A voltage detecting device detects a differential voltage between two input nodes having a non-zero common mode voltage. A differential voltage detecting circuit 5 detects the differential voltage by sampling each voltage of the input nodes and outputs a detection voltage indicating a detection result. A leak canceling circuit generates a compensating current, which flows in opposition to a leak current flowing out from the input nodes in correspondence to an operation of the differential voltage detecting circuit. An operation control part controls the leak canceling circuit to perform or stop a canceling operation. A failure diagnosing part performs a failure diagnosis about the leak canceling circuit based on a first detection value and a second detection value of the detection voltages, which are detected during periods when the leak canceling circuit performs and stops the canceling operation.

A semiconductor device includes a clock generator which receives an input clock and generates an output clock, a reference voltage generator which receives the input clock or the output clock, generates a sub-reference voltage in accordance with a frequency of the input clock or a frequency of the output clock, and generates a reference voltage using the sub-reference voltage and a preset error voltage, and a clock detector which receives the output clock, generates a first output voltage in accordance with the output clock, and compares the generated first output voltage with the reference voltage to output an error signal based on the output clock, wherein the preset error voltage is set in accordance with a degree of preset error of the output clock.

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.

A setting of a measurement instrument comprises the providing a reference measurement instrument that uses at least one instrument parameter. A training phase is performed for a particular signal type to be processed by said reference measurement instrument in order to retrieve an optimal setting for said at least one instrument parameter. A lookup table is created for said particular signal type, said lookup table comprising at least said optimal setting for said at least one instrument parameter.

Systems and methods may be used to measure a frequency of a power delivery system and/or of a supply signal transmitted to a load. A system may record an input waveform, determine a frequency of the input waveform at a present time based at least in part on the input waveform and a derivative of the input waveform, and control an operation of a power delivery system based at least in part on the determined frequency.

A test and measurement instrument includes an input for accepting an input signal from a Device Under Test (DUT), acquisition memory for storing a sampled waveform derived from the input signal, an output display, and one or more processors configured to accept a portion of the sampled waveform as a search portion, search the sampled waveform for portions similar to the search portion, and visually indicate, on the output display, portions of the sampled waveform that are similar to the search portion as matched portions. Methods of operation and description of storage media, the operation of which performs the above operations, are also described.

A battery type determination system includes an electric circuit connected to a battery, and a battery type determination device that determines a type of the battery on the basis of a characteristic value of the electric circuit. The electric circuit includes an AC power supply having a variable frequency, and a capacitor circuit. The battery type determination device includes a resonance state detection unit that detects at least one resonance state in response to an AC signal output from the AC power supply, a resonance frequency detection unit that detects a resonance frequency in the resonance state, a resonance characteristic detection unit that uses the resonance frequency as a resonance characteristic of the battery, and a determination unit that determines whether or not the battery is of the same type as a reference battery by comparing the resonance characteristic of the battery with a reference resonance characteristic of the reference battery serving as a reference for the battery.

Systems and methods may be used to measure a frequency of a power delivery system and/or of a supply signal transmitted to a load. A system may record an input waveform, determine a frequency of the input waveform at a present time based at least in part on the input waveform and a derivative of the input waveform, and control an operation of a power delivery system based at least in part on the determined frequency.

An environmental frequency sensing device, includes logic that performs signal strength (SS) level separation on a received band of frequencies to produce SS level separated frequencies. The logic performs frequency grouping on the SS level separated frequencies for each signal strength level to produce magnitude information for each grouping. The logic generates peak data by detecting peaks of the produced magnitude information. The logic generates an edge event indicating a signal edge based on arrival or departure of a given peak and compares, on a frequency basis, generated edges to stored fingerprint data of a signal of interest. Based on the comparison, the logic provides detected signal data indicating current use of a range of frequencies in an environment.

A wireless power transfer system and a control method thereof. The wireless power transfer system includes: a transmitter coil configured to be magnetically coupled to a receiver coil; a power conversion device coupled to the transmitter coil; and a controller including a one-half cycle detection block, wherein the one-half cycle detection block is configured to establish a current sensing time instant, and wherein at the current sensing time instant, a current flowing through the transmitter coil is detected and compared to a predetermined threshold to perform foreign object detection to determine whether a foreign object is coupled to the wireless power transfer system.