Abstract: A method for measuring transconductance of an oscillating circuit is provided. The oscillating circuit includes an inverter. When an input terminal and an output terminal of the inverter are floated, the bias voltage of the inverter is obtained by measuring the output terminal thereof. Based on floating the input terminal and respectively providing a first voltage and a second voltage to the output terminal, a first current corresponding to the first voltage and a second current corresponding to the second voltage are measured from the output terminal. The first voltage and the bias voltage have the same voltage levels. An output resistor value of the inverter is obtained according to the first and second voltages and the first and second currents. The transconductance of the oscillating circuit is obtained according to the output resistor value.

Abstract: A voltage detection device that is connected to a DC circuit to which a DC voltage is applied and that detects the DC voltage applied to the DC circuit comprises a voltage conversion means for outputting a first voltage that increases as the DC voltage increases and a second voltage that decreases as the DC voltage increases, a voltage calculation means for inputting the first voltage and the second voltage outputted from the voltage conversion means and calculating the DC voltage based upon a difference between the inputted first voltage and the inputted second voltage, and a first failure judgment means for judging that failure has occurred if at least one of the first voltage and the second voltage is not inputted to the voltage calculation means.

Abstract: A power meter having complex quadrature output current and voltage filters provides power measurements in high amplitude and frequency variation and/or high jitter environments without requiring high computational overhead. A pair of filters, one for voltage and one for current each have a response determined by complex non-conjugate poles. The response of the filters is such that only the positive or negative half plane of the complex frequency spectrum is passed and provide complex outputs representing the real and imaginary parts of both the current and voltage. At least one indication of a power delivered to a load is computed from the complex current and voltage outputs, which may be the real and/or reactive power.

Abstract: The present invention relates to an apparatus capable of diagnosing the aging state of a power conversion system at ordinary times and its diagnosing method to ensure the reliability of a power conversion system. The apparatus includes a current sensing means for detecting the output current of a inverter switching module or an electrolytic capacitor, and measurement and diagnosis means for extracting elements related to the aging status of the power conversion system by receiving the output current waveform of the inverter switching module and magnitude of each harmonic or an impedance voltage signal of the electrolytic capacitor. Furthermore, it is preferable that the apparatus further includes a measurement current generation means for generating measurement current to be supplied to the electrolytic capacitor.

Abstract: A clamp-on current and voltage module for an electrical power monitoring system that monitors characteristics of power distributed through one or more power conductors includes a current transformer having a core divided into at least two parts so that the core can be installed around a power conductor without cutting the conductor. The transformer produces a current signal corresponding to current passing through the power conductor. A pair of clamping elements fit on opposite sides of the conductor, for gripping the conductor. The transformer core parts and the clamping elements have engaging surfaces that prevent relative movement between the CT enclosure and the power conductor in a direction transverse to the axis of the power conductor. A voltage sensor makes electrical contact with the power conductor and produces a voltage signal corresponding to the voltage on the power conductor.

Abstract: A medical treatment device, such as a dental treatment device, is described, the device including a drive unit for driving multiple different tools that are detachably connectable to the treatment device and a tool recognition device for recognizing whether a tool is connected to the treatment device and/or which of the different tools is connected to the treatment device. The tool recognition device includes a coil and an evaluation unit, wherein the coil is connected or connectable to an AC voltage sources, and the coil is inductively couplable to the different tools, so that an AC voltage signal that is specific for each tool and that can be associated with the particular tool by the evaluation unit can be generated.

Abstract: An operating state detection technique is provided which makes it possible to accurately detect an abnormality of a high-frequency heating apparatus. An anode current detected by the anode current detection resistor 40 of a magnetron is inputted into the A/D converter terminal of a microcomputer 27 on a control panel circuit board side. The current is subjected to an analog-to-digital conversion to thereby obtain an anode voltage IaDC value. The microcomputer 27 determines an operating state based on a plurality of the anode voltage IaDC values thus read. Further, the microcomputer 27 obtains a summed value of the IaDC values corresponding to one period of the revolution of rotary antennas 68, 69 to thereby determines the operating state of the high-frequency heating apparatus 100 based on the summed value.

