A sensor processing system includes a plurality of reduction circuits. The plurality of reduction circuits correspond to a plurality of sensors on a one-to-one basis. Each of the plurality of reduction circuits is electrically connected to an output terminal of a corresponding one of the plurality of sensors to reduce a low-frequency component of a sensor output of the corresponding one of the plurality of sensors.

A method for measuring frequency domain characteristics of a PDN having an output terminal connected to a power supply end of a functional circuit. The method includes: a to-be-measured output interface of the functional circuit is acquired; the to-be-measured output interface is controlled to output a first level signal having a first preset rule; remaining at least one output interface of the functional circuit, other than the to-be-measured output interface, is controlled to output a second level signal having a second preset rule according to a first frequency; changing voltage values corresponding to the first frequency and output by the to-be-measured output interface are acquired; and a characteristic impedance of the PDN at the first frequency is determined based on the changing voltage values corresponding to the first frequency.

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 frequency detection circuit includes a signal source that outputs a first clock signal and a second clock signal that has the same frequency as the first clock signal and a different phase from the first clock signal, a S/H circuit that undersamples a frequency-detection target signal using the first clock signal output from the signal source and outputs a first sampling signal indicating a result of undersampling, and undersamples the frequency-detection target signal using the second clock signal output from the signal source and outputs a second sampling signal indicating a result of undersampling, and a frequency calculation circuit that calculates a phase difference between the first sampling signal output from the S/H circuit and the second sampling signal output from the S/H circuit and calculates the frequency of the frequency-detection target signal on the basis of the phase difference.

Improved determination of a trigger time. For this purpose, an input signal is provided to multiple low pass filters having different bandwidths. A trigger event is detected in each of the low pass filtered signals and a corresponding trigger time is determined. The trigger time which is determined based on valid trigger detection and provided by the low pass filter with the highest bandwidth is used for further analysis.

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 oscillatory electric signal having an oscillation frequency is processed by time-sampling to generate a sampled oscillatory electric signal. A nonlinear circuit driven by the sampled oscillatory electric signal outputs a hysteretic response signal as a function of the sampled oscillatory electric signal. The hysteretic response signal has a frequency in a first frequency range as a result of an increase in the oscillation frequency of the oscillatory electric signal, and a frequency in a second frequency range as a result of a decrease in the oscillation frequency of the oscillatory electric signal. A detection circuit processes the hysteretic response signal to compute an envelope signal of the hysteretic response signal, perform a comparison of the envelope signal with a threshold, and produce a signal indicative of an increase or a decrease in the oscillation frequency of the oscillatory electric signal as a result of the outcome of the comparison.

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 frequency ratio measurement device includes a counter section configured to count a time event of a first signal and output a count value obtained by multiplying the time event by k.sub.0, a time to digital converter section configured to output a time digital value corresponding to a phase difference between the first signal and a second signal, a combiner section configured to output a combined value of the count value and the time digital value, a subtractor section configured to output a difference value between a first value based on the combined value and a second value, a quantizer section configured to compare a third value based on the difference value with a predetermined threshold to thereby output a quantized value obtained by quantizing the third value, and a feedback section configured to output, based on a time event of the second signal, the second value based on the quantized value. The frequency ratio measurement device outputs, based on the quantized value, a delta-sigma modulated signal corresponding to a frequency ratio of the first signal and the second signal.

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.