880results about "Frequency selective two-port networks" patented technology

The invention discloses a symmetrical structure S-band filter based on GaAs IPD, which belongs to the technical field of microwaves and comprises a first-order series resonance circuit, a coupling capacitor C1, a grounding inductor L2, a coupling capacitor C2, a second-order parallel resonance, a third-order parallel resonance, a grounding capacitor C6, a coupling capacitor C7, a fourth-order parallel resonance, a grounding capacitor C66, a fifth-order parallel resonance, a coupling capacitor C22 and a grounding inductor L22. And a coupling capacitor C11 and a sixth-order series resonance. The third-order parallel resonance and the fourth-order parallel resonance can improve the low-frequency out-of-band suppression degree of the band-pass filter; the first-order series resonance and the sixth-order series resonance as well as the second-order parallel resonance and the fifth-order parallel resonance can improve the high-frequency out-of-band suppression degree of the band-pass filter.

The invention discloses a dual-compensation active common-mode EMI filter based on impedance mismatch and a design method thereof, and belongs to the technical field of filter design, the dual-compensation active common-mode EMI filter is connected between an interfered end and an interference source end, the dual-compensation active common-mode EMI filter comprises a voltage sampling circuit, a signal amplification circuit and a compensation circuit, the compensation circuit comprises a voltage injection module and a current injection module, the first end of the voltage injection module is connected with the first end of the voltage sampling circuit, the second end is connected with the second end of the signal amplification circuit, and the third end is connected with the first end of the interference source end; the first end of the current injection module is connected with the second end of the signal amplification circuit, the second end is connected with the third end of the voltage injection module, and the third end is connected with the second end of the interference source end. According to the invention, the insertion loss of the filter can be significantly improved, the filter has an effective bandwidth enough to cover and conduct electromagnetic interference, has better attenuation on full-band noise signals, and has the advantages of small size and high insertion loss.

The utility model relates to a phase interpolator circuit, a clock recovery circuit and a chip, and the phase interpolator circuit mainly comprises a first clock filter which is used for filtering a high-frequency harmonic wave of a first clock signal to generate a first filtering signal; the second clock filter is used for filtering the high-frequency harmonic wave of the second clock signal to generate a second filtering signal; the phase mixer is coupled to the first clock filter and the second clock filter and is used for generating a phase mixed signal according to the first filtering signal and the second filtering signal; and the alternating current coupling output circuit is used for receiving the phase mixed signal and generating an interpolation clock signal according to the phase mixed signal. The phase interpolator circuit can support phase interpolation operation in a wide frequency range, the output linearity performance is optimized, the sensitivity of INL and DNL to power supply amplitude changes is weakened, the duty ratio of the output interpolation clock signal can be optimized, and the interpolation clock signal can support a high-speed interface half-rate transmission mode.

The invention belongs to the technical field of power electronics, and relates to a T-type active EMI filter which comprises a detection link, an amplification link, an injection link and a multiplexing link. The detection link is composed of a detection resistor and a detection capacitor and is used for providing an additional flow path for common-mode current; the amplification link consists of a resistor and an operational amplifier and is used for reversely amplifying voltage at two ends of the detection resistor; the injection link is composed of injection resistors and used for converting voltage signals output by the operational amplifier into compensation current and injecting the compensation current into the multiplexing link, the multiplexing link is composed of a first capacitor and a second capacitor, branches are provided for common-mode current and the compensation current, and meanwhile system differential-mode noise is attenuated; moreover, the T-type three-capacitor structure enables the active suppression circuit to be composed of an operational amplifier and a pure resistor. Therefore, the overall size of the active filter is reduced, design and use are simpler and more convenient, stability is better, and common-mode noise and differential-mode noise can be attenuated powerfully.

The invention discloses an ultra-wideband 6-bit numerical control attenuator with low attenuation amplitude error and low phase change. The digital attenuator is composed of six attenuation units of 0.5 dB, 1 dB, 2 dB, 4 dB, 8 dB and 16 dB. The attenuation units are cascaded according to the attenuation amounts of 0.5 dB, 4dB, 16dB, 8dB, 2dB and 1dB, the attenuation units with the attenuation amounts of 0.5 dB and 1dB adopt a simplified T-shaped structure, the attenuation unit with the attenuation amount of 2dB adopts a bridge T-shaped structure, the attenuation unit with the attenuation amount of 4dB adopts a pi-shaped structure with bypass capacitance compensation, and the attenuation unit with the attenuation amount of 8dB adopts a pi-shaped structure with a bypass compensation capacitor and a branch communication compensation capacitor. And the attenuation unit with the attenuation amount of 16dB is formed by cascading two improved 8dB SPDT switch path type attenuation units. According to the invention, reverse compensation is carried out on phase lag caused by a low-pass filtering network formed by a reference state of a traditional attenuation structure or phase lead caused by a high-pass filtering network formed by an attenuation state, so that the phases of the two are close, and the phase difference between the reference state and the attenuation state is greatly reduced.

