1159 results about "Wheatstone bridge" patented technology

A system for protecting an electronic device from mechanical intrusion attempt. An intrusion barrier able to detect mechanical intrusion by means of circuit traces which detect any change in the resistance characteristics of the electric circuit. These circuit traces function as a resistors and they are connected together to form a Wheatstone bridge. According to the present invention the logical lay-out of these connections is selected so that the voltage difference between two adjacent traces is minimized. In this way the current leakage effect is limited to the minimum.

A combined pressure and temperature transducer (10) particularly adapted for high temperature fluids has a sensing element assembly mounted at the tip of a tubular probe (20) which is arranged for placement in a fluid flow path. A sensing element (12) includes a pressure responsive diaphragm (12g) closing the open end of the tubular probe and being provided with piezo-resistive gauge elements bonded to the diaphragm. Wires are bonded between the gauge elements and a first, heat resistant, printed circuit board (PCB). The first PCB, together with the piezo-resistive elements, form a Wheatstone bridge. An inner connector (26) mounts elongated, axial stress absorbing contacts connecting the first PCB at one end of the inner connector with a second printed circuit board (PCB) mounted at the opposite end of the inner connector physically removed from the sensing element and first PCB and away from the fluid flow path. The second PCB mounts signal conditioning and amplifying electronics. An outer connector (38) and housing (42) mounts the second PCB and provides an electrical interface with transducer.

An alternating current light-emitting device includes a substrate, a plurality of microdie light-emitting elements formed on the substrate, a rectifying element-dedicated member formed on a surface of a portion of microdie light-emitting elements, a rectifying unit formed on the rectifying element-dedicated member and provided with at least four rectifying elements forming a Wheatstone bridge circuit, and an electrically conductive structure electrically connecting the rectifying elements and the microdie light-emitting elements. With the rectifying unit being formed on the rectifying element-dedicated member, the rectifying elements are highly tolerant of reverse bias and feature low starting forward bias. Also, the present invention provides a method for fabricating an alternating current light-emitting device.

A pressure sensor assembly comprised of a single and dual layer diaphragm with integrated force sensing flexure, such as a cantilever beam. Strain gages are positioned on the force sensing beam. The pressure forces the diaphragm to deflect. The deflection is constrained by the beam, which is compelled to bend. The bending induces strains in strain gages located on the beam. The strain gages are connected in a Wheatstone bridge configuration. When a voltage is applied to the bridge, the strain gages provide an electrical output signal proportional to the pressure. Composite diaphragm—beam pressure sensors convert pressure more efficiently and improve sensor performance.

This invention provides a sensor to measure physical and/or chemical properties of viscous fluids. The sensor is based on microfabricated piezoresistive cantilevers. Deflection of these cantilevers is read out using, e.g., a wheatstone bridge to amplify and convert the deflection into a voltage output. The cantilevers and/or tips attached thereto, can be chemically or physically modified using reagents specific to interact with analytes to be detected in the fluid. The cantilevers can be integrated in a microfluidic system for easy fluid handling and the ability to manage small quantities of fluids.

A bolt with a function of measuring strain, comprising a Wheatstone bridge circuit comprising a strain sensor and a dummy resistor, a translate circuit that amplifies a signal from the Wheatstone bridge circuit to convert the same into a digital signal, a transmitting circuit that transmits the digital signal outside the bolt, and a power circuit, by which electromagnetic wave energy received from outside the bolt is supplied as a power source for at least any one of the circuits.

A capacitive position sensor has a periodic array of electrodes which form capacitors between pairs of the electrodes. The location of a dielectric inhomogeneity in the vicinity of the sensor is determined by comparison of the relative change in the capacitance of the capacitors. The comparison may be carried out using a capacitive Wheatstone Bridge arrangement. The sensor configuration has the advantage that it is independent of the absolute value of the dielectric constant of the environment in which the sensor is located.

A magnetic sensor includes a magnet located proximate to a target comprising a plurality of teeth and a plurality of slots formed therebetween. An integrated circuit is generally located on one side of the magnet wherein the integrated circuit comprises a plurality of asymmetrically arranged magnetoresistive bridge components, wherein the integrated circuit and the magnet are configured into a sensor package, such that the plurality of asymmetrically arranged magnetoresistive bridge components enables a detection of at least one tooth among the plurality of target teeth.

A process of performing a medical test includes taking multi-spectral images of an area of interest of a patient. The patient can be a human being or an animal, and can be known to be healthy or known to have health issues or problems. A multi-spectral camera includes a long-infrared charge-coupled device, a mid-infrared detector array, and a control device that synchronizes operation of the charge-coupled device and the detector array. The mid-infrared detector array can include carbon nanotubes. The carbon nanotubes can be detector elements. For example, the carbon nanotubes can be tuned-bandgap carbon nanotubes. Each pixel of resolution of the detector array can include a balanced Wheatstone bridge circuit including one of the tuned-bandgap carbon nanotubes. Adjacent pixels of the detector array can be arranged for orthogonal polarization.

