Showing papers on "Bridge circuit published in 2012"

Memristor Bridge Synapses

Abstract: In this paper, we propose a memristor bridge circuit consisting of four identical memristors that is able to perform zero, negative, and positive synaptic weightings. Together with three additional transistors, the memristor bridge weighting circuit is able to perform synaptic operation for neural cells. It is compact as both weighting and weight programming are performed in a memristor bridge synapse. It is power efficient, since the operation is based on pulsed input signals. Its input terminals are utilized commonly for applying both weight programming and weight processing signals via time sharing. In this paper, features of the memristor bridge synapses are investigated using the TiO memristor model via simulations.

Systems and methods for auto-calibration of resistive temperature sensors

Abstract: The invention relates to systems and methods for calibrating and using resistance temperature detectors. In one embodiment, the system includes a calibration circuit comprising a resistance temperature detector in a bridge circuit with at least one potentiometer, and a programmable gain amplifier coupled to the bridge circuit. Embodiments of the invention further comprise methods for calibrating the bridge circuit and the programmable gain amplifier for use with the resistance temperature detector and methods for determining the self heating voltage of the bridge circuit.

Second and higher harmonics generation with memristive systems

Abstract: We show that memristive systems can be used very efficiently to generate passively both double and higher frequency harmonics. A technique for maximizing the power conversion efficiency into any given harmonic is developed and applied to a single memristive system and memristive bridge circuits. We find much higher rates of power conversion compared to the standard diode bridge, with the memristive bridge more efficient for second and higher harmonics generation compared to the single memristive system. The memristive bridge circuit optimized for second harmonic generation behaves as a two-quarter-wave rectifier.

Second and higher harmonics generation with memristive systems

Abstract: We show that memristive systems can be used very efficiently to generate passively both double and higher frequency harmonics. A technique for maximizing the power conversion efficiency into any given harmonic is developed and applied to a single memristive system and memristive bridge circuits. We find much higher rates of power conversion compared to the standard diode bridge, with the memristive bridge more efficient for second and higher harmonics generation compared to the single memristive system. The memristive bridge circuit optimized for second harmonic generation behaves as a two-quarter-wave rectifier.

Single-circuit output flyback converter controlled in current mode

Abstract: The invention relates to a single-circuit output flyback converter controlled in a current mode. The single-circuit output flyback converter comprises an alternating current input source, wherein the alternating current input source inputs direct current to a first buffer circuit through an input filter capacitor after passing through a rectifier bridge circuit; the first buffer circuit is connected in parallel to a primary winding of a transformer, the primary winding is connected with the drain electrode of a switching tube, and a secondary winding is respectively connected with an output rectifier diode and the input end of a first absorption circuit and is connected to a control chip through a chip power supply circuit; the output end of the output rectifier diode is connected to a three-terminal voltage-stabilizing circuit through an output filter capacitor after being connected in parallel with the output end of the first absorption circuit; a second buffer circuit is connected in parallel between the source electrode and the drain electrode of the switching tube, and the grid electrode and the source electrode are respectively connected with the control chip through a sampling resistor; the compensation end of the control chip is connected with the output end of an isolating circuit, the input end of the insolating circuit is connected in parallel with the output filter capacitor, and the other input end of the isolating circuit is connected with the three-terminal voltage-stabilizing circuit which outputs voltage-stabilizing direct current; and a second absorption circuit is arranged in the three-terminal voltage-stabilizing circuit.

Surface property inspection device and surface property inspection method

Abstract: To provide a surface property inspection device and surface property inspection method with which the surface treatment condition of treated material such as steel subjected to such surface treatments as shot-peening treatment or heat treatment, nitriding, and the like can be non-destructively and precisely inspected, and which offers a high degree of general purpose application. A surface property inspection device 1 includes an AC power supply, an AC bridge circuit, and a judgment device, and the AC bridge circuit has a variable resistor with a variable split ratio γ, a benchmark detector, and an inspection detector. In variable resistor setting step S 1 , the split ratio γ of a variable resistor is adjusted and set so that the output from the AC bridge circuit is increased; after setting a frequency at which the output from the AC bridge circuit is maximized using a frequency setting step S 2 , in pass/fail judgment step S 4 , a benchmark sample S is brought into contact with the benchmark detector, the sample under inspection M is brought into contact with the inspection detector, and the output from the LPF 33 and the threshold value set in the threshold value setting step S 3 are compared and a pass/fail judgment is made of the surface condition of the sample under inspection M.