An electronic component is provided that includes a substrate, an insulator layer expanding over a surface of the substrate, a planar conductor on the substrate or in the insulator layer and expanding in a plane parallel to the surface of the substrate, and an inductor conductor pattern on the insulator layer or in the insulator layer. When viewed in a direction perpendicular to the surface of the substrate, a length in a longitudinal direction of a region in which a region with the inductor conductor pattern overlapping the planar conductor is represented by Ls, and a distance between the inductor conductor pattern and the planar conductor is represented by d, such that Ls / d is 1 or more and 60 or less.

A filter multiplexer for variable bandwidth annealing selection is described. The filter multiplexer has multiple pathways, where each pathway comprises a switch and a filter. Each filter has a different cutoff frequency from the other filters. Switches may be cryogenic switches. Each pathway may be communicatively coupled to an external annealing line. Upon receiving a problem, an annealing bandwidth can be selected, set or configured via the multiplexer to operate a quantum processor with a desired annealing schedule. The multiplexer may be used for calibration of a quantum processor by performing a calibration with a large annealing bandwidth, then calibrating the quantum processor by iterating through all available annealing bandwidths from the multiplexer.

A device for implementing a non-reciprocal bandpass filter is provided. The device includes a plurality of capacitively-coupled shunt resonators. Each capacitively-coupled shunt resonators includes a plurality of superconducting quantum interference devices (SQUIDs) connected to each other, a flux line inductively coupled to the plurality of SQUIDs, and a capacitor connected in parallel to the plurality of SQUIDs.

The invention relates to an analog active EMI filter with a double-ring structure and a noise suppression verification method. The EMI filter comprises a direct-current power supply, an LISN circuit, a voltage detection circuit, an injection circuit, an amplification circuit and a switching power supply, the direct-current power supply, the LISN circuit, the voltage detection circuit, the injection circuit and the switching power supply are sequentially connected in parallel, the injection circuit comprises a voltage injection branch and a current injection branch connected with the voltage injection branch in parallel, the voltage injection branch and the current injection branch are used for voltage injection and current injection respectively, and the amplification circuit comprises a first anti-phase amplification branch and a second anti-phase amplification branch connected with the first anti-phase amplification branch in parallel. The first anti-phase amplification branch circuit is respectively connected with the voltage detection circuit and the current injection branch circuit to form a first annular structure, and the second anti-phase amplification branch circuit is respectively connected with the voltage detection circuit and the voltage injection branch circuit to form a second annular structure. Compared with the prior art, the method has the advantages of realizing an effective noise interference suppression effect and the like.

Methods, apparatus, systems, and articles of manufacture are described corresponding to current limit circuitry with controlled current variation. An example circuit includes an amplifier having an input terminal and an output terminal; a capacitor having a first terminal and a second terminal, the first terminal of the capacitor coupled to the input terminal of the amplifier, the second terminal of the capacitor coupled to the output terminal of the amplifier; and diode circuitry having a first terminal and a second terminal, the first terminal of the diode circuitry coupled to the first terminal of the capacitor and the input terminal of the amplifier, the second terminal of the diode circuitry coupled to the second terminal of the capacitor and the output terminal of the amplifier.

Methods and apparatus for filtering a signal using a current mode filter circuit that enables source degradation. An example filter circuit generally includes an input node; an output node; a power supply node; a first transistor including a drain coupled with the input node; a second transistor including a drain coupled with the output node and including a gate coupled with a gate of the first transistor; a capacitive element coupled between a drain of the first transistor and the power supply node; a first resistive element coupled between the drain electrode and the gate electrode of the first transistor; a first source degeneration element coupled between a source of the first transistor and the power supply node; and a second source degeneration element coupled between a source of the second transistor and the power supply node.

A method and apparatus for converting an input frequency to a voltage signal using a passive band-pass filter. The method includes providing an input signal having a specified frequency and amplitude to a passive band-pass filter. The method also includes obtaining an attenuated signal corresponding to the input signal from the passive band-pass filter. The method also includes providing the attenuated signal to a peak detector to obtain a direct current (DC) signal having an output voltage proportional to the specified frequency. The passive circuitry includes a first circuit to receive an input signal having a specified frequency and amplitude, and output an attenuated signal corresponding to the input signal. The passive circuitry also includes a second circuit to convert the attenuated signal to a DC signal having an output voltage proportional to the specified frequency.

