An integrated circuit includes a first bandgap voltage reference sub-circuit configured to provide a first bandgap reference voltage; a second bandgap voltage reference sub-circuit configured to provide a second bandgap reference voltage; a voltage regulator sub-circuit configured to derive a first supply voltage using the first bandgap reference voltage and a second supply voltage using the second bandgap reference voltage; a bandgap comparator sub-circuit configured to derive a first internal voltage and a second internal voltage from the first supply voltage, wherein the first internal voltage decreases at a higher rate than the second internal voltage with respect to a decreasing first supply voltage, wherein the bandgap comparator sub-circuit is configured indicate which of the first and the second internal voltages is larger; and a comparator sub-circuit configured to indicate whether a difference between the first supply voltage and the second supply voltage is larger than a predefined threshold.

The present application provides method and circuit for monitoring a voltage of a power supply, which adopts a divided voltage circuit to obtain a divided voltage from an input voltage of an input power source generated from the power supply, for detecting the input voltage according to the divided voltage by adopting a first detection circuit and a second detection circuit. Also, judging whether the divided voltage is clamped according to a clamp threshold value to determine the first detection circuit or the second detection circuit detecting a detection current and determine another detection circuit detecting the divided voltage. Hereby, the input voltage transmitted from a rectification circuit to the power supply is monitored, and the dependence between the two detection circuits is avoided.

A system for ensuring that electrically powered medical equipment is properly grounded includes a current sensor that senses current flowing within a ground connection conductor (e.g., leakage current) for the medical equipment. The sensor may operate based on induced current. Measured current is converted to a voltage value, and the voltage value is analyzed by a processor to determine whether current is present in the ground connection conductor. If no current is present, the ground connection conductor may be faulty. If current is present, the system can also identify voltage-to-patient fault conditions.

A state detection circuit for detecting whether a state of an input node is floating, grounded, or electrically connected to an external voltage includes: a unidirectional device circuit and a determination circuit. The unidirectional device circuit electrically conducts a test node to a detection node unidirectionally. The detection node is coupled to the input node. The test node, the unidirectional device circuit, the detection node and the input node form a current path. The determination circuit determines a state of the input node according to a voltage level of the detection node. Within a detection stage, the state detection circuit provides a test voltage at the test node. A voltage of the detection node is determined by the input node, the test voltage, and a characteristic of the unidirectional device circuit.

Methods and devices are provide for determining a failure in a potential transformer and identifying a phase of the potential transformer exhibiting failure. The failures may be incipient failures. Detecting the failure may include determining voltage magnitudes and angles; determining phase-errors; determining phase-phase errors; and determining an uncorrelated phase using the phase-phase errors. The devices and methods may provide an alarm or indication of the phase exhibiting the potential transformer failures. Post processing may be performed to optimize the time and amount of provided alarms or indications. The voltage angles and magnitudes may be provided by the potential transformers being monitored.

A method for calculating a cell state includes: acquiring a first knee-point voltage threshold of a cell, a first knee-point electricity corresponding to the first knee-point voltage threshold, a second knee-point voltage threshold of the cell and a second knee-point electricity corresponding to the second knee-point voltage threshold; recording a first charging curve of the cell in real time; obtaining a target knee point according to the first charging curve, the first knee-point voltage threshold, and the second knee-point voltage threshold, and obtaining a target-knee-point electricity according to the first knee-point electricity or the second knee-point electricity; detecting the electricity of the cell until the charging is completed, and obtaining a charged electricity of the cell from the target knee point to the completion of charging; and obtaining the capacity of the cell according to the target-knee-point electricity and the charged electricity.

A battery management apparatus according to the present disclosure includes a voltage measurement circuit to measure a cell voltage of each of a plurality of battery cells; and a control unit to determine the cell voltage of each of the plurality of battery cells and a reference voltage of the plurality of battery cells at a preset time interval during a rest period. The control unit determines a first accumulated change of the cell voltage of each battery cell during the rest period. The control unit determines a second accumulated change of the reference voltage during the rest period. The control unit determines whether each battery cell is defective by comparing the first accumulated change of each battery cell with the second accumulated change.

The invention relates to an operational force support device that is adapted to support a user when operating a lid (10). The invention further relates to a method for adjusting a force (F.sub.H) that has to be applied by a user to operate a lid (10). Furthermore, the invention relates to a computer module adapted to output an amplification factor and/or an armature voltage that is/are used in the method according to the invention.

An apparatus and a method for indicating a status of an electrical cable, in particular in a power system of a vehicle the apparatus being configured to be attached to the electrical cable, the apparatus comprising: voltage measuring means for continuously measuring a voltage level of the electrical cable, at least one light-emitting indicator configured to be visibly attached to the electrical cable, control means for controlling emission of light from the at least one light-emitting indicator based on the measured voltage of the electrical cable. The apparatus is adapted to be powered by a power source other than the electrical cable.

Methods and systems provide an indication that a loose connection and/or fault occurred in a breaker box or other electrical connecting device. The method includes calculating normal resistance for circuits within a breaker box when a current drawing load is present, and monitoring increases in voltage drop of the circuits to detect whether the increase is due to increased current flow or a faulty connection.