30results about "Negative-feedback-circuit arrangements" patented technology

A system and method are used to maintain a variance in feedback factors of an amplifier between the first and second phases either below a threshold value or within a specified range. The system includes the amplifier and first through third capacitances. The amplifier is coupled between an input node and an output node that operates during first and second phases of operation. The first capacitance is coupled across the amplifier and between the input node and the output node during the first and second phases of operation. The second capacitance is coupled to the input node during the first phase of operation. The third capacitance is coupled to one of the input and output nodes during one or both of the first and second phases of operation.

This application provides an operational amplifier, a chip, and an electronic device, and relates to the field of integrated circuit technologies. The operational amplifier includes a first power voltage end, a second power voltage end, a first-stage operational amplification circuit, and a second-stage operational amplification circuit. The first power voltage end is configured to receive a first power voltage signal, the second power voltage end is configured to receive a second power voltage signal, and a voltage value of the first power voltage signal is greater than a voltage value of the second power voltage signal. The first-stage operational amplification circuit is configured to: receive an input signal via a signal input end, and amplify the input signal under enabling control of the first power voltage signal, to generate a first drive signal. The second-stage operational amplification circuit is configured to: generate an output signal based on the first drive signal under enabling control of the second power voltage signal, and output the output signal via a signal output end. The operational amplifier has performance like low noise, low power consumption, high rate, and small area, and can be used in a chip.

The application relates to an output version configurable circuit based on a DC-DC converter, and belongs to the field of DC-DC converter circuit design; the circuit comprises a voltage scaling circuit, a decoder logic circuit, a trimming circuit, an error amplifier and a feedback network; wherein the decoder logic circuit comprises a first-stage logic circuit, a second-stage logic circuit, a first NMOS tube matrix and a second NMOS tube matrix; in an initial state, each NMOS tube in the first NMOS tube matrix and the second NMOS tube matrix is in an off state; the circuit can adjust the feedback network voltage dividing resistor proportion through a trimming signal according to actual requirements, thereby changing the proportion of a feedback voltage Vsense and an output voltage VOUT, so that the adjustment of different output versions is realized; meanwhile, the voltage selection signal of the decoding logic is adjusted through the trimming signal, thereby changing a reference signal Vref, and the different output versions and the output voltage precision configurable are realized.

This application relates to methods and apparatus for clipping prevention. A driver apparatus for driving a load with an output signal has a switching driver with a switch network and a modulator configured to control the switch network to switch output nodes between different switching voltages with a controlled duty-cycle. A quantizer controller receives a quantizer input signal based on an input signal and a feedback signal and controls the duty-cycle of the switch network. A clipping prevention controller is configured to control a gain applied to the input signal so as to provide limiting of the input signal to avoid clipping, wherein the clipping prevention controller is configured to dynamically control at least one limiting threshold used to determine when to apply limiting of the input signal based on an indication of said quantizer input signal.

The application discloses a kind of radio frequency amplification circuit and single-photon radiation detector time response test system, belong to radio frequency signal processing technical field.The radio frequency amplification circuit includes: input module;Double gate control module, including first gate control unit and second gate control unit;Amplifier and feedback module, its input end connects input module, output end connects second gate control unit, control end connects first gate control unit;Output module.First gate control unit detects input signal envelope, when exceeding preset threshold, generates gate control strobe pulse, controls amplifier and feedback module to enter working state, otherwise enter cut-off state;Second gate control unit is when amplifier and feedback module enter cut-off state, quickly discharge output end residual charge to inhibit signal tailing.The application blocks wideband noise false trigger from source by adaptive gate control mechanism, and eliminates baseline disturbance by active clamping discharge, compresses signal tailing recovery time to within 2 nanoseconds, significantly improves the measurement accuracy of single-photon detector time response parameter, and has the advantages of high gain, low noise, wide bandwidth, fast transient response.

