561results about "Amplifier modifications to extend bandwidth" patented technology

The invention provides a broadband low-noise amplifier based on a three-coil coupling transformer. The broadband low-noise amplifier comprises an input matching network, a common-source differential output driving stage amplifier, an inter-stage matching network, a common-source differential output power stage amplifier and an output matching network which are connected in sequence, broadband matching is realized by using the input matching network and the inter-stage matching network, and the effective transconductance of the transistor is improved; through the cross-coupled capacitors, the LNA gain and stability on a broadband are improved, better isolation is realized, and input and output are decoupled; due to the design of the grounding capacitor, the linearity of the LNA is improved; through the combination of the three-coil coupling transformer and the differential topology, output signals are superposed in the same direction at the output end, and noise is cancelled in the reverse direction at the output end, so that the thermal noise is greatly inhibited, the isolation is improved through the output matching network, the insertion loss is reduced, and the output matching performance is optimized.

The utility model relates to a radio frequency power amplification circuit with a harmonic suppression function and a radio frequency chip. The radio frequency power amplification circuit comprises an input matching unit, a first-stage power amplification unit, a first-stage bias unit, a first-stage power supply unit, an inter-stage matching unit, a second-stage power amplification unit, a second-stage bias unit, a second-stage power supply unit and an output matching unit. According to the utility model, the LC type trap circuits are designed and used in the power supply unit and the inter-stage matching unit, so that secondary, tertiary and high-order harmonic suppression is realized in the radio frequency power amplification circuit; meanwhile, based on LC circuit structures in the power supply unit and the inter-stage matching unit, the inter-stage matching bandwidth is widened, and the linearity of the multi-stage power amplification unit is improved.

The invention relates to the technical field of radio-frequency signal processing, and discloses a 5G radio-frequency signal amplification method and system, and the method comprises the steps: decomposing an obtained radio-frequency signal into a high-frequency sub-band and a low-frequency sub-band through a multilayer wavelet packet, judging whether the radio-frequency signal is sparse in a wavelet packet domain, and carrying out the sparse reconstruction of an LI norm minimization problem if the radio-frequency signal is sparse; obtaining feature data of each sub-band, extracting a nonlinear transfer function of each sub-band through a CNN-GRU network, and carrying out transfer learning pre-training and dynamic adaptation updating; on the basis of dynamic adaptation update ending, layered memory polynomial calculation and layered model joint output construction, layered model parameter optimization is converted into a least square problem to obtain an error compensation function, and resource allocation is dynamically adjusted according to the peak-to-average power ratio of an input signal; and based on power amplifier state data, holographic sensing is performed on nonlinear parameters of the device through a fusion model, and dynamic changes of the device are compensated through multi-stage calibration and calibration delay is controlled.

The invention discloses a power synthesis amplifier which comprises two power amplification structures, and each power amplification structure is composed of an input matching circuit, a driving stage amplifier DA, an inter-stage matching circuit, a power stage amplifier PA and an output matching circuit. The input end of the power synthesis amplifier is connected by a T-junction power distribution network; the output end of the power synthesis amplifier is connected with the T-junction power synthesis network. The output power of the power amplifier is improved by adopting a two-path synthesis technology, specifically, the power amplifier can be expanded to multiple paths according to needs, and an output power synthesis network adopts a current type synthesis network, so that the amplitude-phase balance of two paths of output signals and the current processing capability of a circuit are ensured, and the output efficiency is improved; the output-stage matching circuit adopts a transformer with a high coupling coefficient to reduce signal loss, the input and inter-stage matching networks adopt a transformer with a low coupling coefficient to play a role in expanding bandwidth, and the multi-stage matching circuit can be widely applied to the technical field of mobile communication and radar detection.

The invention discloses an ultra-wideband high-linearity power amplifier with a negative feedback structure. The ultra-wideband high-linearity power amplifier comprises an input matching network, a driving-stage amplifying circuit, an inter-stage matching network, a power-stage amplifying circuit, an output matching network, a negative feedback RLC (Radio Link Control) network and a self-adaptive biasing circuit, an input radio-frequency signal is transmitted to the driving-stage amplification circuit through the input matching network for primary amplification, transmitted to the power-stage amplification circuit through the inter-stage matching network for secondary amplification and output through the output matching network, and the driving-stage amplification circuit comprises a first transistor and a second transistor. The power level amplification circuit comprises a third transistor and a fourth transistor; the self-adaptive bias circuit is used for providing self-adaptive bias voltage for the first transistor and the third transistor; the negative feedback RLC network is used for controlling the gain and bandwidth of the amplifier and comprises a driving-stage negative feedback network and a power-stage negative feedback network. The working bandwidth of the power amplifier can be widened, and the gain, the output power and the linearity of the amplifier can be improved.