Abstract: An operating state detection technique is provided which makes it possible to accurately detect an abnormality of a high-frequency heating apparatus. An anode current detected by the anode current detection resistor 40 of a magnetron is inputted into the A/D converter terminal of a microcomputer 27 on a control panel circuit board side. The current is subjected to an analog-to-digital conversion to thereby obtain an anode voltage IaDC value. The microcomputer 27 determines an operating state based on a plurality of the anode voltage IaDC values thus read. Further, the microcomputer 27 obtains a summed value of the IaDC values corresponding to one period of the revolution of rotary antennas 68, 69 to thereby determines the operating state of the high-frequency heating apparatus 100 based on the summed value.

Abstract: A current sensor includes a housing having a pair of first slits, a bus bar supported by the housing and electrically connected to a battery post provided on a battery, an annular shield member arranged so as to surround an axis extending in a direction in which a current is flowed in the bus bar, and a magnetic-electric conversion element provided on the housing to detect a magnetic flux density of a magnetic field generated when the current is flowed in the bus bar and produce an electric signal. The magnetic-electric conversion element is arranged between the first slits. The shield member is inserted into the first slits so that the shield member is mounted on the housing.

Abstract: An equipment monitoring device for monitoring a heating, ventilation, and air conditioning (HVAC) system configured to control an internal environment of a structure may include a current transformer configured to sense current being supplied from a power source to a first component of the HVAC system and a gauge configured to display the amount of current being supplied from the power source to the first component based on the current sensed by the current transformer.

Abstract: A power noise detecting device includes a plurality of power lines, and a power noise detecting part configured to detect power noise by rectifying voltages of the plurality of power lines and converting the rectified voltages into effective voltages.

Abstract: The power level of an RF signal is detected using a circuit having relatively low DC offset, high dynamic range, small frequency and temperature dependence and low flicker noise. According to one embodiment, the power detector circuit comprises a chain of amplifiers and a passive mixer. The chain of amplifiers converts the RF input signal to a supply-limited RF square wave signal. The passive mixer passively mixes the supply-limited RF square wave signal with the RF input signal and in response generates a rectified output signal that tracks the amplitude of the RF input signal.

Abstract: An electric current monitoring device is provided to be used in conjunction with a measuring instrument that converts a physical quantity measured thereby to a signal current and outputs the signal current to a two-wire transmission line. The electric current monitoring device includes an electric current detector inserted in the transmission line for measuring an electric current value of the signal current outputted to the transmission line, and a supply voltage generator inserted in the transmission line for outputting a voltage generated due to the flow of the signal current. The electric current detector is driven by the voltage outputted from the supply voltage generator.

Abstract: A method and system for determining a current flowing through an electrical component are provided. A switch electrically coupled to the electrical component and two voltage sources is activated. The activation of the switch causes current to flow through the electrical component after an amount of time. The amount of time between said activating the switch and the flow of current through the electrical component is determined. The current flowing through the electrical component is measured to determine a measured current value. The measured current value is modified based at least in part on the amount of time between said activating the switch and the flow of current through the electrical component.

Abstract: A power meter having complex quadrature output current and voltage filters provides power measurements in high amplitude and frequency variation and/or high jitter environments without requiring high computational overhead. A pair of filters, one for voltage and one for current each have a response determined by complex non-conjugate poles. The response of the filters is such that only the positive or negative half plane of the complex frequency spectrum is passed and provide complex outputs representing the real and imaginary parts of both the current and voltage. At least one indication of a power delivered to a load is computed from the complex current and voltage outputs, which may be the real and/or reactive power.

Abstract: The invention relates to a method for determining the type of connection of at least two electric devices (5) whereby each device comprises a similar connector arrangement. The aim of the invention is to increase the reliability during the starting up process and during the operation of a system which comprises several electric units (5). According to the invention, a first device (5) modifies the voltage on the connector arrangement (11) and the modified voltage is determined as a first voltage, such that a second device (5) determines a second voltage on at least the connector arrangement (11) and determines whether an electric connection exists or not between the connector arrangements (11) of the devices (5) by comparing the determined comparison of the voltages.

