Class / Patent application number | Description | Number of patent applications / Date published |
324655000 | Including a tuned or resonant circuit | 43 |
20090261844 | INDUCTIVE DETECTOR - A low cost, high performance method and apparatus for identifying electrical intermediate devices and measuring their position relative to an antenna is provided. The technique preferably uses electrical intermediate devices co-operating with AC energized antennae. The resulting electrical data can be used in a wide variety of user interfaces, identification systems and sensors to measure, for example, rotary position, linear position, weight, level, torque, vibration, turbidity and flow. The invention includes means for the contactless transmission of data and power to general instrumentation. | 10-22-2009 |
20090267617 | APPARATUS AND METHOD FOR MEASURING SALINITY OF A FLUID BY INDUCTANCE - A salinity sensor for sensing or measuring salinity of a static or flowing fluid without contacting the fluid includes magnetic coil with a gapped core and a conduit for the fluid positioned in the gap in the core. The magnetic coil and the portion of the magnetic field produced by the coil that extends through the fluid in the gap are part of an LC or LCR circuit that can be driven to resonant frequency for a fluid of known salinity, which may include, but is not limited to, a fluid having zero salinity, as indicated by a peak output voltage on the circuit. Then, when the salinity of the fluid in the gap changes or a fluid with a different salinity is placed in the gap, the characteristics of the LC or LCR circuit, including inductance L and resonant frequency, change, and such changes can be detected and measured as an indication of the salinity of the fluid in the gap. | 10-29-2009 |
20090273353 | STRAIN MONITORING SYSTEM AND APPARATUS - This application relates to an apparatus and system for sensing strain on a portion of an implant positioned in a living being. In one aspect, the apparatus has at least one sensor assembly that can be mountable thereon a portion of the implant and that has a passive electrical resonant circuit that can be configured to be selectively electromagnetically coupled to an ex-vivo source of RF energy. Each sensor assembly, in response to the electromagnetic coupling, can be configured to generate an output signal characterized by a frequency that is dependent upon urged movement of a portion of the passive electrical resonant circuit and is indicative of strain applied thereon a portion of the respective sensor assembly. | 11-05-2009 |
20100134122 | Substrate, substrate holding apparatus, analysis apparatus, program, detection system, semiconductor device, display apparatus, and semiconductor manufacturing apparatus - A substrate including a sensor unit, wherein the sensor unit includes a coil wound at least once arranged on the surface of the sensor or embedded within and near the surface thereof. With such an arrangement, an electric current that corresponds to information with respect to the substrate flows through the coil. | 06-03-2010 |
20100141273 | SYSTEMS AND METHODS FOR USING FERRITE ALIGNMENT KEYS IN WIRELESS REMOTE SENSORS - The present invention related to devices and methods for using ferrite alignment keys in wireless remote sensor assemblies. In one aspect, the invention provides wireless resonant sensor assemblies comprising a pick-up coil, a ferrite alignment key positioned in and extending from the pick-up coil, and wireless resonant sensor having a receiving element wherein the pick-up coil and the wireless resonant sensor align upon insertion of the ferrite alignment key into the receiving element. The ferrite alignment key may also be part of a resonant sensor such that insertion of a pick-up coil into a receiving element of the alignment key results in a configuration where the alignment key is positioned in and extended from the pick-up coil. Methods of measuring one or more parameters of a monitoring system are also provided. The insertion of the ferrite alignment key aligns the pick-up coil and wireless resonant sensor thereby increasing sensing of the wireless resonant sensor by the pick-up coil. | 06-10-2010 |
20100148800 | INDUCTIVE SWITCH FOR ADJUSTMENT AND SWITCHING FOR APPLICATIONS IN SPECIAL ENVIRONMENTS - An inductive programming switch for applications in special environments, comprising an inductive component and a container in which the inductive component is accommodated proximate to a wall of the container, the inductive component being connected to an electronic evaluation circuit, which is adapted to detect variations of parameters of the inductive component caused by the approach of a metallic object to the wall, the evaluation circuit being adapted to detect and identify a sequence of approach/spacing of the metallic object with respect to the wall and for modifying its functional parameters according to the sequence. | 06-17-2010 |
