Patent classifications
G01R15/146
CURRENT SENSOR
A current sensor for a detection target current using a shunt resistor includes: a resistance value correction circuit having a correction resistor; a signal application unit that applies an alternating current signal to a series circuit of the shunt resistor and the correction resistor; a voltage detection unit that detects terminal voltages of the shunt resistor and the correction resistor; and a correction unit that calculates a resistance value of the shunt resistor and corrects the resistance value for detection; and a power supply circuit having a first power supply generation unit that generates a first power supply of the signal application unit from an input power supply of an outside; and a second power supply generation unit that generates a second power supply of the voltage detection unit.
CURRENT SENSOR
A current sensor for detecting a current based on a terminal voltage and a resistance value of a shunt resistor, includes: a resistance value correction circuit having: correction resistors; a signal application unit; a voltage detection unit that detects terminal voltages of the shunt resistor and a part of the correction resistors in a first period, and terminal voltages of all of the correction resistors in a second period; and a correction unit that corrects the resistance value for current detection based on a calculated resistance value of the shunt resistor. Resistance values and resistance accuracies of the correction resistors are higher as the plurality of correction resistors are disposed farther from the shunt resistor.
CURRENT SENSOR
A current sensor of a detection target current using a shunt resistor includes: a resistance value correction circuit having: a correction resistor; a signal application unit that applies an alternating current signal to a series circuit of the shunt resistor and the correction resistor; a first voltage detection unit that detects the terminal voltage of the shunt resistor; a second voltage detection unit that detects a terminal voltage of the correction resistor; and a correction unit that calculates the resistance value of the shunt resistor based on a first voltage detection value by the first voltage detection unit and a second voltage detection value by the second voltage detection unit, and corrects the resistance value for current detection based on a calculated resistance value of the shunt resistor.
CURRENT SENSING CIRCUIT
In accordance with an embodiment, a method of measuring a load current flowing through a current measurement resistor coupled between a source node and a load node includes: measuring a first voltage across a replica resistor when a first end of the replica resistor is coupled to the source node and a second end of the replica resistor is coupled to a reference current source; measuring a second voltage across the replica resistor when the second end of the replica resistor is coupled to the source node and the first end of the replica resistor is coupled to the reference current source; measure a third voltage across the current sensing resistor; and calculating a corrected current measurement of the load current based on the measured first voltage, the measured second voltage and the measured third voltage.
Resistive material, resistor, and manufacturing method of resistive material
A resistive material for sensing current contains particles having an electrically insulating property and a metal body having a three-dimensional network enclosing the particles, and a ratio of the metal body to the whole of the resistive material is 30 vol % or more and 80 vol % or less.
LIGHT STRIP COMMUNICATION SYSTEM
A communication system that utilizes a light strip to carry data using the power and ground connections of the light strip. When used in the context of a truck and trailer, the system may include a sensor node configured to obtain status information about trailer components, and a data hub for collecting the information. The data about the trailer components may be transferred from the sensor node to the data hub using the power and/or ground connections of the light strip. The sensor node may communicate using the light strip by changing the current level of the light strip power connection, and these changes in the current level may be used by the data hub as a signal by which the data may be received.
RESISTOR ARRANGEMENT
A resistor arrangement for measuring current strength having connection elements and a resistor element between the connection elements. The connection elements and the resistor element are arranged in a plane and in a row such that the arrangement is strip-shaped and has its smallest spatial extent perpendicular to the current direction. The resistor element has two contact sides and the connection elements each have a contact face connected to the contact sides. When current flows through the arrangement, current flow lines are formed which are deflected at at least one of the contact sides by an angle of at least 5° at the transition from the connection element to the resistor element.
CURRENT SENSING CIRCUIT AND CORRESPONDING DC-DC CONVERTER
A power switch current sensing circuit includes matching first and second transistors having sources connected to first and second terminals, respectively, of the power switch. A current mirror has a first node coupled to a drain of the first transistor and a second node coupled to a drain of the second transistor. The current mirror sinks a current from the first node equal to a current flowing through the second transistor. A biasing circuit provides a same biasing voltage to the control terminals of the first and second transistors. An output resistance is coupled between the first node and a reference voltage node. A difference between a current flowing through the first transistor and the current sunk by the current mirror circuit from the first node flows through the output resistance. An output voltage produced at the first node is indicative of the current flowing through the power switch.
Inverter and method for measuring phase currents in an electric machine
A three-phase load is powered by a PWM (e.g., SVPWM) driven DC-AC inverter having a single shunt-topology. A shunt voltage and a branch voltage of the inverter (across a transistor to be calibrated) are measured during a second period of each SVPWM sector, and the drain-to-source resistance of the calibrated transistor is calculated. During the fourth period of each SVPWM sector, the branch voltage is measured again, and another branch voltage across another transistor is measured. Using the drain-to-source resistance of the calibrated transistor and the voltage across the calibrated transistor measured during the fourth period, the phase current through the calibrated transistor is calculated. Using the other branch voltage measured during the fourth period and the drain-to-source resistance of its corresponding transistor (known from a prior SVPWM sector), the phase current through that transistor is calculated. From the two calculated phase currents, the other phase current can be calculated.
CURRENT DETECTION DEVICE
A current detection device (30) includes a resistance element (5), and a pair of electrodes (6, 7). The current detection device (30) has a projecting portion (11). The projecting portion (11) has a portion of the resistance element (5) and portions of the pair of electrodes (6, 7). The electrodes (6, 7) have first wall portions (66b, 67b) forming a portion of the projecting portion (11), and second wall portions (66a, 67a) forming the portion of the projecting portion (11). The electrodes (6, 7) have detection areas (66, 67) demarcated by the first wall portion (66b, 67b), the second wall portion (66a, 67a), a leading end portion (66c, 67c), and a contact surface (6a, 7a). The electrodes (6, 7) have voltage detecting portions (20, 21). The voltage detecting portions (20, 21) are arranged in the detection areas (66, 67) with a gap between the leading end portions (66c, 67c).