Nuclear magnetic resonance detection device and method for advanced detection of water bodies in front

Abstract: The invention relates to a nuclear magnetic resonance detection device and a nuclear magnetic resonance detection method for the advanced detection of a water bodies in the front. In the device, a computer is connected with a system controller, a high-power power supply and a signal acquisition unit by a serial port bus respectively; and the system controller is formed by connecting a bridge circuit driver, a high-power H-shaped transmitting bridge circuit, a resonant capacitor and a transmitting coil. Compared with the prior art, the device can detect important information such as the existence of water-bearing bodies in the front, the water content of the water-bearing bodies and the like accurately and effectively. The occupied area of the coil is reduced effectively by a mode of arranging the coil vertically, so that the device can perform exploration in narrow space. The device can detect the underground geological condition within a certain distance in the front directly and accurately in production fields of coal fields and mines or construction sites of tunnels so as to reduce mine accidents caused by geological disasters such as water burst, mud gushing and the like due to unclear geological conditions in the front or various incidents caused by the geological disasters in the process of tunnel construction.

Ac-to-dc conversion apparatus and related control manner thereof

Abstract: An AC-to-DC conversion apparatus is provided, and which includes a first switch-element, an output capacitor and a bridgeless power-factor-correction (PFC) circuit. The bridgeless PFC circuit is coupled to an AC input, and includes a first inductor, a second inductor and a bridge circuit constructed by second to fifth switch-elements. The first switch-element is connected between bridgeless PFC circuit and the output capacitor. Under such circuit configuration and suitable control manner, the common-mode interference in the provided AC-to-DC conversion apparatus is lowered and thus reducing the power loss.

Pop and click noise reduction

Abstract: Disclosed are advances in the arts with novel and useful electronic circuitry with pop and click noise reduction. A load circuit is connected with a full or single-ended half-H bridge circuit and another circuit mechanism in a configuration by which a signal may be used to selectably bring the load circuit terminals to a selected voltage level when an externally applied signal is not present.

Multifunctional power converter circuit for switching switching-network into different switching states during e.g. charging high-volt battery in electric car, has inductor connected to terminal for providing voltage to another terminal

Abstract: The circuit (40) has a bridge circuit (42) comprising three inductors (44a-44c) that are connected to central nodes (45a-45c) of respective half-bridges (42a-42c). One of the inductors is connected to a direct voltage terminal (18) over a switching-network (46) in a switching state (52) of the switching-network in order to provide direct current (DC) voltage (V18ab) to the voltage terminal based on voltage that is applied to another direct voltage terminal (32) or to provide another DC voltage (V32ab) to the latter voltage terminal based on the voltage applied to the former voltage terminal. An independent claim is also included for a method for operating a power converter circuit.

Hybrid multilevel current conversion circuit topology structure and control method thereof

Abstract: The invention discloses a hybrid multilevel current conversion circuit topology structure, which comprises a direct current bus shared by three phases, an A-phase bridge circuit, a B-phase bridge circuit, a C-phase bridge circuit, an A-phase LC filtering circuit, a B-phase LC filtering circuit and a C-phase LC filtering circuit, wherein a first leading-out terminal of the A-phase bridge circuit, a first leading-out terminal of the B-phase bridge circuit and a first leading-out terminal of the C-phase bridge circuit are connected with a positive direct current bus; a second leading-out terminal of the A-phase bridge circuit, a second leading-out terminal of the B-phase bridge circuit and a second leading-out terminal of the C-phase bridge circuit are connected with a negative direct current bus; third and fourth leading-out terminals of the A-phase bridge circuit are connected with the A-phase LC filtering circuit; third and fourth leading-out terminals of the B-phase bridge circuit are connected with the B-phase LC filtering circuit; and third and fourth leading-out terminals of the C-phase bridge circuit are connected with the C-phase LC filtering circuit. The hybrid multilevel current conversion circuit topology structure can be applied to back-to-back structures and high voltage direct current transmission (HVDC) and flexible alternating current transmission systems (FACTS).