20100201380 | Inductive sensor whose output is independent of the type of detectable metallic material - An inductive sensor which uses two resonant LC circuits, one of reference and the other for measurement. The measurement inductor is arranged close to the active surface of the sensor. The reference inductor is shielded so that it is influenced less or not at all by the metallic body, but can follow the variations caused by the environmental temperature on the measurement inductor. The two LC circuits are excited by way of distinct pulses, so as to produce similar dampened oscillations, which are slightly different in terms of amplitude and phase. The reference oscillation can be elaborated to obtain a reference amplitude at a precise instant or during a reading time window to observe the oscillation of the measurement inductor. | 08-12-2010 |
20100219841 | Conductivity Sensor - A conductivity sensor is disclosed. The conductivity sensor includes an oscillator for providing an input signal and a reactive circuit having an induction coil, a capacitive element, and a resistive element connected in parallel. The induction coil is adapted to be placed adjacent to a specimen. The conductivity sensor further includes a control circuit for driving the reactive circuit to resonance when the induction coil is placed adjacent to the specimen. The reactive coil is configured to provide an output signal having a parameter representative of the conductivity of the specimen when the reactive circuit is at resonance. The induction coil may include a first conductive element that spirals outward to an external perimeter and a second conductive element operably connected to the first conductive element. The second conductive element spirals inward from the external perimeter staggered relative to the first conductive element. | 09-02-2010 |
20100259282 | DETECTOR FOR PROXIMITY SENSOR AND PROXIMITY SENSOR - A detector for a proximity sensor, includes: a sensing portion including a pair of sensing coils which has central axes along a direction intersecting with a moving direction of a sensed object moving in a predetermined moving path and is provided so as to interpose the moving path; a circuit block including a capacitor composing an LC resonant circuit with the sensing coils of the sensing portion and provided with an oscillator which oscillates the LC resonant circuit; and an electric connector composed of first connection terminals and a first conductor pattern that connect the sensing coils of the sensing portion in series, and second connection terminals and a second conductor pattern that connect the sensing coils to the oscillator. | 10-14-2010 |
20110025349 | INDUCTIVE POSITION DETECTOR - An inductive detector arranged to measure position along a axis comprising: a transmit winding; a receive winding; a passive circuit comprising a winding in electrical series with a capacitor; wherein: the mutual inductance between the transmit winding and the receive winding is a function of the relative displacement of the passive circuit along the measurement axis; a first portion of one of the windings is wound on a first pitch and a second portion of the same winding is wound on a second pitch whose extent is greater than the first pitch. | 02-03-2011 |
20110057668 | INDUCTIVE PROXIMITY SENSOR - The present invention relates to an inductive proximity sensor that includes an oscillator having first and second inductor-capacitor circuits arranged such that an inductance of one of the inductor-capacitor circuits has substantially greater sensitivity to an external target than an inductance of the other inductor-capacitor circuit. The sensor also includes an alternating current drive to each of the inductor-capacitor circuits that is in-phase and depends on differences in voltage across the inductor-capacitor circuits. The sensor may be coupled to a calibration device that applies power and triggers a calibration routine within the sensor. In response to the trigger signal, a calibration processor within the sensor executes the calibration routine and adjusts the inductor-capacitor circuits and provides an indication of successful calibration. | 03-10-2011 |
20110101996 | METHOD AND SYSTEM FOR PERFORMANCE ENHANCEMENT OF RESONANT SENSORS - The present invention related to methods and systems for simultaneously sensing two or more environmental parameters of a sample. Included is an inductor-capacitor-resistor (LCR) resonator sensor and a pick up coil in operative association with the LCR resonator sensor wherein viscoelastic changes in the sensing film cause displacement of the antenna relative to the pick up coil. | 05-05-2011 |
20120074959 | COIN DETECTOR - A coin detector includes an oscillator circuit using an oscillator for generating a magnetizing signal of a predetermined oscillation frequency and an eddy current sensor for producing an AC magnetic field for sensing the variation of the inductance of an eddy current produced upon passing of a coin, a FM demodulator and an AM demodulator respectively electrically coupled to the oscillator circuit by a respective buffer for demodulating the voltage frequency and voltage amplitude of the oscillation signal outputted by the oscillator circuit, and a recognition logic unit for computing the demodulated FM signal outputted by the FM demodulator and the demodulated AM signal outputted by the AM demodulator by means of using time as a parameter to recognize the authenticity and value of the sensed coin. | 03-29-2012 |