Abstract: An operating state detection technique is provided which makes it possible to accurately detect an abnormality of a high-frequency heating apparatus. An anode current detected by the anode current detection resistor 40 of a magnetron is inputted into the A/D converter terminal of a microcomputer 27 on a control panel circuit board side. The current is subjected to an analog-to-digital conversion to thereby obtain an anode voltage IaDC value. The microcomputer 27 determines an operating state based on a plurality of the anode voltage IaDC values thus read. Further, the microcomputer 27 obtains a summed value of the IaDC values corresponding to one period of the revolution of rotary antennas 68, 69 to thereby determines the operating state of the high-frequency heating apparatus 100 based on the summed value.

Abstract: Low cost millimeter wave imagers using two-dimensional focal plane arrays based on backward tunneling diode (BTD) detectors. Two-dimensional focal arrays of BTD detectors are used as focal plane arrays in imagers. High responsivity of BTD detectors near zero bias results in low noise detectors that alleviate the need for expensive and heat generating low noise amplifiers or Dicke switches in the imager. BTD detectors are installed on a printed circuit board using flip chip packaging technology and horn antennas direct the waves toward the flip chip including the BTD detectors. The assembly of the horn antennas, flip chips, printed circuit board substrate, and interconnects together work as an imaging sensor. Corrugated surfaces of the components prevent re-radiation of the incident waves.

Abstract: A voltage detection device that is connected to a DC circuit to which a DC voltage is applied and that detects the DC voltage applied to the DC circuit comprises a voltage conversion means for outputting a first voltage that increases as the DC voltage increases and a second voltage that decreases as the DC voltage increases, an error detection means for detecting an error for the first voltage and the second voltage based upon the first voltage and the second voltage when the DC voltage is 0, and a voltage calculation means for correcting a difference between the first voltage and the second voltage outputted by the voltage conversion means based upon the error detected by the error detection means and calculating the DC voltage based upon the corrected difference between the first voltage and the second voltage.

Abstract: In order to determine amplitudes of measurement signals originating from an AC power supply and to determine the phase shift (ø) between measurement signals more simply, the measurement signals are processed in measurement signal operation devices to form auxiliary signals each having a constant AC amplitude and to obtain first measurement values (v, a, rssi, rssi1, rssi2), in particular, from amplification factors (v) that are applied to the measurement signal (m, m1, m2). The phase shift between two auxiliary signals (h, h?, h?1, h?2) is further determined as a second measurement value, in particular, by means of the time difference (?t) between the zero passages of the auxiliary signals (h, h?, h?1, h?2).

Abstract: A detector wherein a measuring range can be easily switched without increasing mounting area and manufacturing cost. The detector is provided with an EEPROM (4) wherein a plurality of digital value groups are stored by having digital values indicating gain and offset respectively as one group; an instruction means which adds to the EEPROM (4) an instruction to read one group of digital values from the plurality of groups; DA converters (5A, 5B) for converting the digital values of the gain and the offset read from the instructing means into analog values; and a current sensor (6), which adjusts the gain and the offset by output from the DA converters (5A, 5B) and then outputs the detected results.

Abstract: A system for automatically detecting power supply voltage includes a voltage divider connected to a power supply, an A/D converter connected to the voltage divider, a detection module connected to the A/D converter for comparing a digital signal converted by the A/D converter with a reference signal stored in the detection module, a relay driving circuit connected to the detection module, a relay connected to the relay driving circuit and the power supply respectively, and an outlet coupled to the relay for outputting voltage. If the digital signal matches the reference signal, the detection module controls the relay driving circuit to turn on the relay to output voltage at the outlet. Relevant method for detecting power supply voltage is also provided.

Abstract: A measuring device for measuring an electrical current has an alternating-current converter (6) that possesses a primary inductance and an ohmic secondary resistance (RS) and whose output is connected across a measured-value signal conditioning device to a measurement output for a current measuring signal. The output of the alternating-current converter (6) has an ohmic secondary resistance (RS). An active compensation circuit, which at least partially compensates for the voltage drop caused by a current flow in the secondary resistance (RS) at the primary inductance by applying a voltage at the output of the alternating-current converter (6), is disposed between the output of the alternating-current converter (6) and the measurement output.