Motor drive control device

Abstract: A motor drive control device is provided in which if any abnormality occurs in a drive control circuit, drive command signals the drive control circuit generates are interrupted at once, so that an AC motor can be stopped in safety. A monitor control circuit and drive command signal interruption circuit are provided to the drive control circuit that takes variable-speed control of the AC motor supplied with power from a DC drive power source via a semiconductor bridge circuit. If any abnormality occurs in the drive control circuit, the drive command signals the drive control circuit generates are interrupted at once. When starting operation, the drive control circuit and monitor control circuit cooperate with each other to conduct preliminary check as to whether or not the drive command signal interruption circuit operates normally, base on a predetermined time schedule, and stop the AC motor without fail if any abnormality occurs during operation.

Memristor bridge circuit for neural synaptic weighting

Abstract: A simple and compact memristor-based bridge circuit which is able to perform signed synaptic weighting in neuron cells is proposed. The proposed memristor-based synapse is composed of four memristors which makes a bridge type configuration. By programming different values on each memristor of the memristor bridge circuit, weighting values can be set on the memristor bridge synapses. Various simulation results are included.

High current range magnetoresistive current sensor

Abstract: A system includes a magnetoresistive (MR) bridge circuit, a magnetic field sensor, and an adjustable load. The MR bridge circuit receives a supply voltage and generates an output voltage that indicates a strength/direction of a magnetic field. The MR bridge circuit includes first and second MR elements connected in series between a supply node and a ground node, and third and fourth MR elements connected in series between the supply node and the ground node. The output voltage is generated between a first node that is common to the first and second MR elements and a second node that is common to the third and fourth MR elements. The sensor generates signals based on the strength/direction of the magnetic field. The adjustable load is connected in parallel with one of the MR elements, and has a resistance that is controlled based on the signals generated by the sensor.

Dc/dc converter with resonant converter stage and buck stage and method of controlling the same

Abstract: A direct current to direct current (DC/DC) converter includes a resonant converter stage, a buck stage, and a processor apparatus. The resonant converter stage includes a bridge circuit. The buck stage is configured to output an output voltage and an output current, is electrically connected in series with the resonant converter stage, and includes a buck switch. The processor apparatus is configured to sense the output voltage and the output current, and, based on the sensed output voltage and the sensed output current, to perform one of: (a) fixing a switching frequency of the bridge circuit to a predetermined maximum switching frequency and controlling the output voltage by controlling a duty cycle of the buck switch, and (b) fixing the duty cycle of the buck switch to a predetermined duty cycle and controlling the output voltage by controlling the switching frequency of the bridge circuit.

Direct current insulation monitoring system and method capable of reducing busbar voltage fluctuation

Abstract: The invention relates to a direct current insulation monitoring system and method capable of reducing busbar voltage fluctuation. The system comprises a balanced bridge circuit and an unbalanced bridge circuit, wherein the balanced bridge circuit comprises a positive balancing resistor to ground and a negative balancing resistor to ground; the unbalanced bridge circuit comprises a negative unbalancing resistor to ground and a positive unbalancing resistor to ground; at least one of the negative unbalancing resistor to ground and the positive unbalancing resistor to ground and the resistance of at least one of the negative unbalancing resistor to ground and the positive unbalancing resistor to ground are controllable and variable; and the resistance can vary continuously or stepwise. When direct current insulation monitoring is carried out, the positive and negative unbalancing resistors to ground are varied continuously or stepwise to measure the positive and negative voltages to ground so as to compute the insulation resistance of positive and negative busbars. Overlarge momentary fluctuation of the positive and negative voltages to ground of the busbars can not be caused when insulation monitoring is carried out by the system and the method.