The invention relates to the technical field of signal processing, in particular to a microseismic sensor front-end signal conditioning circuit based on lag correction frequency expansion. The microseismic sensor front-end signal conditioning circuit based on lag correction frequency broadening comprises a differential amplification circuit used for converting a differential signal input by a microseismic sensor into a single-ended vibration signal and carrying out pre-amplification processing on the vibration signal according to a preset gain to obtain an amplified vibration signal; and the filtering and lag correction circuit is used for widening the frequency range of the amplified vibration signal in a filtering and lag correction mode to obtain a conditioned vibration signal. According to the invention, frequency expansion can be carried out on the magnetoelectric sensor through a low-frequency compensation technology, and the response capability of the magnetoelectric sensor to a low-frequency signal is improved.

The invention relates to the technical field of signal processing, in particular to a large-bandwidth signal source bandwidth flatness compensation method and device based on an FPGA (Field Programmable Gate Array), and the method comprises the steps: playing signal data with required bandwidth through an analog front end based on the FPGA, and measuring an original amplitude-frequency response curve of the signal data through a frequency spectrograph; calculating the amplitude-frequency response of the compensation filter, obtaining a compensation filter coefficient, and quantifying the compensation filter coefficient; sending the quantized compensation filter coefficient to an FPGA to compensate the signal data, playing the signal data through an analog front end, and measuring a first pre-compensation amplitude-frequency response curve in a Nyquist frequency range through a frequency spectrograph; and determining a frequency range exceeding the set bandwidth flatness according to the first pre-compensation amplitude-frequency response curve, and performing independent compensation. Therefore, the influence caused by nonlinearity of a DAC device and related circuits is overcome, the amplitude-frequency response of a large-bandwidth signal source is effectively compensated, the signal flatness in the bandwidth is improved, and the stability and reliability of the system are enhanced.

The invention provides an EMI (Electro-Magnetic Interference) low-pass filter integrated with electrostatic and surge protection functions, which comprises a first TVS (Transient Voltage Suppressor) structure provided with a first P-type well region and a grounded P + heavily-doped active region, a second TVS structure provided with a floating second P-type well region and a grounded P + heavily-doped active region, N + heavily-doped active regions and N + heavily-doped active regions are arranged in the first P-type well region and the second P-type well region, and N + heavily-doped active regions are arranged in the first P-type well region and the second P-type well region. The bottom of the N-type semiconductor substrate is grounded, a forward ESD path in the vertical direction is formed between the N + heavily doped active region in the first P-type well region and the bottom of the N-type semiconductor substrate, and a reverse ESD path in the horizontal direction is formed between the P + heavily doped active region of the first TVS structure and the N + heavily doped active region in the first P-type well region. The second TVS structure is also formed with a forward ESD path and a reverse ESD path. The circuit has the beneficial effects that a high-frequency signal suppression function and electrostatic and surge protection capability can be realized.

The invention discloses a TSV-based tunable inductor structure and a tuning method thereof, the tunable inductor structure comprises a primary side inductor and an auxiliary inductor, the primary side inductor is nested in the auxiliary inductor to form a nested tunable inductor structure; wherein the auxiliary inductor is connected with the modulation source, and the primary inductor is connected with an actual application circuit, so that a voltage difference between a voltage V1 between two ports of the primary inductor and a voltage V2 between two ports of the auxiliary inductor is regulated and controlled through the modulation source, and the primary inductor and the auxiliary inductor are mutually coupled under the action of the voltage V1 and the voltage V2; and the inductance tuning of the primary side inductor is realized. According to the TSV tunable inductor, the TSV tunable inductor structure which is small in tuning range, large in area and high-frequency performance degradation of a traditional tunable inductor is converted into a TSV tunable inductor structure which is based on the magnetic coupling technology, is small in area and wide in tuning range and can be continuously tuned.

The invention relates to the technical field of wireless communication, and provides a power synthesis circuit and a power amplifier. Comprising a first signal input end, a second signal input end, an input impedance matching circuit, a first harmonic suppression circuit, a second harmonic suppression circuit, a first high-pass filter circuit, a second high-pass filter circuit, a low-pass filter circuit and a signal synthesis output end, the low-pass filter circuit comprises a first inductor, a second inductor and a first capacitor; the first end of the first inductor serves as the first input end of the low-pass filter circuit, the first end of the second inductor serves as the second input end of the low-pass filter circuit, the second end of the first inductor is connected with the first end of the first capacitor and the second end of the second inductor and serves as the output end of the low-pass filter circuit, and the second end of the first capacitor is grounded. The power synthesis circuit has the impedance conversion characteristic, and has the advantages of low cost, high isolation, high integration and the like.

