An autoranging ammeter with fast dynamic response allows improved dynamic measurement of rapidly changing direct electrical currents. The ammeter utilizes a low-cost dual threshold comparator mechanism coupled with an analog-to-digital converter and digital processing to rapidly select the appropriate current shunt resistor.

Disclosed is a current sampling circuit including a proportional current output circuit and a full differential common mode negative feedback circuit, specifically the proportional current output circuit is configured to calculate a current output from a power device according to a preset proportion to obtain a first proportional current and a second proportional current, and to output the first proportional current and the second proportional current to the full differential common mode negative feedback circuit; and the full differential common mode negative feedback circuit is configured to shunt respectively the first proportional current and the second proportional current using a full differential common mode negative feedback network with a bias current in microamps to obtain a first sampling current and a second sampling current, and to output constantly the first sampling current and the second sampling current. Further disclosed is a current sampling method.

A patient care system is configured for infusing fluid to a patient. The system includes a plurality of modular fluid infusion pumps that each has a connector for connecting to a modular programming unit or to one another. Systems and methods are configured for verifying that the connectors are reliably performing their functions or communicatively connecting the pumps to one another or to the programming unit.

A multi-channel digital to analog converter, DAC, comprising: a DAC configured to provide an analog signal comprising a plurality of time division multiplexed sub-signals, each provided for one of a plurality of output channels; wherein each of the output channels include: a sampling capacitor; a selector switch configured to couple the sampling capacitor of the respective output channel to the output terminal of the DAC such that the sampling capacitor samples the analog signal over a plurality of discrete sampling periods; a comparator configured to provide a comparator output signal, wherein the sampling capacitor is coupled to an input terminal of the comparator; and an output control gate configured to control whether or not the comparator output signal is output from the respective output channel at a predetermined time later than a first of the respective plurality of discrete sampling periods.

A digital input and output signal test platform includes a digital input signal circuit, a digital output signal circuit, and a digital signal interface circuit. The digital input signal circuit generates a plurality of digital input signals and displays the generated digital input signals. The digital output signal circuit receives a plurality of digital output signals and displays the received digital output signals. The digital signal interface circuit transmits the generated digital input signals to digital input ports of an electronic product under test, and transmits the digital output signals output from digital output ports of the electronic product to the digital output signal circuit.

A current sensor that outputs an output signal according to a signal magnetic field that is generated by a current to be measured is provided. The current sensor includes at least one magnetic sensor, a temperature sensor, an amplifier, and an offset adjusting circuit. The magnetic sensor generates a sensor signal commensurate with the signal magnetic field. The temperature sensor detects an ambient temperature. The amplifier amplifies the sensor signal at an amplification rate commensurate with the detected temperature and generates the output signal. The offset adjusting circuit adjusts an offset of the output signal. The offset adjusting circuit adjusts an offset in accordance with a relationship (mathematical expression) that holds between an output signal under no signal magnetic field and an amplification rate corresponding to the temperature.

An embodiment circuit comprises high-side and low-side switches arranged between supply and reference nodes, and having an intermediate node. A switching control signal is applied with opposite polarities to the high-side and low-side switches. An inductive load is coupled between the intermediate node and one of the supply and reference nodes. Current sensing circuitry is configured to sample a first value of the load current flowing in one of the high-side and low-side switches before a commutation of the switching control signal, sample a second value of the load current flowing in the other of the high-side and low-side switches after the commutation of the switching control signal, sample a third value of the load current flowing in the other of the high-side and low-side switches after the second sampling, and generate a failure signal as a function of the first, second and third sampled values of the load current.

A multiple operating-mode comparator system can be useful for high bandwidth and low power automated testing. The system can include a gain stage configured to drive a high impedance input of a comparator output stage, wherein the gain stage includes a differential switching stage coupled to an adjustable impedance circuit, and an impedance magnitude characteristic of the adjustable impedance circuit corresponds to a bandwidth characteristic of the gain stage. The comparator output stage can include a buffer circuit coupled to a low impedance comparator output node. The buffer circuit can provide a reference voltage for a switched output signal at the output node in a higher speed mode, and the buffer circuit can provide the switched output signal at the output node in a lower power mode.

A MEMS device may output a signal during operation that may include an in-phase component and a quadrature component. An external signal having a phase that corresponds to the quadrature component may be applied to the MEMS device, such that the MEMS device outputs a signal having a modified in-phase component and a modified quadrature component. A phase error for the MEMS device may be determined based on the modified in-phase component and the modified quadrature component.

The present invention corresponds to a method and an apparatus for detecting faults in transmission and distribution systems. The method is characterized by the steps of: a) Rectifying the ac current signal of the “auxiliary services” triphasic system; b) Rectifying and inverting the ac current signal of the transmission and distribution system; c) Connecting the step b signal to step a signal; d) Measuring the ac current signal obtained in step b; e) Measuring the dc current signal rectified in step a; f) Scaling the value of the current measured in step e by a scale k factor; g) Calculating the rms value of the signal measured in step d; h) Finding the difference between the values obtained in steps f and g; i) Comparing the absolute value of the step h difference with a reference value m; j) If the comparison made in step i is greater than the reference value m, a trigger signal is generated and the tension is maintained between the dc points of step b in about from 0 to 90%, of the operating tension with no fault. The apparatus comprises, a rectifier; an inverter connected to the rectifier; current measuring means at the rectifier and inverter outlets; and a control unit connected with the rectifier, the inverter and the current measuring means that makes the tripping command of the rectifier and the inverter, and compares the dc current measure at the rectifier outlet with the inverter outlet current, sending a tripping signal according to said comparison.