The present application relates to the technical field of electronic measurement, more particularly, it is especially related to a composite pressure expansion, flow expansion and frequency expansion circuit, which comprises an input signal source, a front-stage precision operational amplifier circuit, a rear-stage high-voltage and high-current operational amplifier circuit and a feedback loop, the input signal source is connected with the input end of the front-stage precision operational amplifier circuit, the output end of the front-stage precision operational amplifier circuit is connected with the input end of the rear-stage high-voltage and high-current operational amplifier circuit, and the feedback loop is connected between the output end of the rear-stage high-voltage and high-current operational amplifier circuit and the input end of the front-stage precision operational amplifier circuit.The present application uses cascaded operational amplifier circuits to realize a high-precision, high-voltage, high-current and wide-frequency output circuit.Through multi-stage operational amplifier cascading and feedback configuration, higher closed-loop gain is obtained under the premise of ensuring stability, and the effective bandwidth is expanded to meet the high-frequency or high-gain signal processing requirements.

The application belongs to the technical field of audio power amplifier filtering, and particularly relates to a band-pass filter circuit for eliminating radio frequency interference of an audio power amplifier. The band-pass filter circuit comprises an operational amplifier AMP, a reference voltage BYP connected to a non-inverting input terminal of the operational amplifier AMP, an input impedance network connected between an audio input terminal IN grounded and an inverting input terminal of the operational amplifier AMP, and a feedback impedance network connected between an output terminal and the inverting input terminal of the operational amplifier AMP. The feedback impedance network is composed of two parallel feedback branches. A first feedback branch is composed of a resistor R2, and a second feedback branch is composed of a resistor R3 and a capacitor C2 connected in series. A zero point is introduced in a transfer function of the band-pass filter circuit, and a zero point frequency is determined by a resistance value of the resistor R3 and a capacitance value of the capacitor C2, so as to suppress a gain near the zero point frequency, thereby effectively suppressing interference of high-frequency noise.

The application discloses a programmable gain amplifier and a control method thereof. The programmable gain amplifier comprises a first differential amplifier circuit, a first set of gain resistors, a second set of gain resistors, a set of sampling capacitors, a first set of switches and a second differential amplifier circuit. The first set of switches is used for selectively coupling the first set of gain resistors between an inverting input voltage and an input of the first differential amplifier circuit, coupling the second set of gain resistors between a common-mode voltage source and the input of the first differential amplifier circuit, and coupling the set of sampling capacitors with respective outputs of the first differential amplifier circuit during a first stage of an offset calibration of the first differential amplifier circuit. Through storage of the sampling capacitors and negative feedback of the second differential amplifier circuit, an offset voltage on the first differential amplifier circuit is offset, so that the influence of the offset voltage on a front-stage amplifier circuit on detection accuracy can be effectively reduced.

A transmitter having a transmitter signal processor (TSP) is provided for processing a plurality of signals for transmission to produce an output signal of constant envelope. The TSP has a sum input c

This application relates to a one-dimensional non-Hermitian configuration circuit for realizing the non-Hermitian skin effect, belonging to the field of topology circuits. The circuit includes a first node, a second node, and a third node; the first node and the second node are connected via intra-cell capacitance, and the first node and the third node are connected in parallel via intra-cell capacitance and a first voltage follower branch; the second node and the third node are connected in parallel via intra-cell capacitance and a second voltage follower branch; one end of the third node is connected to an inter-cell capacitance; one end of the first node is connected to a first ground branch, and the other end of the first ground branch is grounded; one end of the second node is connected to a second ground branch, and the other end of the second ground branch is grounded; one end of the third node is connected to a third ground branch, and the other end of the third ground branch is grounded. This application solves the problem that the SSH model framework cannot achieve independent or coordinated control due to the inability to introduce multiple non-reciprocal couplings.

The application relates to the technical field of linear feedback of amplifiers, and particularly relates to a negative feedback power amplifier circuit, a power amplifier circuit control method and a negative feedback power amplifier system. The circuit comprises a power input module, a power amplifier module, an output port and a feedback module, the power amplifier module is connected with the power input module and the output port, the input end of the feedback module is connected with the output port, and the output end of the feedback module is connected with the control end of the power input module and the control end of the power amplifier module. The circuit can detect whether the power amplifier module works in a linear working area, and when the linear working area is exceeded, the feedback module is used to control the power amplifier module to reduce output power, or the power input module is used to control input power to be reduced, so that the power amplifier module is backed to the linear working area. Multiple mixers and other radio frequency active devices do not need to be arranged, the cost is controlled, the adjustment range of input power is improved through the power input module, and the applicability is higher.

