Abstract: Measuring circuits including switched capacitors, and related systems, methods, and devices are disclosed. A measurement circuit includes a flying capacitor, a grounded capacitor, a first switch, a second switch, a third switch, and a fourth switch. The first switch is configured to selectively electrically connect an electrochemical cell cathode node to a first terminal of the flying capacitor. The second switch is configured to selectively electrically connect an electrochemical cell anode node to a second terminal of the flying capacitor. The third switch is configured to selectively electrically connect the first terminal of the flying capacitor to a third terminal of the grounded capacitor. The fourth switch is configured to electrically connect the second terminal of the flying capacitor to a fourth terminal of the grounded capacitor. The fourth terminal is electrically connected to the reference voltage potential node.

Abstract: Disclosed are a high-precision resistance measurement system and method combining a micro-differential method and a ratiometric method. The system includes a constant-current source, a reference resistor, a first differential amplifier, a programmable gain amplifier (PGA), an ADC, a microprocessor, a DAC and a to-be-measured resistor interface. The reference resistor and a to-be-measured resistor are connected in series between the constant-current source and ground. The voltage across the reference resistor is inputted to the first differential amplifier, and the output of the first differential amplifier is used as the reference voltage for the ADC and the DAC. The single-ended voltage to ground of the to-be-measured resistor and the output voltage of the DAC are inputted to the PGA in differential manner, and the PGA outputs the amplified difference voltage to the ADC. The output terminal of the ADC and the input terminal of the DAC are both connected to the microprocessor.

Abstract: A voltage detection circuit measures a plurality of cell voltages of an assembled battery configured by connecting a plurality of cells in series. The voltage detection circuit includes a plurality of input terminals connected to respective electrodes of the plurality of cells through a plurality of voltage detection lines; a multiplexer that periodically selects and outputs voltages of a plurality of cells in a group, a plurality of series cells configured as the group; an analog-to-digital (AD) converter that AD-converts an output voltage from the multiplexer and outputs digital data of the output voltage; and a control circuit that controls a timing for the selection by the multiplexer and a timing for the AD conversion. The control circuit switches over a time interval for which the multiplexer selects each of the cells to change a period of the AD conversion.

Abstract: Some disclosed embodiments relate, generally, to shaping a waveform of a reference signal used by a driver of a touch sensor to limit electromagnetic emissions (EME) emitted by a touch sensor during a sensing operation. Some disclosed embodiments relate, generally, to a DAC referenced touch sensor driver and controlling an amount of EME emitted at a touch sensor using shapes of reference signals used by a touch detector to detect touches at the touch sensor. Some disclosed embodiments relate, generally, to compensating for effects of foreign noise at a touch sensor. And more specifically, to changing a shape of a reference signal based on a change to a sampling rate made to compensate for foreign noise.

Abstract: A circuit arrangement for resistance measurement comprises a capacitor coupled between a first potential node and a second potential node, a pair of terminals that comprises a first terminal and a second terminal, the first and second terminals being coupleable to one of the at least one resistor. The circuit arrangement further comprises a set of circuit branches comprising a first circuit branch, a second circuit branch, a third circuit branch and a fourth circuit branch, each comprising a switch switchable between a conductive state and an insulating state. The circuit arrangement further comprises the first terminal being coupled to the first potential node via the first circuit branch and the second circuit branch being connected in parallel. The circuit arrangement further comprises the second terminal being coupled to the second potential node via the third circuit branch and the fourth circuit branch being connected in parallel.

Abstract: A detector for measuring a resistance of a variable resistance sensor (VRS) that varies with respect to a time-varying stimulus (e.g., temperature) includes a voltage reference having variation with respect to operating conditions and a linearized digital-to-analog converter (LIDAC) having a known transconductance that uses the voltage reference to generate a current for pumping into the VRS to cause the VRS to generate a voltage sensed by the detector. The sensed voltage includes error due to the variation of the voltage reference. The detector also includes a programmable gain amplifier (PGA) that gains up the sensed voltage to generate an output signal, an ADC that converts the output signal to a digital value, and a digital processor that computes the resistance of the VRS using the digital value and the known transconductance. The PGA is non-varying with respect to the time-varying stimulus.