20120081132 | Measuring Minority Carrier Lifetime - An apparatus includes a member including a ferromagnetic material, an inductance-capacitance resonant circuit, a substrate disposed relative to the member, and a plurality of radiation sources. The member includes a post disposed at its center and a surface extending to an outer wall. The member defines a gap between the post and the outer wall. The inductance-capacitance resonant circuit is configured to resonate at a measurement frequency. The circuit includes an inductor disposed relative to the post. The substrate is disposed relative to the member. The substrate is electromagnetically coupled to the inductor. The plurality of radiation sources is disposed radially outward from and circumferentially around the post of the member. The apparatus can be used to simultaneously measure conductance (inverse sheet resistance), steady state photoconductance, true steady state minority carrier lifetime, photoconductance build-up and photoconductance decay lifetime. | 04-05-2012 |
20120161789 | DEVICE FOR MONITORING AT LEAST A PHYSICAL CHARACTERISTIC OF A BUILDING MATERIAL - A monitoring device is for monitoring physical characteristics of a building material. The monitoring device is buried inside a block of the building material, and has a sensor to sense physical characteristics thereof. The sensor transmits a signal representative of the physical characteristics. | 06-28-2012 |
20120286806 | Measuring Bulk Lifetime - A substrate is electromagnetically coupled into an inductance-capacitance resonant circuit formed from (i) a member comprising a ferromagnetic material, (ii) an inductor and (iii) the substrate. The substrate is illuminated for a first time period X to cause photoconduction in the substrate. Decay in conductivity of the substrate is monitored for a second time period Y. The ratio of X to Y is greater than 1:10. Bulk lifetime of the substrate is determined from the decay. | 11-15-2012 |
20120286807 | ELECTRONIC CIRCUIT AND METHOD FOR DETERMINING AN IMPEDANCE - An electronic circuit is arranged in an external programming device and is used for contactless programming of a circuit to be programmed. The electronic circuit has a series resonant circuit that includes a transmitter coil and a capacitor. The transmitter coil of the series resonant circuit is used for inductive coupling to a receiver coil in the circuit to be programmed. For the purpose of evaluating the impedance that actually exists in the circuit to be programmed, there is provided a device for determining the value of the impedance from a phase difference between the control voltage of the series resonant circuit and the capacitor voltage of the series resonant circuit. | 11-15-2012 |
20120293188 | APPARATUS AND METHOD OF USING IMPEDANCE RESONANCE SENSOR FOR THICKNESS MEASUREMENT - An apparatus for, and methods of use for, measuring film thickness on an underlying body are provided. The apparatus may include at least one Impedance Resonance (IR) sensor, which may include at least one sensing head. The at least one sensing head may include an inductor having at least one excitation coil and at least one sensing coil. The excitation coil may propagate energy to the sensing coil so that the sensing coil may generate a probing electromagnetic field. The apparatus may also include at least one power supply, at least one RF sweep generator electrically connected to the excitation coil; at least one data acquisition block electrically connected to the sensing coil; at least one calculation block; and at least one communication block. Methods of monitoring conductive, semiconductive or non-conductive film thickness, and various tools for Chemical Mechanical Polishing/Planarization (CMP), etching, deposition and stand-alone metrology are also provided. | 11-22-2012 |
20130021043 | POSITION SENSOR - A position sensor includes a detector, an oscillation circuit, a signal processing circuit, and a resonance circuit having a detection coil and a capacitor. The oscillation circuit forms a negative feedback loop from: an amplitude detection circuit that detects an amplitude of an oscillation signal outputted from the resonance circuit; an integrating circuit that outputs a signal corresponding to a difference between a predetermined reference voltage and the amplitude of the oscillation signal; a negative conductance control circuit that, based on the output of the integrating circuit, controls the negative conductance of the oscillation circuit such that the amplitude of the oscillation signal is equals to the predetermined reference voltage; and an operational amplifier that adjusts such that the oscillation voltage of the resonance circuit is equal to the applied voltage of the negative conductance control circuit. | 01-24-2013 |