This application provides a current-type Hall effect sensor circuit, belonging to the technical field of Hall effect sensor circuits. Addressing the problem of poor output signal stability in Hall effect sensor circuits, this application provides a current-type Hall effect sensor circuit, including: an operational amplifier, a voltage divider unit, a feedback unit, a first RC low-pass filter unit, and a second RC low-pass filter unit; the first RC low-pass filter unit is connected between the non-inverting input terminal of the operational amplifier and an external driving module, which outputs a Hall signal during driving; a voltage divider unit is connected between the inverting input terminal of the operational amplifier and the power supply voltage terminal, and a feedback unit is connected between the output terminal of the operational amplifier and its inverting input terminal, forming a feedback loop, with the power supply voltage terminal providing the power supply voltage signal; the second RC low-pass filter unit is connected between the output terminal of the operational amplifier and an external processing module. This application has strong adaptability and high output signal stability.

This invention provides a passive infrared detection device that can shorten power-on time. The passive infrared detection device includes a pyroelectric infrared sensor and an amplifier circuit. The amplifier circuit uses a non-inverting negative feedback amplifier circuit powered by dual power supplies as the primary amplifier circuit. A step-down voltage divider circuit is configured to pull down the DC bias voltage of the detection signal output from the signal output terminal of the pyroelectric infrared sensor. In this way, at the beginning of power-on of the passive infrared detection device, there is a small voltage difference between the non-inverting and inverting input terminals of the operational amplifier of the primary amplifier circuit. This reduces the time required for the voltage between the non-inverting and inverting input terminals of the operational amplifier to become consistent during the charging and discharging process, thereby shortening the power-on time of the primary amplifier circuit.

A sensor component is disclosed comprising a transducer and an electrical circuit arranged in a single package. The electrical circuit includes a bias voltage coupled to a first electrode of the transducer. A non-inverting amplifier stage is coupled to a second electrode of the transducer. An inverting amplifier stage is coupled to an output of the non-inverting amplifier stage. A negative feedback path is located between an output of the inverting amplifier stage and the first electrode of the transducer. An electrical output signal of the transducer can be attenuated by applying an attenuation signal, based on a filtered electrical signal, to the first electrode via the negative feedback path.

This invention discloses a rail-to-rail operational amplifier with transient enhancement and low noise characteristics. The invention includes: a rail-to-rail constant transconductance input stage, a high-gain cascode intermediate stage, a high-drive-capability Class AB output stage, an op-amp self-biasing circuit, and a transient enhancement circuit. The output of the rail-to-rail constant transconductance input stage is connected to the input of the high-gain cascode intermediate stage. The output of the high-gain cascode intermediate stage is connected to the input of the high-drive-capability Class AB output stage. The self-biasing circuit design removes the size constraint of the current mirror tube, allowing for the use of a larger current mirror tube. Simultaneously, the input pair adopts a subthreshold biased rail-to-rail constant transconductance input structure, effectively suppressing various noise interferences in the circuit and providing a clean amplification environment for weak signal processing, ensuring that the signal maintains good accuracy and integrity during amplification.

A system includes a radio frequency (RF) receiver having a low noise trans-impedance amplifier (LNTA) (101). The LNTA is configured to receive a single-ended RF voltage signal and convert the RF voltage signal to a differential current mode signal. Further components in an RF signal chain are configured to receive the differential current mode signal. The LNTA includes cascode amplifiers (N1l, N2, N3, N4, P1, P2, P3, P4).