Abstract: Systems and methods for monitoring operating conditions of a programmable device are disclosed. The system may include a root monitor configured to generate a reference voltage, a plurality of sensors distributed across the device, and a plurality of satellite monitors distributed across the device. Each of the satellite monitors may be coupled to a corresponding sensor via a local interconnect, and may be configured to convert analog signals generated by the sensor into digital data indicative of one or more operating conditions of an associated circuit. In some implementations, each satellite monitor may include a circuit to store a local reference voltage, an analog-to-digital converter (ADC) to convert the analog signals into digital codes, a calibration circuit to generate a correction factor indicative of errors in the digital codes, and a correction circuit to correct the digital codes based on the correction factor.

Abstract: A built-in self-test (BIST) methodology and apparatus provide for testing and calibration of an integrated circuit oscillator circuit topology that uses a one-pin (a single-pin) external resonator. The method employs dedicated test circuitry, also referred to herein as BIST apparatus, for the pass/fail verification of both the active and passive building blocks of the oscillator. At the same time, the methodology ensures accurate calibration and matching of the capacitors using dedicated digital circuitry and algorithms.

Abstract: The invention relates to a method of monitoring a person (101) having an interest to an object. The method comprising steps of: (210) providing a data processor (111) for obtaining interaction data related to a remote interaction between the person and at least one of a plurality of the objects (131, 132, 133), (240) using the data processor for analysis of the interaction data to identify a particular one of the objects (133), to which the person has the interest, and (250) obtaining additional data related to the particular object for informing the person about the particular object. The analysis of the interaction data may comprise a step (220) of identifying a remote location where the interest of the person is focused, and a step (230) of determining locations of the objects with respect to the remote location.

Abstract: Capacitance detecting circuit is disclosed for fingerprint sensing and other applications. The capacitance detecting circuit includes a first capacitor, an integrator, a second capacitor, a comparator, and a counter. The integrator can generate an integrating output voltage and includes a first single-ended amplifier and at least one integration capacitor. The first single-ended amplifier includes a first input terminal and an integrating output terminal. The comparator can generate a comparing output and include a negative input terminal coupled to the integrating output terminal of the first single-ended amplifier, a positive input terminal to receive a reference voltage, and a comparing output terminal to output the comparing output voltage. The counter is coupled to the comparing output terminal and can generate a counter output. A connection between the second capacitor and the first input terminal is controlled to be conducted or cutoff according to the comparing output.

Abstract: An analog-to-digital converter (ADC) comprising successive approximation circuitry, a capacitive analog-to-digital converter (CDAC), and capacitor mismatch measurement circuitry. The successive approximation circuitry is configured to control conversion of an analog signal to a digital value. The CDAC is coupled to the successive approximation circuitry. The CDAC includes a plurality of capacitors. The capacitor mismatch measurement circuitry is coupled to the CDAC. The capacitor mismatch measurement circuitry includes a first oscillator circuit, a second oscillator circuit, and counter circuitry. The first oscillator circuit is configured to oscillate at a frequency determined by a capacitance of one of the capacitors. The second oscillator circuit is configured to generate a predetermined time interval. The counter circuitry is configured to count a number of cycles of oscillation of the first oscillator in the predetermined time interval.

Abstract: A device (100) which comprises a deliverable sensor (202), a container (101) for receiving a liquid (1), a container environment (103) and a signal processing circuit (2), the input side (11) of which can be connected circuitry-wise to the sensor (102). The device (100) is designed to perform a capacitive liquid level measurement in normal operation using the sensor (102), wherein a threshold value can be predefined for the signal processing circuit (2) for normal operation, the device (100) comprises a classification module (104), i. which can be connected with an input side or line connection (105) circuitry-wise to the sensor (102), ii. which is designed to make a capacitive measurement of the liquid (1) in the container (101) using the sensor (102), and iii. which can be connected circuitry-wise (106) to the signal processing circuit (2) in order to trigger the specification of a threshold value using the sensor (102) for capacitive measurement of the liquid (1).

Abstract: A method may include controlling a first switch to charge a reference capacitor to a first voltage level by applying a first voltage. The method may also include receiving a first analog signal from a touch sensor electrode at an input of an Analog to Digital Converter (ADC) and converting the first analog signal to a first digital value provided at an output of the ADC. In certain embodiments, the method may additionally include controlling a second switch to charge the reference capacitor to a second voltage level by applying a second voltage, receiving a second analog signal from the touch sensor electrode at the input to the ADC, and converting the second analog signal to a second digital value at the output of the ADC. The method may further include detecting a touch to the touch sensor device based on the first digital value.

