A control device connected to an inertial sensor having temperature characteristics, the control device including a memory for storing temperature compensation information, and update history information, an update determination circuit for determining the necessity of a temperature compensation information update based on a signal that is based on an output signal of a temperature sensor and the update history information, a rest determination circuit for determining whether the inertial sensor is at rest, and an updating circuit for updating the temperature compensation information based on the determination of the update determination circuit, the determination of the rest determination circuit, a signal based on an output signal of the inertial sensor, and the signal based on the output signal of the temperature sensor.

A physical quantity sensor includes an acceleration sensor having an acceleration sensor element and a package accommodating the acceleration sensor element, a support member having a first surface and supporting the acceleration sensor on the first surface, and an IC chip to which a second surface facing the first surface of the support member is attached, in which, in a plan view from a stacking direction of the acceleration sensor and the support member, in a case where an area of a region surrounded by an outer edge of the package is S1 and an area of the first surface is S2, S1S2 is satisfied.

A semiconductor device according to the present invention includes plural temperature sensors; a switching circuit that switches between detection signals from the temperature sensors at a predetermined frequency; an ADC that receives the output of the switching circuit and outputs a converted signal; a correction information extracting circuit that generates a temperature mean value; and an abnormality information extracting circuit that generates a temperature difference value.

An inertial measurement unit includes a sensor and a heat preservation system. The heat preservation system includes a heat preservation body and a heat source. The sensor is positioned on the heat preservation body. The heat source is configured to generate heat. The heat preservation body is configured to transfer the heat from the heat source to the sensor to maintain a preset temperature in a space surrounding the sensor.

An apparatus for measuring gravity acceleration of a drilling tool comprises sensors and a measurement circuit. The sensor comprises a three-axis gravity accelerometer, a reference measurement sensor and a temperature sensor. The three-axis gravity accelerometer measures acceleration component signals in three mutually orthogonal directions, and the reference measurement sensor generates a signal that varies with rotation and is not affected by vibration or shock to serve as a reference signal. The temperature sensor measures the temperature in the apparatus to compensate the temperature effect of the gravity accelerometers. The measurement circuit acquires output signals of the sensors and performs cross-correlation processing on the accelerometer components using the reference signal to extract gravity acceleration signals so as to eliminate centrifugal acceleration, vibration, shock and other interferences generated by rotation. The non-interference gravity acceleration signals is used for calculating an inclination angle and a toolface angle of a drilling tool in the rotating state.

An example transducer includes an upper magnetic circuit assembly including an upper excitation ring, a lower magnetic circuit assembly including a lower excitation ring, and a proof mass assembly positioned between the upper and lower magnetic circuit assemblies. A coefficient of thermal expansion (CTE) of the proof mass assembly is lower than a CTE of each of the upper and lower excitation rings. The transduces also includes an outer support structure coupled to an outer surface of each of the upper and lower excitation rings, and the outer support structure includes at least one cutout configured to reduce a circumferential stiffness of the outer support structure.

A Micro-Electrical-Mechanical-Systems (MEMS) accelerometer system includes a proof-mass device having a proof-mass that moves from an initial position in response to an input acceleration, a transducer connected to the proof-mass device to output a transducer signal correlating to movement and/or position of the proof-mass, and a driver configured to drive the proof-mass. A controller actively controls the driver to actively drive the proof-mass toward an initial position, and actively adjusts the drive signal based on a temperature signal (T) indicative of given temperature, a transducer voltage signal (Vref) indicative of a transducer voltage reference, and the transducer signal to actively generate a corrected drive signal and delivers the corrected drive signal to the driver to actively control the driver. The controller can also utilize a robust loop-shaping stabilization operation to produce both an unfiltered estimate of the input acceleration and an uncorrected drive signal to stabilize the proof mass.

Applying positive and negative feedback voltages to an electromechanical sensor of a microphone utilizing a voltage-to-voltage converter to facilitate an improvement in sensitivity and reduction in distortion of the microphone is presented herein. A microphone comprises an electromechanical sensor comprising a capacitive sense element comprising a first sense node and a second sense node; and a voltage-to-voltage converter comprising an input, a first output, and a second output. The voltage-to-voltage converter forms, via a first capacitive coupling to the second sense node, a negative feedback loop between the first output of the voltage-to-voltage converter and the input of the voltage-to-voltage converter. The first sense node is electrically coupled to the input of the voltage-to-voltage converter, and the voltage-to-voltage converter forms, via a second capacitive coupling to the first sense node, a positive feedback loop between the second output of the voltage-to-voltage converter and the input of the voltage-to-voltage converter.

An inertial sensor module includes: a first inertial sensor having a first axis as a detection axis; and a second inertial sensor having the first axis as a detection axis, in which detection accuracy of the first inertial sensor is higher than detection accuracy of the second inertial sensor, and the operation circuit receives a detection signal of the first axis output from the first inertial sensor and a detection signal of the first axis output from the second inertial sensor, and selects and outputs either a first output signal based on the detection signal of the first axis output from the first inertial sensor or a second output signal based on the detection signal of the first axis output from the second inertial sensor.

Conductive cooled gimbaled inertial measurement units are disclosed herein. An example apparatus includes an inertial measurement unit, a gimbal assembly in which the inertial measurement unit is disposed, the gimbal assembly having gaps between each gimbal of the gimbal assembly, the gaps including a gas to conduct heat from the gimbal assembly, and an isothermal dome at least partially surrounding the gimbal assembly, the isothermal dome having a cooling tube disposed on an external surface of the isothermal dome to transfer heat from the gimbal assembly via conduction.