20130043888 | WIRELESS METHOD AND APPARATUS FOR DETECTING DAMAGE IN CERAMIC BODY ARMOR - A wireless damage detector for ceramic armor plates includes an interrogator and a body armor ceramic plate. The interrogator includes an inductive primary coil having a resonant frequency. The plate includes a corresponding inductive secondary coil adapted to cooperate with the primary coil when the interrogator is positioned in an interrogation position wirelessly adjacent the plate. When in the interrogation position, the primary and secondary coils are inductively coupled, that is, form an inductive coupling, when the primary coil is energized at the resonant frequency. The plate includes at least one self-contained frangible continuity circuit electrically connected to the secondary coil. The inductive coupling induces an electrical current flow in the continuity circuit when the circuit is undamaged. A detector cooperates with the primary and secondary coils when the interrogator is in the interrogation position. The detector detects the inductive coupling. An indicator cooperates with the detector. | 02-21-2013 |
20130088243 | POSITION SENSING HEAD WITH REDUNDANCY - A position sensing head combines a sensing element and a simplified electronic module to enable operation with one wire, in addition to a circuit common, for providing power and transmitting a signal, while separating the sensing head from signal conditioning circuits by over 10 meters. The simplicity of the electronic module allows the use of basic electronic components that operate at more than 225° C. The signal is a variable frequency impressed onto the one wire, which can be read by a frequency meter. Another signal, such as a position or temperature, can be impressed onto the one wire at the same time as the first signal. The second signal is of a different frequency range so that it will not interfere with the first. A demodulator circuit can separate the two signals. The sensing element construction allows for locating up to three active elements measuring the same target. | 04-11-2013 |
20130093436 | ELECTROMAGNETIC METHOD FOR SENSING THE RELATIVE POSITION OF TWO ITEMS USING COUPLED TUNED CIRCUITS - An electromagnetic method for sensing the relative position of two items using coupled tuned resonant circuits. Two co-resonant tuned circuits are attached to two items | 04-18-2013 |
20130141117 | IMPEDANCE RESONANCE SENSOR FOR REAL TIME MONITORING OF DIFFERENT PROCESSES AND METHODS OF USING SAME - Processes and apparatuses are provided for contactless measuring or monitoring in-situ and in real time composition or other electromagnetic impedance correlated properties of liquid or gaseous substances or bulk materials. One or more apparatus may include a resonance type impedance sensor having at least two coils, at least one coil of the at least two coils being at least one excitation coil connectable to at least one alternating current source with frequency sweep, at least one other coil of the at least two coils being at least one sensing coil connectable to at least one data processing system. The one or more methods may include calculating changes in amplitude and resonant frequency induced by electromagnetic interaction between said sensor and object to determine impedance of said object under test; and matching said impedance with predetermined calibration data to determine said chemical or physical properties of said object under test. | 06-06-2013 |
20130176035 | WIRELESS MONITORING OF LABORATORY ANIMALS - Systems and methods for monitoring laboratory animals includes a tag comprising an inductive element and a capacitive element attached to a portion of a laboratory animal. The position of the portion is detected by monitoring the effect of the tag on a time-varying magnetic field having different frequencies, one near tag resonance, and one away from tag resonance. | 07-11-2013 |
20130176036 | FIELD DEVICE FOR DETERMINING AND/OR MONITORING A CHEMICAL OR PHYSICAL PROCESS VARIABLE IN AUTOMATION TECHNOLOGY - A field device for determining and/or monitoring a chemical or physical, process variable in automation technology, which has at least a first electronic or electrical component and a second electronic or electrical component. The first component has an energy transmitting antenna and the second component has an energy receiving antenna. Between the two components a predetermined distance is provided, which sets the first component and the second component apart from one another. The predetermined distance is filled, at least partially, with a dielectric medium. The energy transmitting antenna is so embodied and/or arranged that it supplies the second component with energy continuously or at predetermined time intervals. | 07-11-2013 |
20130285677 | WATER CONTENT MEASURING APPARATUS - A water content measuring apparatus, for measuring water content present in a fluid flow through a tube, includes a pulse generator for generating in operation a temporal series of excitation pulses, a coil arrangement disposed around the tube adapted to be excited into resonance by the series of excitation pulses and interact with the fluid flow through the tube, and a signal processor adapted to receive resonance signals from the coil arrangement for determining a water content present within the tube. The coil arrangement includes a resonance coil having a length-to-diameter ratio which is at least 3:1, and wherein the resonance coil includes at least 10 turns. | 10-31-2013 |
20140002111 | RESONANT SENSOR AND AN ASSOCIATED SENSING METHOD | 01-02-2014 |
