An extracorporeal blood treatment apparatus is provided comprising a filtration unit (2) connected to a blood circuit (17) and to a dialysate circuit (32); a control unit (12) is configured for calculating a sodium concentration value for the blood; the estimation of the sodium concentration includes the sub-step of calculating the sodium concentration value as an algebraic sum of a main contribution term based on the isoconductive sodium concentrate and of an offset contribution term based on a concentration of at least a substance in the dialysis fluid chosen in the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate and phosphate.

A power storage apparatus includes a charge and discharge controller. To start a voltage increasing operation in a state where a smoothing capacitor is not charged, the charge and discharge controller supplies a nonrestrictive current to a voltage increasing and decreasing circuit after charging the smoothing capacitor with a restrictive current. When a second direct-current voltage is supplied to a second terminal, the charge and discharge controller charges the smoothing capacitor with an increased voltage by the voltage increasing operation after charging the smoothing capacitor with the restrictive current, reduces a potential difference between the charge voltage in the smoothing capacitor and the second direct-current voltage, and then closes a switch circuit.

A circuit board which includes a circuit that measures an input voltage and an output voltage in a voltage converter that converts the input voltage which is a difference between first and second voltages into the output voltage which is a difference between third and second voltages, may include: first to fourth resistor circuits respectively including first to fourth resistor element groups; a first differential amplifier circuit configured such that the first voltage is inputted via the first resistor element group and the second voltage is inputted via the second resistor element group; and a second differential amplifier circuit configured such that the third voltage is inputted via the third resistor element group and the second voltage is inputted via the fourth resistor element group. The second and fourth resistor element groups may be arranged to be adjacent to each other between the first and third resistor element groups.

Described herein are systems and methods that reduce settling time in amplifier circuits, such as voltage sense amplifiers (VSA) or current sense amplifiers (CSA) circuits, that comprise a feedback path. When the feedback path is interrupted via a switch, a CSA circuit switches to open loop. A sample-and-hold circuit holds the output voltage of the amplifier, such that when a load is connected to the CSA circuit, the open loop settling time, which is shorter than the closed loop settling time, is allowed to pass before the CSA output voltage is measured, thereby, advantageously preventing any potential disturbance present at the CSA output from being fed back to the CSA input.

In one implementation, a circuit can include a reference pin and an operational amplifier that can include an output pin, an inverting input pin and a non-inverting input pin. The inverting input pin can be electrically coupled to the output pin via a first impedance and to the reference pin via a second impedance. The non-inverting input pin can be electrically coupled to the reference pin via a third impedance and can be configured to receive a detection signal. The reference pin can be configured to receive a detection reference signal associated with the detection signal.

A detection apparatus is for detecting interference on signal paths in a differential voltage measuring system with a signal measuring circuit for measuring bioelectric signals with a number of useful signal paths having at least one shield. In an embodiment, the detection apparatus includes at least one analysis unit, connected to the shield and embodied to detect interference in a useful signal path of the voltage measuring system via a signal measured at the shield in the case of interference.

A method for measuring a heat generation distribution in a honeycomb structure includes: applying a voltage to a pair of electrode layers of the honeycomb structure to bring the honeycomb structure to an electrically conductive state; measuring resistance values R.sub.n between two different points on the surface of an outer peripheral wall of the honeycomb structure; estimating a current value I.sub.n flowing between the two points using Kirchhoffs law based on each of the resistance values R.sub.n between the two different points, and calculating a heat value generated for each of the resistance values R.sub.n based on each of the resistance values R.sub.n and the current value I.sub.n; and estimating a heat generation distribution in the honeycomb structure based on both the positions at which each of the resistance values R.sub.n is measured, and the heat value calculated from each of the resistance values R.sub.n, in the honeycomb structure.

A current sensing circuit includes a current detection unit having a first resistance element; a first MOS-transistor and a first constant current source connected between a first output end of the current detection unit and a ground terminal; a second MOS-transistor and a second constant current source connected between a second output end of the current detection unit and the ground terminal; a third MOS-transistor having a source connected to the first output end and a gate connected to a drain of the second MOS-transistor; a second resistance element connected between an output terminal and the ground terminal; and a high withstand-voltage MOS-transistor connected between the third MOS-transistor and the output terminal to receive a predetermined control voltage, wherein the gates of the first and second MOS-transistors are commonly connected, and the gate of the first MOS-transistor is connected to the drain thereof.

A voltage detector comprises an input, a resistor divider circuit having resistors coupled in series with one another between the input and a reference node, and N intermediate nodes joining adjacent pairs of the resistors. The voltage detector has N switches coupled to the respective intermediate nodes, as well as a comparator with an input coupled to the switches, a state machine having an input coupled to the output of the comparator, and a decoder having N decoder outputs coupled to respective control terminals of the N switches.

A method includes obtaining different measurements of voltages across terminals of a field device coupled to an I/O loop. The voltage measurements are associated with corresponding loop currents flowing through the I/O loop. The method also includes identifying a baseline loop resistance measurement of the I/O loop using the voltage measurements and the loop currents. The method further includes obtaining additional measurements of voltages across the terminals of the field device. The additional voltage measurements are associated with additional corresponding loop currents flowing through the I/O loop. The method also includes identifying additional loop resistance measurements of the I/O loop using the additional voltage measurements and the additional loop currents. In addition, the method includes detecting a problem with the I/O loop based on the baseline loop resistance measurement and the additional loop resistance measurements.