Abstract: The invention relates to a method for measuring the output current of a clocked half-bridge circuit (1) in which semiconductor switches (5a, 5b) located in half-bridge sections (2a, 2b) are alternatingly opened or closed in push-pull operation and thereby cause an alternating current in an output current circuit. The current flowing through a first semiconductor switch (5a) is measured. The current flowing through a first semiconductor switch (5a) is transformed inductively into a secondary current. At least two measured-value signals are generated for the secondary current, of which a first measured-value signal corresponds to the secondary current when the first semiconductor switch (5a) is closed, and a second measured-value signal corresponds to the secondary current when the first semiconductor switch (5b) is open. The output current is determined by taking the difference between the first and second measured-value signals FIG. 7.

Abstract: Embodiments of a switching power supply circuit are disclosed wherein the number of times that a switch of the circuit is enabled is counted.

Abstract: A clamp-on current and voltage module for an electrical power monitoring system that monitors characteristics of power distributed through one or more power conductors includes a current transformer having a core divided into at least two parts so that the core can be installed around a power conductor without cutting the conductor. The transformer produces a current signal corresponding to current passing through the power conductor. A pair of clamping elements fit on opposite sides of the conductor, for gripping the conductor. The transformer core parts and the clamping elements have engaging surfaces that prevent relative movement between the CT enclosure and the power conductor in a direction transverse to the axis of the power conductor. A voltage sensor makes electrical contact with the power conductor and produces a voltage signal corresponding to the voltage on the power conductor.

Abstract: This present invention discloses a method for performing an accurate calibration of signal measurement by a light-driving system including an automatic power control (APC) circuit which is pre-calibrated for a signal measurement process. By enlarging at least one measured pad of the APC circuit, multiple grounding paths are established via a plurality of probes of a test instrument. An impedance effect predicted on the contact between the probes and the pad is diminished greatly. A voltage value on the pad can be accurately measured. Thus, a reference voltage value input to a first input of a comparator of the APC circuit can be determined on a basis of a specific condition when a ramping voltage value input to a second input of the comparator is substantially equal to a sum of a predetermined reference voltage value and the voltage value of the pad.

Abstract: A method and apparatus provides improved resolution in an analog signal, relative to the resolution of a digital-to-analog converter producing the signal. In one embodiment, a digital electrical power and energy meter varies a digital input to a digital-to-analog converter such that an average of the output of the digital-to-analog converter indicates a value with greater resolution than the instantaneous resolution of the digital-to-analog converter.

Abstract: A method and system for determining a current flowing through an electrical component are provided. A switch electrically coupled to the electrical component and two voltage sources is activated. The activation of the switch causes current to flow through the electrical component after an amount of time. The amount of time between said activating the switch and the flow of current through the electrical component is determined. The current flowing through the electrical component is measured to determine a measured current value. The measured current value is modified based at least in part on the amount of time between said activating the switch and the flow of current through the electrical component.

Abstract: Some embodiments of a method and apparatus to facilitate battery management using a hall-effect sensor. The apparatus includes a hall-effect sensor and a battery management unit. The hall-effect sensor is disposed near the electrical transmission line to detect an amount of current flowing through the electrical transmission line. The current originates from a direct current power source coupled to the transmission line. The power source management unit is coupled to the hall-effect sensor to process a sensor signal from the hall-effect sensor. The power source management unit also determines the amount of current flowing through the electrical transmission line. Other embodiments are described.

Abstract: A method of sensing current comprises providing a current sensor having a gain resolution; setting the gain resolution of the current sensor to an initial resolution; sensing current flowing through the current sensor; evaluating an amplitude of the current; and changing the gain resolution of the current sensor based on the evaluating.

Abstract: There is provided a switching circuit (50) comprising: a transformer (TR1) including at least one winding (P1, S1, S2); a switching device (FET1) coupled between a source of power (60) and the transformer (TR), the switching device (FETI) being coupled to a driving circuits (100) for periodically driving the switching devices (FET1) into conduction to transfer power from the source (60) to the inductive component (TRi). The circuit (50) further includes: a first monitoring arrangement (115) for determining a measure of a magnetizing current present in the transformer (TR1); a second monitoring arrangement for deriving a measure of hard switching occurring in the switching devices (FETI); and a signal processing arrangement (140, 150, 160, 170, 175) for generating a measure of reflected power being transferred through the transformer (TRI) from the measure of the magnetizing current and the measure of hard switching.

