Abstract: The present disclosure belongs to the field of geological exploration, and particularly relates to a seismic acquisition system based on a frequency domain expansion MEMS sensor, aiming at solving the problem that vibration frequencies exceed the frequency range of the MEMS sensor due to strong vibrations and cross coupling of multi-frequency signals usually occurring in well logging while drilling. When the MEMS sensor suffers strong vibrations or the MEMS sensor that can be selected cannot ensure that the frequency requirement of a measurement signal is stably met, the frequency domain expander of the present disclosure expands the frequency domain of a detection signal, so that the MEMS sensor can measure strong vibrations and out-of-band frequencies to a certain extent, the application range of the seismic acquisition system is extended, and the anti-mutation capability of the seismic acquisition system is improved.

Abstract: An analog front-end circuit capable of dynamically adjusting gain includes a programmable gain amplifier (PGA) circuit, a sensor, a calculation circuit, a gain coarse control circuit and a gain fine control circuit. The PGA circuit includes an amplifier, a gain coarse adjustment circuit and a gain fine adjustment circuit. The gain coarse adjustment circuit is controlled by a coarse control signal, and a gain is adjusted in a coarse step according to an initial gain. The gain fine adjustment circuit is controlled by a fine control signal in a data mode, and the gain is adjusted in a fine step. The calculation circuit calculates a primary gain adjustment and a secondary gain adjustment. The gain coarse control circuit generates the coarse control signal according to the primary gain adjustment, and the gain fine control circuit generates the fine control signal according to the secondary gain adjustment.

Abstract: In general, an X-ray imaging apparatus according to one embodiment includes an X-ray tube, an X-ray detector, and processing circuitry. The processing circuitry is configured to obtain correction-target data that includes component deterioration resulting from a transient response of the X-ray detector, and to output, based on the obtained correction-target and a model that outputs data in which component deterioration resulting from a transient response is reduced based on an input of data that includes component deterioration resulting from a transient response, corrected data in which the component deterioration resulting from the transient response of the X-ray detector is reduced.

Abstract: An on-off keying (OOK) receiver circuit includes a band-pass filter and an envelope detector. The band-pass filter includes a high-pass filter, a low-pass filter, and a switch. The high-pass filter is configured to filter an OOK input signal. The low-pass filter is configured to filter an output signal of the high-pass filter. The switch is coupled to an output of the high-pass filter, and is configured to, with each cycle of the OOK input signal, dissipate energy stored in the band-pass filter. The envelope detector is configured to receive a filtered OOK input signal from the band-pass filter, and to generate an OOK output signal based on the filtered OOK input signal.

Abstract: A high-voltage circuit has a protection circuit protecting a low-voltage MOSFET. A first MOSFET, a low-voltage device with a gate coupled to an input voltage, is coupled in a series with a second MOSFET which is a high-voltage device, both of a first conductivity type. A protection circuit includes a third, a fourth, and a fifth MOSFET. The third MOSFET has a second conductivity type and source and body coupled to the input voltage. The fourth MOSFET has the first conductivity type and a drain coupled to a drain of the third MOSFET, a gate coupled to a second bias voltage, and a source and a body coupled to the first power terminal. The fifth MOSFET has the first conductivity type and a drain coupled to the input voltage, a gate coupled to the drain of the fourth MOSFET, and a source coupled to the first power terminal.

Abstract: A method of obtaining an absolute time reference for a high-frequency (HF) sounding signal includes transmitting a reference signal at a first location and transmitting a sounding signal in close proximity to the transmitting of the reference signal at the first location. The method additionally includes receiving the reference signal at a second location and receiving the sounding signal at the second location. The method further includes determining a relative delay at the second location of the sounding signal in relation to the reference signal. The method also includes determining a propagation mode based upon the relative delay. The method additionally includes determining an absolute time reference based upon the propagation mode being observed. Additional methods and associated systems for implementing the methods are also provided.