The invention discloses a V2X device compensation amplification circuit, a V2X device and an OBU device, the circuit comprises an active amplification circuit and an MCU circuit, the MCU circuit is used for generating a transmit-receive time sequence control signal Switch Control to control the active amplification circuit to transmit or receive a signal; sending a partial attenuation control signal ATTControl to dynamically adjust the attenuation of an adjustable attenuator in the active amplification circuit and maintain the outlet power of the active amplification circuit; the circuit further comprises a transmitting power detection circuit and an antenna detection circuit. According to the invention, on one hand, the power loss can be automatically compensated, so that the communication distance between V2X equipment is increased. And on the other hand, extra cable transmission power supply and control signals do not need to be added, and V2X equipment is convenient to install.

The invention provides an analog correlation circuit of a synthetic aperture radiometer receiver, and relates to the technical field of weak signal detection and processing. The circuit comprises a high-stability power supply reference unit, a high-performance broadband multiplication unit, a low-noise amplification unit and a high-linearity differential active filtering unit, wherein a second-order differential active filter in the high-linearity differential active filtering unit is used for carrying out noise filtering and low-noise amplification on a low-noise amplifier output signal in a differential form, and a differential signal of which the bandwidth is matched with the variation range of the amplitude of a target radiation brightness temperature signal and the amplitude meets the subsequent analog-to-digital conversion requirement is output. The high-linearity differential active filtering unit designed by the invention is realized by a second-order differential active filter formed by connecting two differential active filters in series, a low-pass filter with the cut-off frequency as low as possible filters noise in a link to the maximum extent, only the bandwidth matched with signal change is reserved, the amplitude which is two times of that of a single-ended signal can be provided, and the filtering efficiency is improved. And the linearity and the signal-to-noise ratio performance are better.

To provide a filter stage system.SOLUTION: A filter stage system includes a continuous time baseband filter comprising a feedback loop that employs at least one first impedance node and at least one second impedance node. The at least one first impedance node has a higher impedance than the at least one second impedance node. The at least one first impedance node provides a dominant pole, and the at least one second impedance node provides a non-dominant pole. The continuous time baseband filter generates a filtered current. The filter stage system also includes a mirroring component that mirrors the filtered current to an output.SELECTED DRAWING: Figure 2

The invention provides an adjustable electrical signal impedance matching circuit, and belongs to the technical field of electronics. The circuit can preset the impedance of parallel terminating according to the matching impedance requirement of a transmission signal, monitor the change of signal voltage in the real-time transmission process of the signal, and adjust the current of the impedance conversion module according to the change of the voltage to realize the linear correspondence of the voltage and the current, thereby realizing the matching of the terminating impedance, and improving the transmission reliability of the signal. The impedance matching circuit can flexibly change the size of terminating impedance according to different signal transmission requirements, is particularly suitable for some occasions where various electrical characteristic signals need to be transmitted according to different application requirements, and improves the universality of equipment.

The utility model provides a brushless motor driver Hall filter circuit which comprises a first-stage filter circuit, a second-stage filter circuit and a third-stage filter circuit, the input end of the first-stage filter circuit is connected with a Hall signal, the output end of the first-stage filter circuit is connected with the input end of the second-stage filter circuit, and the output end of the third-stage filter circuit is connected with the output end of the third-stage filter circuit. The output end of the second-stage filter circuit is connected with the input end of the third-stage filter circuit, and the output end of the third-stage filter circuit is connected with the brushless motor driver logic conversion circuit. According to the utility model, the RC forms the first-stage filtering, the NPN triode forms the second-stage filtering, the three-stage filtering circuit formed by the NPN triode performs filtering commutation, the Hall filtering function of the direct-current brushless motor driver is realized through three-stage filtering, the burr interference is filtered, and the problem that the direct-current brushless motor driver cannot be damaged under the high-voltage working condition and the large-current working condition is solved. The problem that Hall signals are interfered to cause commutation errors of the motor is solved, the Hall signal filtering function of the direct-current brushless motor driver is achieved, and the anti-interference capability and reliability of the brushless motor driver are improved.