Abstract: A device and an associated method for detecting a voltage level of a battery are disclosed. The device employs an analog-to-digital converter or digital-to-analog converter to accurately detecting the voltage level. In one embodiment, the device includes a digital-to-analog converter, a comparison circuit, and a microprocessor. The digital-to-analog circuit outputs a plurality of reference levels according to a setting signal. The comparison circuit is for comparing the output voltage of the battery with the reference levels and outputting a comparison signal. The microprocessor then determines the voltage level of the battery according to the comparison signal.

Abstract: A current measuring system has an electrical component configured to provide an electrical current representative of a parameter of interest at an output node; and an analog to digital converter having a current input node in electrical communication with the output node of the electrical component.

Abstract: Systems and methods for improved power profiling of embedded applications are presented. These inventions provide the ability to measure the power consumption of an embedded application at the task level as the application is executing on the target hardware. Methods and apparatus are provided to permit such measurements in both real-time and non-real-time.

Abstract: An integrated semiconductor memory, which can be operated in a normal operating state and a test operating state, includes a current pulse circuit with an input terminal for applying an input signal. The current pulse circuit is connected to an output terminal via an interconnect for carrying a current. In the test operating state, the current pulse circuit generates at least one first current pulse with a first, predetermined time duration in a first test cycle and at least one second current pulse with a second, unknown time duration in a subsequent second test cycle. In addition to a first current flowing on the interconnect in the normal operating state, a second current flows on the interconnect during the first test cycle and a third current flows during the second test cycle in the test operating state.

Abstract: Sampling is performed. A strobe signal is generated from a first signal. Multiple sampled signals are sampled using the strobe signal. Each of the multiple sampled signals is synchronous with its own clock reference and each of clock references are asynchronous with respect to each other. Analog-to-digital conversion is performed on each sampled value of each of the multiple sampled signals. For each of the clock references that is not synchronous with the first signal, a phase comparison is performed between the clock reference and the first signal to produce a difference value. The difference value indicates a phase difference between the clock reference and the first signal. Analog-to-digital conversion of the difference value is performed at a frequency determined by the strobe signal.

Abstract: A circuit for detecting if a load supplied with a high frequency AC power source is asymmetrical. The input voltage and a DC blocking voltage are connected to a differential amplifier circuit, and any difference in voltage is signaled. The load voltage and the DC blocking voltage are each reduced, for example, to 10% and 20%, respectively, while keeping them proportional to their respective full values.

Abstract: The present invention relates to a digital meter for use of the current and voltage, including a front end signal processing device, a press button input device, a central processing unit (CPU), an LCD controller, an LCD, and an alarm device. When the signals detected by the front end signal processing device exceed the digital values of the maximum or minimum limit of the signal of the current and voltage set by the press button input device, the LCD controller may drive the LCD having different colors to light. Thus, the informed person may identify the detecting results of the current and voltage according to the different colors of the LCD.

Abstract: An envelope detector for detecting the envelope of an input signal. The envelope detector includes an inverter for inverting the input signal and two offsetting circuits for offsetting the input signal and the inverted input signal so as to align the peaks of the signals with zero volts. The two offset signals are then summed, which results in a signal proportional to the inverted envelope of the input signal.

Abstract: A technique for testing digital-to-analog converters includes providing a set of digital input signals to the digital-to-analog converters and comparing a resulting combined output signal from the digital-to-analog converters to a comparison value. A determination is made as to whether the resulting combined output signal is within a predetermined tolerance defined by the comparison value. An apparatus for testing digital-to-analog converters also is disclosed.

Abstract: Within a body, a sensor member, which has one end supported in a cantilever fashion adjacent a predetermined end of the body and has the other end extending into a space of the body, includes a coil section having a plurality of coil segments that are excitable in a same phase by a predetermined A.C. signal and sequentially arranged along a direction of linear movement of a movable member. The movable member has an inner space to permit entry of the sensor member into the movable member. Inner peripheral wall of the movable member defining the inner space includes a magnetism-responsive substance containing a magnetic or electrically-conductive material.

Abstract: The present invention provides a circuit for detecting if a load being supplied with a high frequency AC power source is asymmetrical. The input voltage and the DC blocking voltage are connected to a differential amplifier circuit, and any difference in voltage is signaled. The load voltage and the DC blocking voltage are each reduced, for example to 10% and 20% respectively, while keeping them proportional to their respective full values.