Abstract: Provided is a method and apparatus for measuring a biosignal. The biosignal measurement method may include measuring, at a biosignal measurement apparatus, a biosignal using a biosignal measurement sensor; processing, at the biosignal measurement apparatus, the biosignal and converting the biosignal to a pulse signal using a first voltage distribution time constant circuit and a waveform converter; and counting, at the biosignal measurement apparatus, the pulse signal using a counter and generating first biometric information. The first voltage distribution time constant circuit may filter a signal of a specific frequency band from the biosignal based on voltage distribution using a series resistance included in the first voltage distribution time constant circuit.

Abstract: The present invention breaks up the frequency bands which can be filtered by a simple low-loss band-pass or low pass filter. The second harmonic frequency is reduced by use of a non-linear clipper element which controls the driving waveform symmetry and can reduce the harmonics by as much as 5-15 db which makes the filter much simpler and allows the amplifier to remain wide-band. The output waveform from the amplifier is symmetrical or nearly symmetrical.

Abstract: A radiation detector is provided that includes a photodiode having a radiation absorber with a graded multilayer structure. Each layer of the absorber is formed from a semiconductor material, such as HgCdTe. A first of the layers is formed to have a first predetermined wavelength cutoff. A second of the layers is disposed over the first layer and beneath the first surface of the absorber through which radiation is received. The second layer has a graded composition structure of the semiconductor material such that the wavelength cutoff of the second layer varies from a second predetermined wavelength cutoff to the first predetermined wavelength cutoff such that the second layer has a progressively smaller bandgap than the first bandgap of the first layer. The graded multilayer radiation absorber structure enables carriers to flow toward a conductor that is used for measuring the radiation being sensed by the radiation absorber.

Abstract: A radio frequency communication system and a noise isolation method applied to the radio frequency communication system are provided. The radio frequency communication system includes an antenna, an amplifier and a noise isolating unit. The amplifier is electrically connected to the antenna to amplify a common-mode signal transmitted by the antenna and outputs an amplified common-mode signal. The noise isolating unit is electrically connected to the amplifier to isolate the amplified common-mode signal. The noise isolating unit includes a first transformer and a second transformer. The noise isolating unit isolates the common-mode signal and transmits the differential-mode signal, which can effectively reduce the noise and improve a signal to noise ratio without affecting the original signal.

Abstract: Various embodiments of systems and methods for reducing audio noise are disclosed. One or more sound components such as noise and network tone can be detected based on power spectrum obtained from a time-domain signal. Results of such detection can be used to make decisions in determination of an adjustment spectrum that can be applied to the power spectrum. The adjusted spectrum can be transformed back into a time-domain signal that substantially removes undesirable noise(s) and/or accounts for known sound components such as the network tone.

Abstract: A clock generation circuit 10 includes a resonant reactor connected with a half voltage supply point TV1, a resonant capacitor CL connected between a ground voltage supply point TVss and an output terminal TVout, a transistor MPconnected between the resonant reactor Lr and the resonant capacitor CL, and a transistor MN1 connected with the output terminal TVout. In this configuration, signals in a wide range of frequencies can be output with low power consumption by adjusting the time when a clock signal ?1 applied to the gates of the transistors MP1 and MN1 is high.

Abstract: A rechargeable multipurpose power management system has a power management system that can include a plurality of power management units. The power management units sources can be individually activated and deactivated (I think there might be a confusion between power sources and the system. Everything is within one box itself (the image that I sent you). Each unit is a power management system that can be connected to a variety of INPUT power sources. Several power management units can be combined together to create a stack of them but each one can operated individually as well). and each one is configured to be coupled to a variety of inputs. A rechargeable battery is coupled to the (One rechargeable battery is attached to only one power management units). A charging controller provides regulated charging to the battery. A plurality of convertors are (do we need to specify here what kind of converters, like DC-DC converters) coupled to the battery and provide output voltages that are accessible individually.

