A voltage sensor system for sensing voltage in a conductor, the voltage sensor system including a first plate, a first electrode disposed a first distance away from the first plate, a second plate, a second electrode disposed a second distance away from the second plate, a control unit structured to control one of the first plate and the second plate to be grounded and the other of the first plate and the second plate to be electrically floating, and a differential amplifier electrically connected to the first electrode and the second electrode and being structured to output an output voltage that is proportional to a difference in voltage between the first electrode and the second electrode.

A test system for measuring electrical current consumption of a device under test (DUT) includes a capacitor with power and ground terminals; a voltage regulator with input and output terminals; first and second switching elements; and a controller. The voltage regulator generates a DUT operating voltage based on its input voltage. The first switching element is arranged between a direct current (DC) voltage source and the regulator input, and the second switching element is arranged between the DC voltage source and the capacitor. The controller operates the switching elements to charge the capacitor, and to configure the test system for measuring operating current of the DUT using the capacitor as the power source.

A fast algorithm is used to study the transient behavior due to the step-like pulse. This algorithm consists of two parts: The algorithm I reduces the computational complexity to T.sup.0N.sup.3 for large systems as long as T<N; The algorithm II employs the fast multipole technique and achieves scaling T.sup.0N.sup.3whenever T<N.sup.2 beyond which it becomes T log.sub.2 N for even longer time. Hence it is of order O(1) if T<N.sup.2. Benchmark calculation has been done on graphene nanoribbons with N=10.sup.4 and T=10.sup.8. This new algorithm allows many large scale transient problems to be solved, including magnetic tunneling junctions and ferroelectric tunneling junctions that could not be achieved before.

The present invention provides a distribution board having a main breaker and a plurality of branch breakers, the distribution board being wired to branch power supplied to the main breaker into each branch breaker, the distribution board including: a plurality of noise detection sections configured to correspond to the respective branch breakers one-to-one and each configured to output a detection signal based on a noise component of not less than a predetermined frequency generated on a secondary side of each branch breaker; and processor configured to separately receive the detection signal output from each noise detection section and determine whether the detection signal is high frequency noise at a threshold or more.

A device having an impedance measurement circuit that allows for reduction of flicker noise can be implemented in a variety of applications. A carrier suppression technique can be implemented that substantially removes the carrier signal with removal of noise artifacts associated with the carrier signal from sidebands of the carrier signal. Carrier suppression in an AC impedance measurement circuit can be implemented by sensing a carrier signal of the measurement circuit at a transmit location of the measurement circuit and subtracting a weighted version of the carrier signal at a receive location of the measurement circuit. One or more compensation impedances can be used such that the sidebands of the carrier signal are received with the carrier signal suppressed with respect to the receive location.

A noise removing circuit may include: a reference voltage control circuit configured to perform a noise detection sequence operation based on noise detection sequence information, and control a reference voltage based on a counting value; a noise detection circuit configured to compare a supply voltage and the reference voltage, and generate a counting value corresponding to noise which has occurred in the supply voltage; a noise calculation circuit configured to generate a loading control signal corresponding to the noise by performing an operation on the counting value and the reference voltage; and a loading control circuit configured to control a loading value for the supply voltage based on the loading control signal.

Methods and apparatus for measuring current are provided. In one arrangement, a first charge amplifier integrates a current to be measured. A processing circuit filters an output from the first charge amplifier using a first low pass filter module and a second low pass filter module. A second charge amplifier integrates a current derived from the filtered output from the first charge amplifier. The apparatus is configured to reset the first charge amplifier at the start of each of a plurality of sensing frames. The processing circuit obtains at least a first sample of the output from the first charge amplifier in each sensing frame. The sampling of the first sample alternates from one sensing frame to the next sensing frame between sampling via the first low pass filter module and sampling via the second low pass filter module.

A method includes providing, by a signal source circuit of a sensing circuit, a signal to a sensor via a conductor. When the sensor is exposed to a condition and is receiving the signal, an electrical characteristic of the sensor affects the signal. The signal includes at least one of: a direct current (DC) component and an oscillating component. When the sensing circuit is in a noisy environment, transient noise couples with the signal to produce a noisy signal. The method further includes comparing, by a transient circuit of the sensing circuit, the noisy signal with a representation of the noisy signal. When the noisy signal compares unfavorably with the representation of the noisy signal, supplying, by the transient circuit, a compensation signal to the conductor. A level of the compensation signal corresponds to a level at which the noisy signal compares unfavorably with the representation of the noisy signal.

A current sensor is configured to detect a current flowing through an electrical conductor. The current sensor includes a core and a coil wound around the core. The core has a hollow configure to allow the electrical conductor to pass through the hollow. The core substantially has a C-shape haying a gap connected to the hollow. At least a part of the gap of the core is located inside the coil. This current sensor suppresses the influence of external noise.

Systems and methods herein provide for sinusoidal signal distortion monitoring and visualization via a Circular Trajectory Approach (CTA). In one embodiment, a system includes a differentiator operable to differentiate an input signal from a sinusoidal signal at substantially a same fundamental frequency of the input signal. The input signal comprising a sinusoidal waveform having distortions. The system also includes a processor operable to calculate a distance index from the input signal to a derivative of the input signal to reveal distortions in the input signal, and a display operable to display the distortions in the input signal.