Abstract: A portable audio device may be configured to measure load characteristics of headphones. The device may measure direct current (DC) and/or alternating current (AC) characteristics of the load. These characteristics may be measured by an audio component, such as an audio codec chip or integrated circuit (IC) controller, and reported to software or firmware executing on a processor coupled to the audio component. The software or firmware may then take action based on the measured load characteristics. For example, the load characteristics may be compared to a database of headphones and their known load characteristics to determine a particular headphone model or type of headphone attached to the audio output. The processor may then apply an appropriate equalization curve.

Abstract: A capacitive position sensing system has a pickup electrode, a shield electrode partially enclosing the pickup electrode, and an essentially grounded relatively movable target near the pickup electrodes; a capacitance-to-digital converter, and switching means for connecting each electrode in turn to the converter input or to ground. A capacitive position sensing method in the system includes measuring a first capacitance C1 of at least one pickup electrode set with the shield electrode set grounded, measuring a second capacitance C2 of at least one shield electrode set with the pickup electrode set grounded, and measuring a third capacitance C3 of the pickup electrode set and the shield electrode set connected together; and calculating a first result indicating a position of a target using the first capacitance C1, the second capacitance C2 and the third capacitance C3.

Abstract: In some examples, a method includes controlling a first set of switches to deliver a first voltage signal through a first set of capacitors to a common node. The method also includes controlling a second set of switches to deliver a second voltage signal through a second set of capacitors to the common node, wherein the first set of capacitors is electrically connected to the second set of capacitors by the common node. The method further includes measuring a time duration to discharge the common node. The second voltage signal includes an opposing polarity to the first voltage signal.

Abstract: A differential capacitive output pressure sensor device includes a pressure sensor diaphragm layer comprising a pressure sensing diaphragm portion, a movable electrode on the pressure sensing diaphragm portion, a fixed electrode, and a device layer electrode. The pressure sensor device further includes a device layer including a fixed element connected to the device layer electrode and a movable element connected to the movable electrode. As the pressure changes, the pressure sensing diaphragm portion including the movable electrode and the movable element move. This changes the capacitance between the movable electrode and the fixed element inversely to the change in capacitance between the fixed electrode and the moveable element. Accordingly, a differential capacitive output is provided that has improved linearity with respect to the pressure change and increased sensitivity allowing the change in pressure to be measured readily and accurately.

Abstract: An input device (10) has a contact plate (12) having a contact surface (14) and being least partially coated with an electrical resistive layer (16) on a surface opposite the contact surface (14). The electrical resistive layer (16) has at least two electrically conducting contacts (18). A measuring circuit (20) is provided for measuring a sensing capacitor (24) formed by the electrical resistive layer (16) and an electrostatically chargeable object (22) arranged at a contact position on the contact surface (14). Further, a processing unit is provided for determining coordinates (X, Y) of the contact position of the electrostatically chargeable object (22) on the contact surface (14) by means of a determination of the ohmic resistances (Rn) between the contact position of the electrostatically chargeable object (22) and the electrically conducting contacts.

Abstract: A method and system for monitoring the health of a battery is provided. A precision frequency can be determined for the battery by applying one of an AC current or voltage perturbation across a frequency sweep with impedance spectroscopy equipment to obtain an impedance response; collecting data related to the impedance response at a plurality of various states of charge within a recommended voltage window of the battery; plotting the collected data on one or more impedance curves; and analyzing the one or more impedance curves at the various states of charge to determine the precision frequency. Next, one of an AC current or voltage perturbation can be applied at the precision frequency resulting in an impedance response. The value of the impedance response can be recorded, and a determination can be made of a battery classification zone that the impedance value falls within.

Abstract: A sensing method is used for a capacitive sensing device, wherein the capacitive sensing device has a plurality of capacitive sensing components, each of which is charged or discharged by a charging component respectively. The sensing method comprises the steps of: a first sampling step of sampling at least one of charging or discharging time of a capacitive sensing component of the plurality of capacitive sensing components to determine a first sample time for the component sampled, wherein the component sampled and at least one another component of the plurality of capacitive sensing components are charged or discharged simultaneously during the first sampling step; a first comparing step of comparing the first sample time for the component sampled with a reference time; and an outputting step of outputting a trigger signal in the event that the first sample time exceeds the reference time.