Bridge circuit for Ethernet powered device

Abstract: A network powered device includes field effect transistors connected as bridge circuit. The bridge circuit includes control circuitry to enable the FETs based on completion of a powered device detection sequence performed by power sourcing equipment coupled to the device via an Ethernet link.

Magnetic position detection device

Abstract: A distortion of a signal of a magnetic position detection device is reduced so that precise position information at a high degree of accuracy can be obtained. The magnetic position detection device 100 includes a magnetic movable body 10 , a bridge circuit 20 , a correction circuit 30 , and a detection circuit 40 . The magnetic movable body 10 is magnetized so that N-poles and S-poles alternately appear and has a region in which distances between the N-poles and the S-poles are constant. The bridge circuit 20 is formed of first, second, third, and fourth field detection portions 2 R 1, 2 R 2, 2 R 3 , and 2 R 4 . The correction circuit 30 is formed of fifth and sixth field detection portions 2 R 5 and 2 R 6 . The detection circuit 40 detects a position of the magnetic movable body 10 on the basis of a differential output Vout of the bridge circuit.

System and method for improving low-load efficiency of high power converters

Abstract: Systems and methods for improving low-load efficiency of power converters are provided. The power converter can include one or more bridge circuits having multiple switching modules, such as insulated gate bipolar transistor (IGBT) modules, connected in parallel within the same bridge circuit. The power converter is configured to convert power from an input power source, such as a photovoltaic array or a wind turbine, into output power at a grid frequency. To avoid excessive switching losses at low load conditions, the power converter can be controlled to selectively operate a subset of the switching modules within the same bridge circuit based on a load condition for the power converter. The remaining switching modules in the bridge circuit can be disabled.

An oscillator based active bridge circuit for converting capacitance change into frequency for capacitive humidity sensor

Abstract: A simple signal conditioning circuit for converting capacitance change into frequency for capacitive humidity sensors is presented. It is based on a relaxation oscillator in which output frequency is linearly related to the capacitive unbalance of an active bridge. The design, analysis, and experimental results of the circuit and its application to a sol gel thin film porous γ-Al 2 O 3 based humidity sensor are reported. Experimental results confirm the theoretical value predicted. The circuit covering wide capacitance measurement range has the potential for remotely monitoring measurement parameters accurately.

Charger for portable electronic device

Abstract: A charger includes a power supply generating a direct current power supply potential, an output transistor, a USB connector, a controller, and a resistor bridge circuit. The controller has a potential setting circuit which sets the potentials of the first and second connection nodes of the resistor bridge circuit to a middle potential between a power supply potential and a ground potential in a first mode, and sets the potentials of the first and second connection nodes to the power supply potential in a second mode.

Variable resistor arrangement, measurement bridge circuit and method for calibrating a measurement bridge circuit

Abstract: A measurement bridge circuit includes a first branch and a second branch. The first branch contains a first resistor which is sensitive to measured variables and an invariable resistor connected in series. A first tap point is located between the first resistor and the invariable resistor. The second branch contains a second resistor which is sensitive to measured variables and a variable resistor arrangement connected in series. The variable resistor arrangement includes a first component having an invariable electrical resistance value and a second component having a variable electrical resistance value. The second component is connected in parallel with the first component in order to vary a total electrical resistance value for the variable resistor arrangement. A second tap point is located between the second resistor and the variable resistor arrangement.

Integrated semiconductor device and a bridge circuit with the integrated semiconductor device

Abstract: A bridge circuit is provided. The bridge circuit includes a first integrated semiconductor device having a high-side switch, a second integrated semiconductor device having a low-side switch electrically connected with the high-side switch, a first level-shifter electrically connected with the high-side switch and integrated in one of the first integrated semiconductor device and the second integrated semiconductor device, and a second level-shifter electrically connected with the low-side switch and integrated in one of the first integrated semiconductor device and the second integrated semiconductor device. Further, an integrated semiconductor device is provided.