20140176159 | INDUCTIVE TOUCH KEY SWITCH SYSTEM INCLUDING A DEFLECTION TRANSLATION MECHANISM - A key switch assembly is provided wherein a spacer is used to isolate the key switch sensing circuit from the front panel of the device. A button assembly is provided to translate a deflection of the front panel of the device to a target coupled to a sensor of the sensing circuit. | 06-26-2014 |
20140184245 | POSITION INDICATOR AND CAPACITOR - A position indicator includes a resonance circuit housed in a casing and having an inductance element and a capacitor variable in capacitance, such that the resonance circuit resonates at a predetermined frequency. The position indicator is electromagnetically coupled to a position detecting device. The capacitor includes a dielectric, an electrode disposed on one side of the dielectric, and a trimming electrode disposed on another side of the dielectric such that at least one part of a region of the trimming electrode is opposed to the electrode with the dielectric interposed in between, to form the capacitance of the capacitor. The capacitor is housed in the casing such that the at least one part can be exposed from the casing. The area of the at least one part exposed from the casing to the outside is changed so as to correspond to a resonance frequency desired for the resonance circuit. | 07-03-2014 |
20140197850 | Piezoelectric Sensor for the Detection and Characterization of at Least One Biochemical Element - A piezoelectric sensor for the detection and characterization of at least one biochemical element in a fluid, has a piezoelectric substrate exhibiting at each of its opposite faces at least one conducting surface forming electrodes, the electrodes being linked to an electrical generator, one at least of the surfaces being wrapped in a functionalized film, the electrodes form transmission lines exhibiting a zone constituting an induction loop for the excitation of the piezoelectric substrate, the link between the electrodes and the generator being ensured by inductive coupling. A system implementing such a sensor, as well as applications of such a sensor, are described. | 07-17-2014 |
20140203823 | IMPLANTABLE MEDICAL DEVICE DEPTH ESTIMATION - A method includes applying a signal to a primary coil of an external charging device. The signal causes the primary coil to inductively couple to a secondary coil of an implantable medical device that is implanted within tissue of a patient. The method also includes measuring a current at the primary coil. The method further includes estimating a depth of the implantable medical device within the tissue of the patient based on the measured current. | 07-24-2014 |
20140361792 | RESOLVER EXCITATION APPARATUS - A resolver excitation apparatus that adjusts amplitude of a sinusoidal excitation source signal to generate an excitation signal having predetermined amplitude in order to excite an exciting winding of a resolver. A parallel resonant circuit having a parallel resonant element that functions as parallel resonant impedance for impedance of the excitation winding. A series resonant circuit having a series resonant element that functions as series resonant impedance for the impedance of the excitation winding. | 12-11-2014 |
20140368220 | NON-CONTACT SENSING MODULE AND METHOD OF MANUFACTURING THE SAME - A non-contact sensing module includes a coil printed circuit board in which a reference pattern coil may be formed at an upper surface and in which a sensing pattern coil may be formed at a lower surface and that has a mounting hole at the center, and a main printed circuit board that may be coupled to the mounting hole and that may be vertically disposed at an upper surface of the coil printed circuit board and that may be electrically connected to the reference pattern coil and the sensing pattern coil. | 12-18-2014 |
20150048844 | CORROSION DETECTION SENSOR EMBEDDED WITHIN A CONCRETE STRUCTURE WITH A DIFFUSION LAYER PLACED OVER THE SACRIFICIAL TRANSDUCER - A corrosion detection sensor embedded within a concrete structure. The sensor includes a hermetically sealed resonant circuit that is a resistor-inductor-capacitor (RLC) circuit. The sensor further includes a sacrificial transducer that is inductively or capacitively coupled to the resonant circuit, where the sacrificial transducer is exposed to an environment outside the sensor to monitor corrosion of steel reinforcement in the concrete structure. Additionally, the sensor includes a protective cementitious housing surrounding the resonant circuit and the sacrificial transducer. The sensor further includes a diffusion layer placed over the sacrificial transducer, where the diffusion layer enables a dispersion of a chemical species over the sacrificial transducer. In this manner, a more uniform distribution of the chemical species over the surface of the sacrificial transducer mitigating the localized corrosion is ensured. Furthermore, such a design is less susceptible to false positives. | 02-19-2015 |