Abstract: An anti-entrapment system for preventing an object from being entrapped by a translating device such as a vehicle window includes a capacitance sensor and a controller. The sensor has a jacket with a cavity, a dielectric element within the cavity, and first and second electrical conductors. The conductors are within the cavity on opposite sides of the dielectric element such that the conductors are separated from one another by a separation distance. The capacitance of the sensor changes in response to an electrically conductive object moving in proximity to at least one of the conductors. The controller is configured to control a translating device as a function of the capacitance of the sensor. The jacket is attachable to a seal configured to receive the translating device.

Abstract: An inductive sensor includes a primary winding, two secondary windings and a moveable target, the primary winding being centered about a central axis and carrying a high-frequency alternating current which can induce a voltage in secondary windings, the secondary windings also being centered about the central axis and made up of a number k of substantially identical loops, which are successively crossed and arranged opposite the primary winding. In this case, the target is made up of a part having p=1 angular sector with an angular opening. The opening of the angular sector of the target is less than that of a loop of secondary winding with a deviation calculated such as to eliminate the fourth harmonic of the linearity deviation Fourier decomposition, between the measured angular value and real angular value for the position of the target over the measurement course.

Abstract: An AC voltage detection circuit includes a conversion module, a comparison module, and a prompt module. The conversion module connects to an AC power source and converts the AC voltage provided by the AC power source to an AC current, and then converts the AC current to a direct current (DC) voltage reflecting the AC voltage. The comparison module is connected to the conversion module, and compares the DC voltage with a first predetermined voltage and a second lesser predetermined voltage, and produces a control signal when the DC voltage is greater than the first predetermined voltage or less than the second predetermined voltage. The prompt module produces a prompt signal when receiving the control signal.

Abstract: A digital sine wave may be converted to an analog signal at a digital to analog converter (DAC). The converted analog signal may be supplied to a device and an analog return signal from the device may be passed through a relaxed anti-aliasing filter and converted to digital code words at an analog to digital converter (ADC). An impedance may be calculated from the results of a Fourier analysis of the digital code words. The ADC and DAC clock frequencies may be asynchronous, independently variable, and have a greatest common factor of 1. The clock frequencies of the ADC and/or DAC may be adjusted to change a location of images in the ADC spectrum. By using these different, adjustable clock frequencies for the ADC and the DAC, an analog signal may have increased aliasing without introducing signal errors at a frequency of interest.

Abstract: A method for minimizing stray current in capacitive sensor data includes receiving a first input from a first wire of a wire harness, the wire harness comprising a plurality of twisted wires, the first input comprising a first signal comprising first sensor data and stray current; receiving a second input from a second wire of the wire harness, the second input comprising a second signal comprising stray current; and subtracting the second signal from the first signal to determine the first sensor data. A system for minimizing stray current in capacitive sensor data is also provided.

Abstract: A calibration apparatus and method for a capacitive sensing device, in which a calibration capacitor device connects to the capacitive sensing device which is connected to an integration circuit that generates a voltage output and a latch output, a transforming circuit transforms a sensitivity calibration parameter into a pair of corresponding analog signal outputs, and an offset calibration parameter into a corresponding analog signal output, at least two first switches between the pair of corresponding analog signal outputs and a fixed potential according to system clock's levels, and at least a third switch switches between the corresponding analog signal output and another fixed potential according to the system clock's levels. The apparatus determines the switch between the pair of signal outputs according to the latch output.

Abstract: A voltage sensing device with which high-precision voltage sensing is possible without the need to obtain a unique correction constant for each device. A pair of voltage input nodes NCk and NCk-1 is selected from voltage input nodes NC0-NCn in switch part 10, and they are connected to sensing input nodes NA and NB in two types of patterns with different polarity (forward connection, reverse connection). Sensing input nodes NA and NB are held at reference potential Vm by voltage sensing part 20, and current Ina and Inb corresponding to the voltage at voltage input nodes NCk and NCk-1 flows to input resistors RIk and RIk-1. Currents Ina and Inb are synthesized at different ratios in voltage sensing part 20, and sensed voltage signal S20 is generated according to the synthesized current Ic. Sensed voltage data S40 with low error is generated according to the difference between the two sensed voltage signals S20 generated in the two connection patterns.