Abstract: A non-isolated type voltage sensor is provided between a battery of less than 60 V and a circuit having a resistor, an end of which is connected to a wire harness while another end is connected to a reference power supply. The non-isolated type voltage sensor includes voltage dividing circuits, which include plural resistors connected in series such that those resistors are connected to the battery in parallel so as to obtain a voltage proportional to a terminal voltage of the battery and less than the reference voltage at a desired voltage dividing point of the plural resistors, a voltage follower, which receives an input of a voltage from the voltage dividing point of the voltage dividing circuit, and a voltage-current conversion circuit including a FET so as to supply a current proportional to a low impedance output voltage obtained through the voltage follower to the ground through a resistor.

Abstract: Current measurement apparatus and methods are disclosed to measure load DC output current on the secondary side of a high frequency transformer in a switched power supply. Current in the primary side of the transformer is detected with a current transformer, which produces a voltage across a resistance proportional to the primary current in the high frequency transformer. Averaging of the voltage across the resistance is performed during periods of power transfer in the high frequency transformer and held by a capacitor until the next period of power transfer. The held voltage is used to determine the true load DC output current on the secondary side of the high frequency transformer by the turns ratio relationship of the secondary current to the primary current of the high frequency transformer.

Abstract: A universal booster amplifier for a Coriolis flowmeter. The booster amplifier receives drive signals from a flowmeter electronics and extends conditioned drive signals to a driver for flow tubes of flowmeter sensor. The booster amplifier includes phase shift circuitry to provide improved drive signals for flowmeters having curved and straight flow tube geometries. The booster amplifier includes offline switching power circuitry which operates on a plurality of standard AC voltages. The booster amplifier combines environmentally innocuous housing and barrier circuitry to meet numerous regulatory agency safety standards for operating environments including explosive environments and increase the ease of installation and service of the booster amplifier.

Abstract: A method and system of testing integrated circuits (IC) via optical coupling. The optical system includes an optical fiber, fixture and focussing element. In addition, channels are provided in the fixture mounted on the integrated circuit to accommodate the optical system. The fixture acts as a heat sink. As such, one or more photosensitive elements/targets on the integrated circuit are probed using light that is brought to a focus on each target site. The light causes latching of data into the integrated circuit (which is operating under influence of a test program) and formation of a test pattern output from the integrated circuit that is used to confirm proper functioning of the IC.

Abstract: An electric power measuring system and method of simple configuration capable of measuring electric power in correspondence to an arbitrary frequency are provided. The QPSK signal is inputted to the spectrum analyzer. The frequency converter converts the QPSK signal into the IF signal. The A/D converter 16 converts the inputted IF signal into the digital data after the band pass filter removes an aliasing component contained in the IF signal. In the electric power calculating device, FIR filters perform a band limiting process, wherein the digital data is passed through the predetermined receiving filter, and extracting process of extracting an in-phase component I or an orthogonal component Q. The square operation devices square I or Q. The adder 25 adds I2 to Q2. Therefore, the electric power is calculated.

Abstract: Apparatus is described for generating a frequency-sweepable measurement signal and a local signal with a frequency separated from the measurement signal frequency by an intermediate frequency. The measurement signal and a local signal are generated by a simple structure, including a high-frequency variable-frequency signal source, a low-frequency fixed-frequency signal source, a first frequency divider and a second frequency divider. The variable-frequency signal source is a sweepable signal source. The first frequency divider divides an output frequency fa from the variable-frequency signal source by n and outputs a measurement signal with a frequency of fa/n. The signal of the variable-frequency signal source is also applied to the first input of the second frequency divider, and the signal of fixed-frequency signal source, with a frequency of fb, is applied to the second input.

Abstract: The invention relates to an electricity meter with signal channels that are passed to a digital signal processing device and each of which has a multiplexer with downstream analog/digital converter. Voltage signals of an electrical consumer can be connected to a first input of the analog/digital converter of the first signal channel, and current signals of the electrical consumer can be connected to a first input of the analog/digital converter of the second signal channel. In order to allow the meter to be used without any circuit variation both as a four-conductor meter and as a three-conductor meter, one of the voltage signals can be connected to a second input of the analog/digital converter of the first signal channel.