20150061699 | POSITION DETECTION METHOD, POSITION DETECTION APPARATUS, ANTENNA APPARATUS, AND DISPLAY APPARATUS - Provided are a position detection method that selects one antenna at a time from a plurality of loop antennas, transmits, through the selected loop antenna, an electromagnetic signal to a pointer that indicates a screen unit, receives, from the pointer, a resonance signal corresponding to the electromagnetic signal transmitted through the selected loop antenna, and extracts polar coordinates including a distance value and an angle value of a point on a screen unit indicated by the pointer, based on a distribution of a signal strength of a resonance signal received through each of the plurality of loop antennas, a position detection apparatus, a display apparatus, and an antenna apparatus appropriate for extracting polar coordinates. | 03-05-2015 |
20150109000 | SYSTEMS, METHODS, AND APPARATUS FOR INCREASED FOREIGN OBJECT DETECTION LOOP ARRAY SENSITIVITY - This disclosure provides systems, methods and apparatus for detecting foreign objects. An apparatus for detecting a presence of an object is provided including a plurality of electrically conductive loops arranged in an array. The apparatus includes a sensor circuit configured to determine a characteristic associated with each of the plurality of loops. The apparatus includes a hardware processor configured to, for each loop of the plurality of loops, determine a parameter based on the characteristic associated with the loop and the characteristic associated with at least one adjacent loop. The hardware processor may be further configured to determine the presence of the object based on the parameter. The parameter may comprise a sum of a difference between the characteristic associated with the loop and a reference value for the characteristic, and a difference between the characteristic associated with each of the at least one adjacent loop and the reference value. | 04-23-2015 |
20150123681 | WHEEL CIRCUIT USING ELECTROMAGNETIC INDUCTION AND ELECTRONIC PEN INCLUDING THE SAME - A wheel circuit using electromagnetic induction and an electronic pen are provided. The wheel circuit includes a rotary encoder configured to be rotated according to a user operation and includes at least one port, a resonant unit configured to be coupled with a port of the at least one port, and at least one capacitor including one end which is coupled with at least one other port which is not coupled with the resonant unit among the at least one port. The at least one capacitor has a capacitance different from each other, wherein at least one other capacitor of the at least one capacitor is connected to the resonant unit according to rotation of the rotary encoder to vary a resonant frequency. | 05-07-2015 |
20150145529 | COIL UNIT AND APPARATUS FOR DETECTING FOREIGN MATTER - A power feeding coil unit (a coil unit) is provided with a power feeding coil (a coil for power transmission) and an apparatus for detecting foreign matter. The apparatus for detecting foreign matter is provided with a plurality of resonators having a resonator coil and capacitor and also an excitation coil for exciting the plurality of resonators. The plurality of resonators are disposed in rows and columns to cover at least an area interlinking with a magnetic flux generated by the power feeding coil. The excitation coil makes resonators adjacent in a row direction and a column direction among the plurality of resonators to generate an alternating magnetic field with resonance frequencies different from each other within a frequency band in which the power feeding coil is not excited. | 05-28-2015 |
20150145530 | COIL UNIT AND APPARATUS FOR DETECTING FOREIGN MATTER - The present invention aims to provide a coil unit for improving an accuracy in detecting foreign matter and an apparatus for detecting foreign matter which improves the accuracy in detecting foreign matter when a power is transmitted in a contactless manner. A power feeding coil unit L | 05-28-2015 |
20160011235 | METHOD OF INTERFACING AN LC SENSOR AND RELATED SYSTEM | 01-14-2016 |
20160084781 | APPARATUS AND METHOD FOR IDENTIFYING OBJECT - An element device and a method for identifying an object are provided. The method includes applying a current to a first coil from among a plurality of coils of the electronic device, measuring an induced current of a second coil among the plurality of coils, the second coil adjacent to the first coil, identifying information on an object which is located outside the electronic device based on the induced current, and performing a designated function based on a result of the identifying. | 03-24-2016 |
20160187275 | Sensing System Using a Marginal Oscillator - A sensor system comprises a marginal oscillator. A tank circuit comprises inductive and capacitive elements including a probe arranged to generate an electromagnetic field in a sensing region. A non-linear drive circuit drives oscillation of the tank circuit by supplying a differential signal pair of complementary signals across the tank circuit, sustaining the oscillation on the basis of at least one of the complementary signals. A detection circuit detects a characteristic of the oscillation of the tank circuit that is dependent on the electromagnetic properties of the contents of the sensing region and to derive a signal representing the at least one characteristic. The differential signaling provides numerous advantages, including improved accuracy and signal-to-noise. | 06-30-2016 |
20170234701 | RESONANT IMPEDANCE SENSING WITH A NEGATIVE IMPEDANCE CONTROL LOOP IMPLEMENTED WITH SYNCHRONIZED CLASS D AND OUTPUT COMPARATORS | 08-17-2017 |