Abstract: A method and device are provided for demodulation of an output signal from a transducer (1) driven by an alternating excitation signal having an excitation frequency. The transducer produces an amplitude-modulated output signal (y(t)) containing the quantity to be measured. The device has sampling units (5,6,7) to sample the output signal from the transducer and the output signal from the excitation unit, and a computation unit (8) to compute a first complex valued quantity ( Y) including information on the amplitude and phase of the output signal at the excitation frequency based on sampled values of the output signal from the transducer, compute a second complex valued quantity (?, ?) including information on the amplitude and phase of the excitation signal at the excitation frequency based on sampled values of the excitation signal, forming a complex valued output quotient between the first and second complex valued quantities, and compute the demodulated output signal (Od) based on the output quotient.

Abstract: The present invention refers to a method for the precise measurement of dependency on amplitude and phase of a plurality of high frequency signals, preferably in the synchrotron accelerator of elementary particles. The essence of the solution according to the invention lies in that with a single measuring device and without any aliasing it is achieved a resolution of 0.2 micron and repeatability of measurements of 1 micron down to the lower frequency limit of a few MHz.

Abstract: Apparatus (1) and corresponding method for measuring a current (10) in which a charge integrating circuit (2) integrates charge from the current to be measured (10) and applies a resulting change in voltage to a comparator circuit (4) that compares the input voltage (12) with a threshold voltage level (Vthreshoid) and provides an output (14) responsive thereto to a logic circuit (6) that generates a feedback signal (16) dependent upon the comparator output (14) and provides the feedback signal (16) to the charge integrating circuit (2) that integrates charge from the received feedback signal (16) in opposition to the integrating of the charge from the current to be measured (10). The logic circuit (6) generates an output signal (18), based upon the comparator circuit output (14) and dependent upon the level of the current to be measured (10), for example a pulse (50) of a width (TOUT) dependent upon the level of the current (10).

Abstract: A capacitive sensing system are configured to sense a capacitance value and convert the sensed capacitance value to a digital format. The capacitive sensing system provides good selectivity and immunity to noise and interference, which can be further enhanced by enabling spread spectrum excitation. In some embodiments, the capacitive sensing system utilizes a sinusoidal excitation signal that results in low electromagnetic emissions, limited to narrow frequency band. In some embodiments, the capacitive sensing system is configured to operate in a spread spectrum mode, in which the majority of the excitation signal power is carried in the assigned bandwidth. The excitation frequency and the bandwidth of the spread spectrum excitation signal are programmable in a wide range, which allows for avoiding frequency conflicts in the operating environment.

Abstract: Novel system and methodology for detecting a Powered Device (PD) in a Power over Ethernet (PoE) system. A PD probing circuit generates a detection signal supplied to the PD and determines a PD response signal produced in response to the detection signal. Based on the PD response signal, the control circuit determines a detection value for identifying the PD. In particular, the control circuit concludes that the PD is a device satisfying a PoE standard if the detection value is in a first predetermined range, and concludes that the PD is a legacy PD device if the detection value is in a second predetermined range outside of the first predetermined range.

Abstract: A first capacitor and a second capacitor are charged until voltage at the second capacitor settles to a settling voltage. While charging, the first capacitor is alternately switched between a current source and ground. When the settling voltage is reached, charging of the first capacitor is halted. The second capacitor continues to be charged until voltage at the second capacitor reaches a reference voltage. The amount of time it takes for the settling voltage to reach the reference voltage corresponds to a measure of capacitance on the first capacitor.

Abstract: A sensor incorporates a dual range ASIC (Application Specific Integrated Circuit) for accurately sensing and measuring sensor input over extensive range along with an improved resolution. The sensor can incorporate an ASIC utilizing signals from a MEMS-based piezoresistive Wheatstone bridge. Signals can also come from capacitive pressure measurement sources. The signals can be converted to digital bit counts where calibration coefficients can be implemented to achieve high precision. The calibration coefficients corresponding to bit counts can be compared with transition points that are recorded into ASIC for effectively distinguishing different sensor ranges. The transition points can be stored in an EEPROM fabricated to suit ASIC applications.

Abstract: System and method for measuring series-connected cell voltages using a flying capacitor with self-calibration. In at least one embodiment of a system of the present disclosure, the system comprises a capacitor, a switch, an amplifier, an analog-to-digital converter, and a precision voltage device. In an exemplary method of the present disclosure, the method comprises the steps of charging a capacitor, obtaining a charge voltage reading, discharging the capacitor for a known duration, obtaining a discharge voltage reading, and signaling a malfunction of the discharge voltage reading is greater than a predetermined voltage level.