A silicon monolithic miniature intra-ocular pressure sensing probe utilizes pressure sensing piezoresistors attached to a silicon pressure sensing membrane which is directly exposed to the irrigating fluid used during an eye operation, for example. From a silicon fabrication point of view, this is a micro electromechanical (MEM) device and the integration of the piezoresistive pressure sensor directly into the cannula which is inserted into the eye is partially made possible by providing p++ etch stops to gain access for electrical connection to the piezoresistive elements arranged in a Wheatstone bridge configuration. The silicon sensing membrane forms a smooth surface to avoid turbulence and is close to the eye to minimize error.

The invention discloses a pressure sensor based on Si-Si direct bonding, comprising a silicon substrate (1) with a shallow groove (8); the silicon substrate (1) is provided with a single crystal silicon stress membrane (2); a silicon dioxide layer (3) is arranged between the silicon substrate (1) and the stress membrane (2); four P-type single crystal silicon piezoresistors (4) are arranged on the stress membrane (2); an insulating medium silicon dioxide layer (7) is arranged among the stress membrane (2) and the piezoresistors (4); and a Wheatstone bridge is formed among the piezoresistors (4) by utilizing concentrated boron doped silicon (9) and a golden lead (6). The pressure sensor adopts Si-Si direct bonding technology to form the stress membrane and the sealing cavity; the piezoresistors thereof adopt silicon dioxide as an insulating layer and the working temperature can be up to 300 DEG C; and the pressure sensor has firm structure and excellent performance and can meet the requirements on high-temperature pressure sensors in the fields of automobile, aerospace and the like. The invention also relates to a manufacturing method of the pressure sensor.

An alternating current (AC) light emitting assembly and an AC light emitting device are disclosed. The AC light emitting assembly includes a substrate; a rectifier unit comprising a plurality of rectifier components arranged in a Wheatstone Bridge, for rectifying an AC signal into a direct current (DC) signal, each of the rectifier components having a high breakdown voltage and a low forward voltage; a light emitting unit electrically connected to the rectifier unit and comprising a plurality of light emitting components formed on the substrate, for emitting light when receiving the DC signal outputted by the rectifier unit; and two conductive electrodes electrically connected to the rectifier unit for receiving and transmitting the AC signal to the rectifier unit. The AC light emitting device includes two stacked and electrically connected AC light emitting assemblies.

An AMR gear tooth rotation sensor and a method for utilizing it are disclosed. These facilitate easy manufacture of the device without sacrificing either high sensitivity or high signal output. This is achieved by forming individual sensing elements out of AMR stripes and then connecting four such sensing elements as a Wheatstone bridge. The latter is attached to a permanent magnet that provides a bias field whose value rises and falls as wheel teeth and valleys (respectively) move past the rotation sensor.

A mechanical quantity measuring apparatus is provided which can make highly precise measurements and is not easily affected by noise even when it is supplied an electricity through electromagnetic induction or microwaves. At least a strain sensor and an amplifier, an analog/digital converter, a rectification/detection/modulation-demodulation circuit, and a communication control circuit are formed in one and the same silicon substrate. Or, the silicon substrate is also formed at its surface with a dummy resistor which has its longitudinal direction set in a particular crystal orientation and which, together with the strain sensor, forms a Wheatstone bridge. With this arrangement, even when a current flowing through the sensor is reduced, measured data is prevented from being buried in noise, allowing the sensor to operate on a small power and to measure a mechanical quantity with high precision even when it is supplied electricity through electromagnetic induction or microwaves.

A semiconductor process integrates three bridge circuits, each include magnetoresistive sensors coupled as a Wheatstone bridge on a single chip to sense a magnetic field in three orthogonal directions. The process includes various deposition and etch steps forming the magnetoresistive sensors and a plurality of flux guides on one of the three bridge circuits for transferring a ''Z'' axis magnetic field onto sensors orientated in the XY plane.

The invention relates to an integrated coil-biased giant magnetoresistance magneto-dependent sensor. A traditional magneto-dependent sensor has a complex manufacturing process, low finished product rate of products and low sensing sensitivity. The integrated coil-biased giant magnetoresistance magneto-dependent sensor comprises a whetatone bridge consisting of four GMR (Giant Magnetoresistance) magneto-dependent resistors, an integrated soft magnetic material layer and an integrated bias coil, wherein the integrated soft magnetic material layer is of an annular structure; a pair of clearances is formed in the diameter direction of the integrated soft magnetic material layer; a pair of resistors at opposite positions on a whetatone bridge arm is placed in one clearance of the integrated soft magnetic material layer; another pair of resistors at the opposite positions on the whetatone bridge arm is placed in the other clearance of the integrated soft magnetic material layer; and the width of the pair of clearances is consistent. The integrated bias coil is encircled on the integrated soft magnetic material layer. The integrated coil biased giant magnetoresistance magneto-dependent sensor has the advantages of small size of the sensor, high sensitivity and favorable linearity.