Abstract: RF communications circuitry includes a first RF filter structure, which is disclosed. The first RF filter structure includes a first passive group of RF resonators and active loss-reduction circuitry. The active loss-reduction circuitry is coupled to the first passive group of RF resonators. The active loss-reduction circuitry uses self-limiting positive feedback to reduce signal loss in the first passive group of RF resonators. Additionally, the active loss-reduction circuitry limits the self-limiting positive feedback to prevent self-oscillation in the active loss-reduction circuitry.

Abstract: An electronic device includes an adjustable filter with a first filter element, and a second filter element coupled to the first filter element. The second filter element includes a field effect transistor (FET) including a source terminal, a drain terminal, and a gate terminal. The source terminal and the gate terminal are coupled to a reference voltage. A control circuit is coupled to the drain terminal and is configured to apply a control voltage thereto to vary a capacitance between the source and drain terminals to adjust the adjustable filter.

Abstract: Device for correction of the passband of an air gap transformer with a cut-off frequency, characterised in that it includes a filter adapted to be connected to the transformer in series, and in that the filter is adapted to amplify the signal that it receives from the transformer for frequencies below the cut-off frequency of the transformer, so that the passband of the transformer fitted with the correction device is increased and has a cut-off frequency lower than the cut-off frequency of the transformer.

Abstract: The optimal low power complex filter, as a second order complex filter, is based on current amplifiers (CAs) and is utilized to implement a 4th order current-mode filter that can be used for intermediate frequency (IF) applications, such as, for example, low-IF Bluetooth receivers. Fabricated in a standard 0.18 ?m CMOS technology, experimental results show that the present design offers improved characteristics over the existing solutions in terms of power consumption and spurious-free dynamic range (SFDR). The 4th order filter exhibits in-band SFDR of 65.8 dB while consuming only 1 mW.

Abstract: A tunable filter device includes a first tunable filter with a first pass band, and a second tunable filter connected to the first tunable filter and having a second pass band located within the first pass band and a band width narrower than the band width of the first pass band. The second tunable filter includes a local oscillator that generates a predetermined frequency signal, a mixer that outputs a sum of and a difference between an output signal of the first tunable filter and the predetermined frequency signal output from the local oscillator, and an IF tunable filter connected to the mixer.

Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.

Abstract: A frequency translating analog-to-digital converter for receiving an analog band-pass signal is described. The analog-to-digital converter comprises an adder/input block for receiving the analog band-pass signal and an analog band-pass feedback signal, thereby forming an analog band-pass error signal. The analog-to-digital converter has at least one analog mixer for mixing and down converting the analog band-pass error signal and thus generating a down-converted analog error signal and at least one quantization path for generating at least one digital signal.

Abstract: A filtering device, applicable in a transceiver, includes: a capacitive circuit coupled to an amplifying circuit by a first capacitive configuration or by a second capacitive configuration; and a resistive circuit coupled to the amplifying circuit by a first resistive configuration or by a second resistive configuration; wherein when the capacitive circuit is the first capacitive configuration, the filtering device is used to perform a first filtering process upon a receiving signal of the filtering device, and when the capacitive circuit is the second capacitive configuration, the filtering device is used to perform a second filtering process upon a transmitting signal of the filtering device.

Abstract: A method for removing noise from an electrical signal in an alarm system using a software filter, the method including the steps of converting the electrical signal from an analog signal into a digital signal, wherein the digital signal includes a series of sampled values, entering a most recent of the sampled values into a circular index containing a number of previously sampled values, multiplying each of the values in the circular index by a predetermined filter coefficient, and summing products of each of the multiplied circular index values and filter coefficients to arrive at a filtered digital signal value.