Abstract: The invention refers to a method and an apparatus (1) for protecting people against leakage currents while using appliances such as home appliances or the like. The apparatus (1) is provided with a differential switch (20) normally open and a differential current transformer (39) which generates a signal proportional to the leakage current, an elaboration unit (50) interfaced with the latter acquires said signal and keeps the switch (20) closed until a dangerous condition is met, corresponding to an acquired signal having a magnitude greater than a limit value.

Abstract: An AC impedance measurement system is used for measuring the impedance of a DUT. A measured voltage is applied to a first DUT terminal by a first digital to analog converter, the voltage appearing at the second terminal of the DUT is monitored through an analog to digital converter and forced by a second digital to analog converter to a desired negligible value, and a digital controller determines the impedance of the DUT from the measured voltage and the current necessary to force the voltage appearing at the second terminal to the desired negligible value.

Abstract: Novel circuitry and methodology for detecting a Powered Device (PD) in a system for providing power to the PD. PD detection circuitry detects the PD in a first mode by providing detection current to probe the PD, and in a second mode by providing detection voltage to probe the PD. A control circuit determines that the PD is a valid device if the PD is detected both in the first mode and in the second mode.

Abstract: A transceiver system and method determining a voltage standing wave ratio (VSWR) is provided. The system includes at least one amplifier, a filter bank, a plurality of detectors, and at least one processor. The at least one amplifier receives an input signal. The filter bank is in electrical communication with the at least one amplifier. The plurality of detectors are in electrical communication with the filter bank, where a first detector of the plurality of detectors is in electrical communication with a first portion of the filter bank, and a second detector of the plurality of detectors is in electrical communication with a second portion of the filter bank. The at least one processor is in electrical communication with the plurality of detectors, and estimates a VSWR based upon voltages detected by the first and second detectors.

Abstract: An impedance conversion circuit including: a first voltage-to-current converter and a second voltage-to-current converter supplied with differential input signal voltages; an inverting amplifier; and a third voltage-to-current converter for feedback; wherein a first resistance and a second resistance are connected in series with each other between an input terminal and an output terminal of the inverting amplifier, an output terminal of the first voltage-to-current converter is connected to the input terminal of the inverting amplifier, an output terminal of the second voltage-to-current converter is connected to a connection node of the first resistance and the second resistance, the output terminal of the inverting amplifier is connected to an input terminal of the third voltage-to-current converter, an output terminal of the third voltage-to-current converter is connected to an input terminal of the first voltage-to-current converter, and an impedance is connected between the connection node and a ground.

Abstract: A system and method for measuring voltage of individual cells connected in series includes a single flying capacitor. The capacitor stores the charge of one of the cells such that an analog-to-digital converter (ADC) connected to the capacitor may process an accurate representation of the voltage of the cell being measured. A plurality of switches electrically connects and disconnects the cells from the capacitor. A controller is in communication with the ADC and the switches for sequencing the switches and recording the voltage measurements of each cell. At least one precision voltage reference device is included to provide the ADC a reference voltage to provide self-calibration.

Abstract: A digitizing ohmmeter system for providing a digital resistance ratio measurement includes a high impedance current source providing a DC excitation current to an impedance-varying input sensor and a reference resistor and an ADC circuit including a charge-balancing modulator and a digital post processing circuit. The same DC excitation current passes through both the input sensor and the reference resistor. The system utilizes a switched capacitor input stage to sample the voltage across the input sensor and the voltage across the reference resistor to generate an input voltage step and a reference voltage step which are coupled to the modulator of the ADC circuit. The digitizing ohmmeter system thereby realizes fully ratiometric operation such that neither a precise current source nor a precise voltage source is required for accurate resistance ratio measurements and only a stable known reference resistor is necessary for accurate absolute resistance measurements.

Abstract: The present disclosure relates to apparatus and methods for measurement of analog voltages in an integrated circuit. In particular, the apparatus includes an on-chip digital-to-analog converter configured to receive a variable digital input code and output a corresponding analog voltage corresponding to the variable digital input code. The apparatus also includes an on-chip comparator circuit configured to receive the analog voltage output by the digital-to-analog converter and a test analog voltage as inputs and to provide an output indicating the test analog voltage. Further, the apparatus includes an on-chip logic operative to determine the test analog voltage based on the output of the comparator circuit. A corresponding method is also disclosed.