The invention provides a high-power amplitude limiter with a filtering characteristic. The high-power amplitude limiter comprises a first amplitude limiting module connected with an input port, a second amplitude limiting module connected with an output port and an intermediate cascade module. The first amplitude limiting module comprises a first amplitude limiting circuit and a first reactance module; the first amplitude limiting circuit and the first reactance module are connected in series to a main transmission line of the amplitude limiter. The second amplitude limiting module comprises a second amplitude limiting circuit and a second reactance module; the second amplitude limiting circuit and the second reactance module are connected in series to the main transmission line of the amplitude limiter; the two ends of the middle cascade module are connected in series with inductive reactance elements and then connected to the amplitude limiter main transmission line, and the middle of the middle cascade module is connected in parallel with capacitive elements and then grounded. According to the technical scheme, the original in-band excellent electromagnetic protection characteristic of the amplitude limiter can be ensured while the filtering characteristic is realized, the performance deterioration of a radio frequency receiving signal caused by cascade mismatch of the amplitude limiter and a radio frequency channel post-stage filter is avoided, and the total volume ratio of a radio frequency channel electromagnetic protection device is effectively reduced.

The invention provides a process weak correlation frequency adjustable anti-aliasing filter circuit which is characterized by comprising a current generation module, a current mirror module, a control voltage generation module and an MOSFET-C anti-aliasing filter module. The anti-aliasing filter circuit with the adjustable frequency has the remarkable advantages that the anti-aliasing filter circuit with the adjustable frequency can generate cut-off frequency linearly related to the frequency of an input clock signal, and the anti-aliasing filtering function with the adjustable frequency is achieved. In addition, the circuit can effectively reduce the influence of technological parameters on the cut-off frequency, has good circuit performance, and meanwhile, compared with a cut-off frequency adjusting method of an existing on-chip filter circuit integrated control loop, the circuit is simple in structure, small in introduction power consumption and low in cost. And the anti-aliasing filtering requirement of the ADC acquisition front end within the input clock signal frequency range of 10 kHz to 100 kHz can be met.

A noise reduction circuit includes: noise canceler circuitry configured to inject a compensation current into a power line and ground to reduce a common mode noise current that flows through the power line and the ground into a commercial power supply from a power converter with a switching element connected to the commercial power supply; and overcurrent inhibitor circuitry provided on a compensation current path through which the compensation current flows, the overcurrent inhibitor circuitry being configured to inhibit application of an overcurrent to the noise canceler circuitry.

A noise filter includes: a noise detector which detects voltage due to electromagnetic noise generated by a power converter and outputs adjusted voltage obtained by adjusting the detected voltage; a compensation signal applicator which superimposes compensation voltage having a polarity opposite to the voltage due to electromagnetic noise, on an output or an input of the power converter via a transformer; and an injection voltage generator which generates, on the basis of the adjusted voltage, first output voltage and second output voltage having a polarity opposite thereto, for generating injection voltage between one end and another and of a primary-side winding of the transformer, and outputs the first output voltage and the second output voltage to the one end and the other end, respectively.

One or more systems, devices and / or methods of use provided herein relate to a baseband filter that can be used in a current-mode end-to-end signal path. The current-mode end-to-end signal path can include a digital to analog converter (DAC) operating in current-mode and an upconverting mixer, operating in current-mode and operatively coupled to the DAC. In one or more embodiments, a device used in the signal path can comprise a baseband filter that receives an input current and outputs an output current. The baseband filter can comprise a feedback loop component having an active circuit branch and a passive circuit branch coupled in a loop. A mirroring device can be coupled to the feedback loop component and can provide an output of the device. Selectively activating the mirroring device can vary gain, such as of the mirroring device.

A filter stage system comprising a continuous-time baseband filter comprising a feedback loop employing at least one first impedance node and at least one second impedance node, wherein the at least one first impedance node has a higher impedance than the at least one second impedance node, and wherein the at least one first impedance node provides a dominant pole and the at least one second impedance node provides a non-dominant pole, and wherein the continuous-time baseband filter generates a filtered current, and a mirror component mirrors the filtered current to an output.

A bidirectional adaptive current sampling circuit comprises a sampling unit, a sampling switching module, a first differential current sampling circuit, a second differential current sampling circuit and a control module. The sampling unit is connected in the main circuit to obtain sampling current; the control module controls the sampling switching module to perform switching in a communication manner, so that the sampling unit is accessed to the first differential current sampling circuit and the second differential current sampling circuit in a forward direction or a reverse direction; the first differential current sampling circuit and the second differential current sampling circuit acquire different amplification signals based on the sampling current; the control module generates a current sampling signal based on the different amplified signals and a set threshold. According to the bidirectional self-adaptive current sampling circuit, the sampling switching module is arranged, bidirectional current sampling can be achieved, so that the sampling range is widened, the sampling precision can be met through different differential current sampling circuits, and the sampling result is more accurate.