Abstract: An integrated receiver includes a first signal processing path, a second signal processing path, and a controller. The first signal processing path has an input and an output for providing a first processed signal, and comprises a first tracking bandpass filter having a first integrated inductor formed with windings in a first number of metal layers of the integrated receiver. The second signal processing path has an input and an output for providing a second processed signal, and comprises a second tracking bandpass filter having a second integrated inductor formed with windings in a second number of metal layers of the integrated receiver. The second number of windings is lower than the first number. The controller enables one of the first and second signal processing paths corresponding to a selected channel of a radio frequency (RF) input signal to provide an output signal.

Abstract: A receiver includes an antenna interface, a frequency translation bandpass filter (FTBPF), a sample and hold module, and a down conversion module. The antenna interface is operable to receive a received wireless signal from an antenna structure and to isolate the received wireless signal from another wireless signal. The FTBPF is operable to filter the received wireless signal to produce an inbound wireless signal. The sample and hold module is operable to sample and hold the inbound wireless signal in accordance with an S&H clock signal to produce a frequency domain sample pulse train. The down conversion module is operable to convert the frequency domain sample pulse train into an inbound baseband signal.

Abstract: An RF signal reception device including: a transposition device of signals of frequency fRF to a first intermediate frequency IF1<fRF; a first bandpass filter centered on IF1; a sampler at a frequency fs<IF1; a second discrete-time filter centered on a second intermediate frequency IF2=?·fs/M+fs/(M·n); a decimation device of a factor M; an analog-digital convertor to operate at a frequency fs/M; where ?, n and M are strictly positive real numbers chosen such that: ?<fs/(2·BWch·M), and BWch/2<fs/M·n), with BWch: bandwidth of a channel of the received RF signals.

Abstract: A method that includes identifying a desired signal connectivity through a switch matrix, where the switch matrix includes a plurality of switching elements, and where the switching elements are selectively operable in a plurality of states to provide a plurality of signal paths for routing signals through the switch matrix. The method also includes identifying a sorting network model that corresponds to a topology of the switch matrix, applying a sorting algorithm to the sorting network model, and determining, based on the results of applying the sorting algorithm, operational states of the plurality of switching elements to provide signal paths corresponding to the desired signal connectivity.

Abstract: A circuit and method for filtering a signal. An amplifier receives an input signal and generates a differential output signal. A first resonator having series and parallel resonant frequencies is connected to the positive output port of the amplifier. A second resonator having series and parallel resonant frequencies is connected to the negative output port of the amplifier. The first and second resonators are coupled at a connection point. A buffering device receives the combined outputs of the resonators and outputs a filtered signal. The filtering method receives signals and passes them through the elements of the filter circuit to generate a filtered output signal.

Abstract: A band pass filter has a high pass filter into which an input signal is input; an amplifier having an inverting input terminal into which an output of the high pass filter is input, wherein the amplifier amplifies an input voltage between the inverting input terminal and a non-inverting input terminal and outputs an output signal to an output terminal; a first resistor connected between a non-inverting output terminal and the inverting input terminal of the amplifier; a first capacitor having a first terminal that is connected to the inverting input terminal; and an inverting amplifier that inverts a polarity of an output signal from the non-inverting output terminal of the amplifier and outputs the inverted signal to a second terminal of the capacitor.

Abstract: A filter network having a variable cut-off frequency can be controlled in a way that allows the cut-off frequency to be changed gradually to avoid undesirable transient effects. An impedance network (such as a resistor network) that provides a plurality of impedance values is provided. Logic, and a corresponding method, are provided to change the impedance value gradually, such as on a step-wise basis, to change the cut-off frequency gradually. The size of the impedance step and the duration of the step can be preprogrammed, and may be different for different types of events that trigger the need for a frequency change. It may also be possible for those preprogrammed values to be initial values only, with the values changing under programmed control during the frequency changing process. Other values, such as the initial and target impedance values that determine the initial and target frequency, also may be programmable.