Abstract: A apparatus and method for creating a universally usable and configurable sensor platform which is used in conjunction with various sensor and sensing elements to sense and measure environmental conditions which incorporates inputs from multiple sensors 6-9 and 12-14. The apparatus incorporates an oscillator 3 which provides a signal whose frequency varies according to the inputs from sensors 6-9 and 12-14 in combination with a microprocessor 1. A cordic block 61 allows for supplemental calculations of trigonometric operations and functions. An output unit 2 converts the signals received from microprocessor 1 into a variety of serial protocols.

Abstract: A recording medium detecting system includes a magnetic field-generating unit that generates an alternating magnetic field in a predetermined particular region, a detecting unit provided close to the particular region, that detects a change in magnetic flux density not smaller than a predetermined magnetic-flux-density difference B2, and a recording medium, containing multiple magnetic wires made of a magnetic material and formed in a wire shape having a predetermined length, that causes a large Barkhausen effect when the alternating magnetic field is applied. A magnetic-flux-density difference B1 detected by the detecting unit at an installation position thereof when the recording medium is placed in the particular region is not smaller than the magnetic-flux-density difference B2.

Abstract: An impedance conversion circuit including: a first voltage-to-current converter and a second voltage-to-current converter supplied with differential input signal voltages; an inverting amplifier; and a third voltage-to-current converter for feedback; wherein a first resistance and a second resistance are connected in series with each other between an input terminal and an output terminal of the inverting amplifier, an output terminal of the first voltage-to-current converter is connected to the input terminal of the inverting amplifier, an output terminal of the second voltage-to-current converter is connected to a connection node of the first resistance and the second resistance, the output terminal of the inverting amplifier is connected to an input terminal of the third voltage-to-current converter, an output terminal of the third voltage-to-current converter is connected to an input terminal of the first voltage-to-current converter, and an impedance is connected between the connection node and a ground.

Abstract: An apparatus for testing an integrated circuit that includes analog nodes is disclosed. In one aspect, an integrated circuit comprises testing circuitry and core logic circuitry. A memory in the testing circuitry stores data identifying analog nodes in the core logic circuitry and tolerance values associated with the analog nodes. A condition checker compares actual test values with the associated tolerance values. A main control unit controls the testing circuitry and synchronizes testing of the core logic circuitry. In another aspect, the testing circuitry includes a host computer interface useful for communicating with a host computer. A data memory in the testing circuitry is used for storing diagnostic data. The contents of the data memory may then be uploaded to a host computer. Test stimuli may be transmitted to the integrated circuit from a location outside the integrated circuit to perform testing.

Abstract: The invention is directed to a digital phase detector that comprises a splitter and phase shifter to receive a signal of a device under test and produce a first signal that is substantially identical to the received signal and a second signal that is phase shifted relative to the first signal. A first analog-to-digital channel processes the first signal to produce an in-phase and quadrature signals. The second signal is processed by a second analog-to-digital channel to produce a second set of in-phase and quadrature signals. The two sets of in-phase and quadrature signals are used to determine a phase difference between the signal of the device under test and a local oscillator signal associated with the two analog-to-digital channels. The invention is further directed to a direct digital synthesizer that is capable of use within the digital phase detector and in other applications.

Abstract: A method and apparatus for measuring or converting voltage, the method comprising: applying an input voltage to a primary delay line; applying a reference voltage to a timer delay line; propagating a delay signal through the primary delay line; propagating a timer signal through the timer delay line; establishing a sampling period based on the timer signal propagation; and measuring an extent of delay signal propagation along the primary delay line during the established sampling period, the measured signal propagation extent being indicative of a difference between the input voltage and the reference voltage.

Abstract: Monitoring a converter (1) includes detecting whether a value of an input variable (2) for the converter (1) assumes a first prescribed input reference value (41) and checking whether an output variable (3) from the converter (1) likewise assumes a corresponding, second prescribed output reference value (61). This means that the operation of the converter is tested only at occasional instants, specifically only using individual, prescribed values. The fact that only prescribed values (41, 61) are compared with instantaneous values of the input and output variables (2, 3) means that the invention can be implemented using very simple means. The method is particularly suitable for monitoring the operation of a converter (1) in a control or protective device for an electrical switchgear assembly. In this context, when a malfunction in the converter (1) is detected, all protective functions which are dependent on the converter (1) are preferably turned off.