temperatures between the first and second cavities is measured as a variation of electric power resistance by the temperature sensors and applied as a function of acceleration.
    Type: Grant
    Filed: January 5, 2005
    Date of Patent: July 25, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xiao-bing Luo, Hye-jung Cho
  • Patent number: 6674383
    Abstract: Methods and apparatus for varying and measuring the position of a micromachined electrostatic actuator using a pulse width modulated (PWM) pulse train are disclosed. One or more voltage pulses are applied to the actuator. In each of the pulses, a voltage changes from a first state to a second state and remains in the second state for a time tpulse before returning to the first state. The position of the actuator may be varied by varying the time &Dgr;tpulse. A position of the actuator may be determined by measuring a capacitance of the actuator when the voltage changes state, whether the time t is varied or not. An apparatus for varying the position of a MEMS device may include a pulse width modulation generator coupled to the MEMS device an integrator coupled to the MEMS device and an analog-to-digital converter coupled to the integrator. The integrator may measure a charge transferred during a transition of a pulse from the pulse generator.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: January 6, 2004
    Assignee: Onix Microsystems, Inc.
    Inventors: David Horsley, Robert Conant, William Clark