Abstract: An acquired signal indicative of electrophysiological activity is filtered using both a wavelet filter and either a notch filter or a band-pass filter to eliminate noise or interference, such as power line interference. A wavelet transform is used to transform the acquired signal into the wavelet domain, where a wavelet filter is applied to extract a soft component (e.g., a component with small wavelet coefficients). A filter, such as a notch filter or a band-pass filter, is applied to the soft component in order to isolate an interference signal. The interference signal is used to produce an output signal representing the acquired signal filtered to eliminate the interference signal. For example, the interference signal may be subtracted from the acquired signal. Alternatively, the output signal may be reconstructed from respective hard and soft components of the acquired signal as transformed into the wavelet domain.

Abstract: An electronic device includes an adjustable filter with a first filter element, and a second filter element coupled to the first filter element. The second filter element includes a field effect transistor (FET) including a source terminal, a drain terminal, and a gate terminal. The source terminal and the gate terminal are coupled to a reference voltage. A control circuit is coupled to the drain terminal and is configured to apply a control voltage thereto to vary a capacitance between the source and drain terminals to adjust the adjustable filter.

Abstract: Some embodiments relate to a band-pass filter arranged in a ladder-like structure. The band-pass filter includes respective inductor-capacitor (LC) resonators arranged on respective rungs of the ladder-like structure. Respective matching circuits are arranged on a leg of the ladder-like structure between neighboring rungs.

Abstract: Some embodiments relate to a band-pass filter arranged in a ladder-like structure. The band-pass filter includes respective inductor-capacitor (LC) resonators arranged on respective rungs of the ladder-like structure. Respective matching circuits are arranged on a leg of the ladder-like structure between neighboring rungs.

Abstract: A transconductance adjustment circuit includes a reference signal generation circuit that outputs a first signal and a second signal that is different by 90 degrees in phase from the first signal, a replica circuit to which the first signal and the second signal are input and which generates a first output signal and a second output signal, and an adjustment signal generation circuit that outputs a transconductance adjustment signal with respect to the adjustment-targeted circuit and the replica circuit. The reference signal generation circuit generates the first signal and the second signal that change in voltage at between a first voltage level and a second voltage level, based on a clock signal, and outputs the generated first and second signals with respect to the replica circuit.

Abstract: A The present invention relates to a phase matching band-pass filter using exponential function approximation, comprising an inductor including a parasitic resistor, a first device wherein a first amplifier is connected in a feedback mode, a capacitor including a parasitic resistor, a plurality of filter devices including a second device that is connected with a second amplifier in a feedback mode, and a coupling capacitor that connects the plurality of filter devices; the impedance of the first device has an increasing exponential function relation with a frequency, impedance of the second device has a decreasing exponential function relation with the frequency, and the first device is connected with the second device in parallel. According to the phase matching band-pass filter using exponential function approximation of this invention, conventional inductors and capacitors can be used 0 without modification or use of negative resistance, resulting in a high-performance phase matching band-pass filter.

Abstract: Embodiments provide methods, devices, circuitry and systems for supporting or implementing functionality to provide a filtering circuit, and for providing a transmitter, receiver or transceiver incorporating the same. One embodiment provides a circuit for filtering signals. The circuit outputs a plurality of signals at a plurality of frequencies, each of the signals being attenuated by an amount determined by the frequency of the signal. The circuit attenuates signals output at a first frequency by an amount which is low relative to the attenuation of signals output at frequencies other than the first frequency. The circuit further attenuates signals output at a second frequency by an amount which is high relative to the attenuation of signals output at frequencies other than the second frequency. Responsive to a change in the control signal, the circuit changes the first and second frequencies while maintaining a fixed ratio between the first and second frequencies.

Abstract: A lossless inductor current sense technique integrates a matched, tunable complimentary filter with a switch mode power supply (SMPS) controller for accurately measuring current through the power inductor of the SMPS without introducing losses in the power circuit. The complimentary filter can be adjusted in-circuit to significantly reduce the effects of component tolerances, accurately measuring the power inductor current for over current protection and/or closed loop control. The frequency pole and gain of the complimentary integrated filter can be adjusted on the fly in order to adapt to dynamically changing operating conditions of the SMPS system.