Compensation bridge circuit with temperature-dependent voltage divider

Abstract: The bridge circuit with temperature-dependent voltage divider for compensation of cold-junction temperature of thermocouple is described. The proposed circuit allows reducing the influence of cold-junction to less than 0,1С for thermocouples of the K-type (chromel - alumel) and L-type (chromel - copel). Streszczenie. W artykule opisano mostkowy uklad kompensacji wolnych koncow termopary zawierający zalezny od temperatury dzielnik napiecia. Opracowany uklad pozwala zmniejszyc wplyw zmian temperatury wolnych koncow na wynik pomiaru ponizej 0,1С dla termopar typu K (chromel- alumel) i typu L (chromel-kopel). (Mostkowy uklad kompensacji wolnych koncow termopary zawierający zalezny od temperatury dzielnik napiecia)

LINC transmitter with improved efficiency

Abstract: A radio frequency (RF) transmitter is provided. The RF transmitter includes first and second drivers that are configured to receive first and second sets of complementary RF signals. Restoration circuits are coupled to the first and second drivers, and a bridge circuit is coupled to the first and second restoration circuits. By having the restoration circuits and the bridge circuit, a common mode impedance and a differential impedance can be provided, where the common mode impedance is lower than the differential impedance.

Direct current insulation monitoring system and method capable of overcoming relay protection maloperation

Abstract: The invention relates to a direct current insulation monitoring system and method capable of overcoming relay protection maloperation. The system comprises a balanced bridge circuit and an unbalanced bridge circuit, wherein the balanced bridge circuit comprises a positive balancing resistor to ground and a negative balancing resistor to ground; and the unbalanced bridge circuit only comprises a negative unbalancing resistor to ground and a change-over switch of the negative unbalancing resistor to ground. When insulation monitoring is carried out, the insulation resistance of the positive and negative busbars is computed by changing over the unbalanced bridge circuit and measuring the voltages to ground of the positive and negative busbars; and when a relay protection system is subjected to positive grounding, insulation monitoring is carried out at the moment, and relay protection maloperation can not be caused by changing over the unbalanced bridge circuit as the unbalanced bridge circuit only comprises the negative unbalancing resistor to ground and the change-over switch of the negative unbalancing resistor to ground.

Led lighting driving circuit

Abstract: PURPOSE: A light emitting diode drive circuit for illumination is provided to reduce EMI(Electro-Magnetic Interference) or EMC(Electro-Magnetic Compatibility) by reducing switching noise CONSTITUTION: A bridge circuit part(410) outputs positive voltage from Vac voltage A voltage detector(420) determines the size of input voltage The voltage detector controls an upper switch(440) and a lower switch(450) A voltage-current converter(430) generates current proportional to the input voltage The upper switch and the lower switch change a connection state of light emitting diode groups(460)

Magnetoresistive sensor and gradiometer

Abstract: An object of the invention is to reduce 1/f noise and white noise at the same time by integrally reducing noise of an MR sensor and noise of an operation circuit part. A magnetoresistive sensor according to the invention includes a plurality of magnetoresistive sensor parts each having a bridge circuit in which four magnetoresistive elements are connected, and outputs of the respective magnetoresistive sensor parts are connected in parallel to one another to an input of an amplifier circuit (see FIG. 2 ).

Detection device and detection method for wide-range vibration amplitude of blade of aviation engine

Abstract: The invention provides a detection device and a detection method for wide-range vibration amplitude of a blade of an aviation engine. The detection device comprises a power supply, a fixture, bridge circuit boxes, millivoltmeters, a reading microscope, a spiral lifting support and current probes, wherein two transverse fixing supports for fixing the current probes are arranged on the spiral lifting support. An output end of a first current probe is connected with an input end of a first bridge circuit box. An output end of the first bridge circuit box is connected with an input end of a first millivoltmeter. An output end of a second current probe is connected with an input end of a second bridge circuit box. An output end of the second circuit box is connected with an input end of a second millivoltmeter. The power supply is connected with a detected blade which is fixed on the fixture. The detection device and the detection method solve the problem of difficult monitoring of the wide-range vibration amplitude in a blade fatigue test, provide a completely novel test method for monitoring technology of blade and blade tip vibration amplitude in the vibration fatigue test, and expand test technology of vibration stress in the blade fatigue test.