This utility model relates to an ultrasonic smart gas meter vibration detection circuit. Its features include a vibration detection circuit employing an electromagnetically inductive omnidirectional vibration sensor to convert vibration amplitude into an electrical signal; an operational amplifier processing circuit including a filter circuit, a decoupling circuit, and an operational amplifier to amplify and filter the weak signal output by the omnidirectional vibration sensor; an output signal control circuit that raises the bias voltage of the operational amplifier through a resistor voltage divider to ensure that the weak signal can activate the transistor in the output signal determination circuit; and an output signal determination circuit that converts the analog signal into a digital level signal using the switching characteristics of the transistor to determine whether vibration has occurred. This utility model, using an electromagnetically inductive vibration sensor and signal processing circuit, combined with filtering, decoupling, and operational amplifiers, can accurately capture weak vibration signals from the gas meter and its surrounding environment, ensuring the detection of minute vibration changes, exhibiting high sensitivity, and enabling timely response to vibration signals.

A low noise amplifier and an ultra-wideband receiver are provided. In the low noise amplifier a first amplifying unit includes a first common-source amplifier transistor, a second common-source amplifier transistor, a first negative feedback unit, a second negative feedback unit and an inter-stage matching unit. In the inter-stage matching unit the sixth inductor is in connection with a drain of the first common-source amplifier transistor, and the sixth inductor is in connection with the fourth capacitor to form a feedback node, the first transmission line inductor is in suspended connection with the feedback node, and the fourth capacitor is in connection with the gate of the second common-source amplifier transistor, the first negative feedback unit is in cross-connection between the first common-source amplifier transistor and the feedback node, and the second negative feedback unit is in cross-connection between the second common-source amplifier transistor and the feedback node.

Methods and apparatuses for amplifying a signal via an amplifier circuit for transmission are described. An example amplifier circuit generally includes an amplifier configured to amplify a signal for wireless transmission and including a first transistor (Q 2p ) and a second transistor (Q 2n ). The amplifier circuit also includes a transformer coupled to an output of the amplifier, a first coil (L1) coupled to the first transistor (Q 2p ) and inductively coupled to the transformer, and a second coil (L2) coupled to the second transistor (Q 2n ) and inductively coupled to the transformer.

This invention discloses a sensor output conversion circuit, comprising: a conditioning chip, a voltage regulator, a path controller, and a negative feedback amplifier circuit. The negative feedback amplifier circuit includes an operational amplifier electrically connected to a first resistor, a second resistor, and a third resistor, used to convert a conditioned output signal in a first voltage range into a conditioned signal output in a second voltage range. This invention utilizes the virtual ground, near-infinite input impedance, and near-infinite common-mode rejection ratio of the operational amplifier to convert a conditioned output signal in the 0-5V range into a conditioned signal output in the 0-10V range, achieving a linear electrical connection between the sensor circuit and the industrial equipment circuit. Furthermore, by selecting components with different parameters and switching paths using the path controller, the initial signal calibration and conditioned signal output of the front-end conditioning chip can be conveniently achieved.

This invention discloses a high-stability BOOST circuit with wide load range and its control method, comprising a power stage circuit and a mode switching circuit. The mode switching circuit generates control signals ctl1 and ctl2 based on the output signal VOUT and provides them to the power stage circuit. This invention does not sacrifice dynamic performance during ultra-wide load switching. Instead, it adjusts Rcomp by monitoring the load current, enabling the loop bandwidth to vary with the zero point of the right half-plane. This solves the trade-off between transient response and stability under ultra-wide load conditions, improving system performance.

An amplifier circuit is provided. The amplifier circuit includes a first transimpedance amplifier and a first transconductance amplifier. The first transimpedance amplifier is to receive a first input signal. A first input of the first transconductance amplifier is coupled to a first output of the first transimpedance amplifier. The first transconductance amplifier includes a first passive feedback structure and a first active feedback structure. The first passive feedback structure includes a first resistor coupled between the first output of the first transimpedance amplifier and the first input of the first transimpedance amplifier. The first active feedback structure includes a first inverter having an output coupled to the first input of the first transimpedance amplifier. This configuration optimizes the gain-bandwidth product and stability of the amplifier circuit.