Abstract: The device described herein proposes an electronic active filter void of capacitors and inductors. The circuit utilizes only operational amplifiers (OP-Amp) and resistors, hence the name Op-R. Although capable of being constructed of lumped circuit elements this filter is intended for integrated circuit (IC) applications. Filtering of signals can be accommodated from dc through the UHF frequency range depending on the selected op-amp ICs. Low pass, band pass, high pass, as well as band reject frequency responses are achievable. Although the circuits described herein are single input-single output, multiple inputs and outputs present no difficulty, being limited only chip space. Temperature and production spread variations are also considered within the realm of tenability.

Abstract: The present invention provides a dual mode sigma delta analog to digital converter (ADC), which only in one hardware implementation, used for low IF and near zero IF receiver. The dual mode sigma delta ADC comprises a first switched-capacitor integrator; a second switched-capacitor integrator; a quantizer; a feedback circuit and a mode device. By switching the mode device on or off, one could easily change the configuration of the disclosed ADC to decide the receiving signal falling in low-IF or near zero IF.

Abstract: A relaxation oscillator for generating a first and a second oscillation signals, comprising: a reference-voltage providing circuit for providing a high and a low reference voltages; switches for directing the high and low reference voltages to inputs of a transconductance amplifier and a non-inverting input of a comparator; the transconductance amplifier for generating an output current with a value determined by its transconductance value, controlled by an input tuning voltage, and multiplied by its inputs' voltage difference; a capacitor connecting between the transconductance amplifier output and ground; and the comparator for generating a first and a second digital signals; wherein the first and second digital signals are digital control signals to the switches, and the first and second oscillation signal of the relaxation oscillator respectively; wherein the oscillation frequency of the relaxation oscillator is independent of the reference voltages, achieving accurate frequency turning, and simplifying t

Abstract: The device described herein proposes an electronic active filter void of capacitors and inductors. The circuit utilizes only operational amplifiers (Op-Amps) and resistors, hence the name Op-R. Although capable of being constructed of lumped circuit elements this filter is intended for integrated circuit (IC) applications. Filtering of signals can be accommodated sub-audio through the video frequency range depending on the selected op-amp ICs. Low pass, band pass, high pass, as well as ban reject frequency responses are achievable. Although the circuits described herein are single input-single output, multiple inputs and outputs present no difficulty, being limited only by chip space. Temperature and production spread variations are also considered within the realm of tenability.

Abstract: An adjustable equalizer that includes a first branch including a low pass filter (LPF) and having a variable gain (?), and a second branch including a high pass filter (HPF) and having another variable gain (?). The equalizer can be implemented using CMOS technology so that the gain parameters ? and ? are independently adjustable and the equalizer is capable of equalizing an input indicative of data having a maximum data rate of at least 1 Gb/s. In some embodiments, the equalizer includes two differential pairs of MOS transistors and a controllable current source determines the tail current for each differential pair. When the equalizer includes purely resistive impedances Z0 and Z1, the equalizer's transfer function is Z1/Z0·(?+?·(1+s·C0·Z0)), where ? is a gain parameter determined by the tail current of one differential pair and ? is a gain parameter determined by the tail current of the other differential pair.

Abstract: A complex filter for processing an in-phase signal and a quadrature-phase signal includes a first low-pass filter, a second low-pass filter, a connection unit between the first low-pass filter and the second low-pass filter, a first compensation resistor and a second compensation resistor. The first compensation resistor and the second compensation resistor are interlacedly coupled to input resistors of the first low-pass filter and the second low-pass filter.