A non-invasive thermal dispersion flow meter with chronometric monitor for fluid leak detection includes a heater, an ambient temperature sensor and a flow rate sensor which are configured to sense the temperature of a fluid in a conduit, and then monitor the flow of that fluid through the conduit. The fluid flow sensor is incorporated into a Wheatstone bridge circuit which is used to provide increased sensitivity to the outputs of the sensors. Based upon the ambient temperature sensor readings, the flow rate sensor and heater may be adjusted to optimize the operation of the system to detect leaks. An alternative embodiment utilizes a single sensor and separate heater which work together to determine heat propagation times which in turn is used to calculate flow rate. Based on the sensor readings, the flow may be adjusted to prevent damage and leaks by relieving the system of excess pressure.

A pressure distribution detection device is characterized in that a flexible array sensor unit (2) is sequentially connected with a signal conditioning and data acquisition unit (3) and a data display and analysis unit (4); the flexible array sensor unit (2) consists of a sensor array (1) and a Wheatstone bridge circuit; the sensor array (1) consists of sensor nodes; each sensor node is a strain disc (6); the strain discs (6) are arranged to form the sensor array (1) in a line and row manner; and each strain disc (6) constitutes the Wheatstone bridge circuit with three precision resistors with known resistance values. When ambient pressure is applied on the strain discs (6), the resistors change, and the variation information of the resistance value of the flexible array sensor unit (2) is collected through the signal conditioning and data acquisition unit (3) and is transmitted to the data display and analysis unit (4) after analog-digital conversion to be displayed and analyzed. The invention is applicable to such fields as biomechanical engineering, medical rehabilitation and rehabilitation assistant property detection.

An integrated high-accuracy triaxial magnetic sensor comprises four magnetic measuring units, a signal-output and offset electrode, an inner plane accumulator, four magnetic orbital transfer accumulators, four pits and a basement. The inner plane accumulator adopts a symmetrical structure and is arranged in the middle of the basement, the four magnetic orbital transfer accumulators are arranged at four sides of the plane accumulator in a symmetrical mode, and each magnetic orbital transfer accumulator is arranged in a pit. Each magnetic measuring unit comprises a Wheatstone bridge formed by two giant magneto resistive (GMR) sensitive elements and two GMR reference elements. The integrated high-accuracy triaxial magnetic sensor has the advantages of being simple and compact, small in size, convenient to manufacture, low in manufacturing cost, and high in sensitivity and the like.

The present invention discloses a design and manufacturing method for a single-chip magnetic sensor bridge. The sensor bridge comprises four magnetoresistive elements. The magnetization of the pinned layer of each of the four magnetoresistive elements is set in the same direction, but the magnetization directions of the free layers of the magnetoresistive elements on adjacent arms of the bridge are set at different angles with respect to the pinned layer magnetization direction. The absolute values of the angles of the magnetization directions of the free layers of all four magnetoresistive elements are the same with respect with their pinning layers. The disclosed magnetic biasing scheme enables the integration of a push-pull Wheatstone bridge magnetic field sensor on a single chip with better performance, lower cost, and easier manufacturability than conventional magnetoresistive sensor designs.

The invention discloses an MEMS pressure sensor and a manufacturing method thereof. The MEMS pressure sensor comprises an MEMS pressure sensing chip, wherein the MEMS pressure sensing chip is arranged at a Wheatstone bridge formed on the crystallographic orientation of a monocrystalline silicon film (110) by four polycrystalline silicon resistors, the monocrystalline silicon film comprises a lower silicon wafer, an upper silicon wafer and a purification layer, a cavity body is arranged on the lower silicon wafer, the lower silicon wafer and the upper silicon wafer are bonded together by hot melt silicon-silicon, the surface of the upper silicon wafer is provided with a passivation layer, the polycrystalline silicon resistors are arranged on the upper silicon wafer by a diffusion process, and a conducting wire of a metal film and a press welding block are etched on the upper silicon wafer. The pressure sensor adopting a silicon-silicon bonding structure can be made in a very small size, the number of chips on each silicon wafer can be increased by 50% or more, the silicon-silicon bonding strength is higher, and the air tightness is better. The cost of the sensor is greatly lowered, and the performance is more stable and reliable. The sensor belongs to a pressure sensor with low cost and high performance and has very extensive application.

The invention discloses a sensor for 360-degree magnetic field angle measurement. It comprises multiple GMR (or MTJ) stripes with identical geometries except for their orientations. These are used as the building blocks for a pair of Wheatstone bridges that signal the direction of magnetization of their environment. The design greatly enhances sensitivity within GMR stripes and does not require an additional Hall sensor in order to cover the full 360 degree measurement range.