A low noise amplifier operating in an X-band and a Ku-band, the amplifier includes: a differential input unit that adjusts an impedance of an input low noise signal; a differential amplification unit comprising a positive wideband filter that feeds back an 8 to 16 GHz band signal from a positive low noise signal transmitted by the differential input unit, a negative wideband filter that feeds back an 8 to 16 GHz band signal from a negative low noise signal transmitted by the differential input unit, a positive amplification unit, and a negative amplification unit that amplifies a negative low noise signal transmitted by the differential input unit; and a differential output unit that outputs a positive low noise signal amplified by the positive amplification unit and a negative low noise signal amplified by the negative amplification unit.

A radio frequency integrated circuit (RFIC) comprising: a power amplifier (PA) connected to an antenna (348) by a first electromagnetic (EM) element, the PA configured to receive a transmit signal from a second EM element; a low noise amplifier (LNA) connected to the first EM element and the second EM element, the power amplifier and the LNA comprising separate amplifier cores, and wherein the first EM element comprises a first plurality of interwound windings occupying a first common area, and the second EM element comprises a second plurality of interwound windings occupying a second common area.

Disclosed is a radio frequency power amplifier that reduces load change sensitivity, which comprises a feedback circuit (10) and a plurality of levels of amplification circuit, the feedback circuit (10) and all or a portion of amplification circuit among the plurality of levels of amplification circuit being connected in parallel between a first node (M) and a second node (N), and a feedback loop made up of the feedback circuit (10) and an amplification circuit main path located between the first node (M) and the second node (N) forming a 180°+360°×n phase shift, where n is a natural number.

This circuit provides a way to lower the output impedance before negative feedback in an acoustic signal amplifier for accurately driving dynamic speakers. [Solution] The circuit uses a common collector configuration for the amplifier's output stage, inserting a resistor between its input and ground, either DC or AC. By setting the resistance value of this resistor to a value sufficiently smaller than the product of the speaker impedance and the output stage's current amplification factor, it becomes possible to voltage-drive the speaker without negative feedback.

This utility model discloses a preamplifier circuit and an insect detection device. The preamplifier circuit, used for insect detection, includes: an input module whose input terminal is connected to the input terminal of the preamplifier circuit; an output terminal of the input module connected to the input terminal of a non-inverting input bias module; and the non-inverting input bias module connected to the non-inverting input terminal of an operational amplifier. A first terminal of an inverting input feedback module is connected to the output terminal of the operational amplifier; a second terminal of the inverting input feedback module is connected to the first terminal of the output module; a third terminal of the inverting input feedback module is connected to the inverting input terminal of the operational amplifier; and a second terminal of the output module is connected to the output terminal of the preamplifier circuit. This preamplifier circuit for insect detection solves the problem of poor signal amplification and feedback stability during insect detection, thus improving the accuracy of insect detection.

The utility model provides a passive infrared detection device that can shorten the power-on time, which comprises a pyroelectric infrared sensor and a multi-stage amplification circuit. The multi-stage amplification circuit comprises a primary amplification circuit and at least two secondary amplification circuits. Each stage of amplification circuit is provided with a negative feedback amplification circuit and has an operational amplifier OP, a feedback resistor R1 connected between the inverting input and output of the operational amplifier OP, and a series RC circuit connected to the inverting input of the operational amplifier OP. The total amplification factor of the multi-stage amplification circuit is greater than or equal to 1000, and the ratio of the resistance R1 in the feedback resistor and the resistance R in the series RC circuit in the same stage of amplification circuit satisfies 1 < R1:R ≤ 40. In this way, without changing the high-pass cutoff frequency and total amplification factor of the multi-stage amplification circuit, the power-on time is shortened by increasing the number of stages of the multi-stage amplification circuit and reducing the amplification factor of each stage of amplification circuit.

The embodiment of the application provides a novel differential amplifier with a feedforward bias correction circuit and equipment, a common-mode voltage output of the differential amplifier is dynamically adjusted by the bias correction circuit according to an input voltage, and then input voltage errors of the differential amplifier caused by common-mode voltage output offset can be greatly reduced, so that a very small input signal can be detected with high precision, a common-mode adjustment channel is assisted to track the common-mode voltage output, so that the common-mode voltage output offset is reduced, and the precision of the differential amplifier is improved.