Abstract: A band pass filter has a high pass filter into which an input signal is input; an amplifier having an inverting input terminal into which an output of the high pass filter is input, wherein the amplifier amplifies an input voltage between the inverting input terminal and a non-inverting input terminal and outputs an output signal to an output terminal; a first resistor connected between a non-inverting output terminal and the inverting input terminal of the amplifier; a first capacitor having a first terminal that is connected to the inverting input terminal; and an inverting amplifier that inverts a polarity of an output signal from the non-inverting output terminal of the amplifier and outputs the inverted signal to a second terminal of the capacitor.

Abstract: An initialization circuit comprises a section signal generator generating a section signal, of which a prescribed section is enabled in response to a power-up signal, a first oscillator generating a first period signal in response to the section signal, a first period multiplier generating a first multiplied signal by multiplying a period of the first period signal, and a signal selector transferring the first multiplied signal or a second multiplied signal selectively as a self-refresh enable signal in response to the section signal.

Abstract: A radio device and a method to operate a non-heterodyne receiver are provided. The radio device is configured to receive a signal waveform and to provide a wake-up signal to a second communication circuit when the signal waveform is a valid communication request; wherein the second communication circuit switches from a power saving state to an operating state upon receiving the wake-up signal from the non-heterodyne receiver. The non-heterodyne receiver further including an Electromagnetic interference (EMI) rejection circuit, including a narrow band filter and a broadband filter to reject an EMI signal. A filter circuit for a narrow passband circuit is also provided. The filter including a buffer circuit; a crystal oscillator coupled to the output of the buffer circuit; and an inverting amplifier coupled in parallel to the crystal oscillator.

Abstract: A circuit and method for filtering a signal. An amplifier (330) receives an input signal (310) and generates a differential output signal. A first resonator (340) having series and parallel resonant frequencies is connected to the positive output port (335) of the amplifier. A second resonator (350) having series and parallel resonant frequencies is connected to the negative output port (336) of the amplifier. The first and second resonators are coupled at a connection point (340). A buffering device (370) receives the combined outputs of the resonators and outputs a filtered signal. The filtering method receives signals and passes them through the elements of the filter circuit to generate a filtered output signal.

Abstract: A filter circuit includes a differential amplifier circuit to provide a number of poles including a dominant pole, and a feedback circuit to feed a portion of an output of the differential amplifier circuit to an input of the differential amplifier circuit. The feedback circuit includes a feedback resistor and a feedback capacitor to provide a controllable increase in an order of a transfer function of the filter circuit along with non-dominant poles of the differential amplifier circuit coupled in parallel with the feedback resistor. Coefficients of a transfer function of the differential amplifier circuit are forced to substantially depend solely on one or more of a plurality of passive circuit elements, the feedback resistor, and the feedback capacitor to control a dependence of the transfer function of the filter circuit on a gain of the differential amplifier circuit and poles of the differential amplifier circuit.

Abstract: Systems and method for detecting potentially harmful harmonic and direct current signals at a transformer are disclosed. One such system includes a plurality of detection components electrically connected to electrical signal lines leading from one or more connection points on a power grid, and a plurality of threshold detectors, each threshold detector configured to compare an incoming signal from a detection component to a predetermined signal having a threshold. The system also includes a controller receiving an output from each of the plurality of threshold detectors and configured to drive at least one external component in response to receiving an indication from at least one of the plurality of threshold detectors of a detected signal above a threshold.

Abstract: Disclosed are a semiconductor integrated circuit device and a wireless communication system that are capable of improving reception sensitivity. The wireless communication system includes, for instance, a first duplexer, a second duplexer, a first low-noise amplifier circuit, and a second low-noise amplifier circuit. A transmission band compliant with a communication standard is split into two segments for use, namely, low- and high-frequency transmission bands. A reception band compliant with the communication standard is split into two segments for use, namely, low- and high-frequency reception bands. The first duplexer uses the low-frequency transmission band and low-frequency reception band as passbands. The second duplexer uses the high-frequency transmission band and high-frequency reception band as passbands.