The invention discloses a self-stabilization zero operational amplifier circuit free from input imbalance and common mode influence, relates to the technical field of integrated circuits, and is applied to a high-precision operational amplifier. The operational amplifier is a three-stage operational amplifier and mainly comprises a single auxiliary input end zeroing amplifier, a main amplifier and an output stage. After a zero setting auxiliary input end of a traditional zero setting amplifier is changed into single-end input from differential input and a zero setting input stage is subjected to multi-stage design, an offset voltage of 3.8 microvolts, a low-frequency gain of 189dB and a gain bandwidth product of 8.6 MHz are realized under power consumption of 400 microamperes, the phase margin of the operational amplifier is 78 degrees under unit gain, and the stability requirement is met. Compared with a traditional structure, the low-residual-offset operational amplifier has the advantages that lower residual offset and larger operational amplifier bandwidth are achieved, and the application range is wider.

The invention discloses a broadband power amplifier with an output reconfigurable network, and relates to the technical field of microelectronics, the broadband power amplifier with the output reconfigurable network adopts a three-stage amplification circuit with a gate width ratio of 1: 2: 8, and signal pre-amplification and gain improvement are realized through the first two stages of amplifiers; the last-stage eight-tracheid parallel structure outputs saturated power under high-voltage power supply and realizes power additional efficiency; the output reconfigurable network is controlled by a first switch and a second switch, the first switch is turned off and the second switch is turned on in a high-power mode, so that a compensation microstrip line is grounded to form a fundamental wave matching branch knot, the loss of a harmonic suppression network is avoided, and high-efficiency output is guaranteed; in a low-power mode, the first switch is switched on, the second switch is switched off, the first LC resonance unit and the second LC resonance unit jointly form a band-stop filtering network, secondary and third harmonic impedance is adjusted to be in a near-short-circuit state, so that generation of higher harmonics is restrained, phase distortion is offset through the compensation microstrip line, and the integrity of fundamental wave signals is maintained.

The invention discloses a multi-mode ultra-wideband continuously adjustable microwave power amplifier circuit, and belongs to the technical field of microwave integrated circuits. Switching between the ultra wide band and multiple communication frequency bands can be realized by adjusting the control voltage and the drain electrode power supply circuit of the pre-stage circuit, and the center frequency of the communication frequency bands can be independently designed. And the center frequency of the communication frequency band can be changed by changing the values of the capacitor and the inductor in the continuous adjustable branch knot and the inductor in the drain power supply circuit of the pre-stage circuit. Through on-chip voltage and external voltage switching control, mode switching of the ultra wide band and multiple communication frequency bands can be realized, and the problems that the ultra wide band and the communication frequency bands of the high-performance power amplifier can be switched and the communication frequency is continuously adjustable are solved.

The embodiment of the invention provides a radio frequency power amplifier and a radio frequency front-end module. The radio frequency power amplifier comprises a first radio frequency amplification circuit, a second radio frequency amplification circuit, a first transformer, a second transformer and a coupler, the first radio frequency amplification circuit is used for outputting a first radio frequency signal, and the second radio frequency amplification circuit is used for outputting a second radio frequency signal; the first transformer comprises a first coil and a second coil, and the second transformer comprises a third coil and a fourth coil; the first coil is connected with the first radio frequency amplification circuit, and the second coil is coupled with the first coil to output a first coupling signal corresponding to the first radio frequency signal; the third coil is connected with the second radio frequency amplification circuit, and the fourth coil is coupled with the third coil to output a second coupling signal corresponding to the second radio frequency signal; the coupler is used for performing power synthesis on the first coupling signal and the second coupling signal to output a synthesized signal. The radio frequency power amplifier and the radio frequency front-end module have better bandwidth performance.

Apparatus and methods for power amplifiers with broadband matching networks are disclosed. In certain embodiments, a mobile device includes a transceiver that generates a radio frequency input signal, and a front-end system including a compound semiconductor die and a silicon switch die. The compound semiconductor die includes a power amplifier including one or more power amplifier stages that amplify the radio frequency input signal to generate a radio frequency output signal. The silicon switch die includes a band selection switch that receives the radio frequency output signal. The compound semiconductor die and the silicon switch die each include at least one controllable impedance for providing a bandwidth adjustment to the power amplifier.

The invention discloses a high-linearity medium-power amplifier based on cascode RC negative feedback and a composite matching network. The high-linearity medium-power amplifier comprises a common-source transistor M1, a common-gate transistor M2, a single power supply VDD with an active bias circuit, an input matching network, an output matching network and a negative feedback loop, the input matching network comprises an inductor Lb and an inductor Lg, the output skin matching network comprises an inductor Ld1 and an inductor Ld2, and the negative feedback loop comprises a resistor Rf and a capacitor Cf; the source electrode of the common source transistor M1 is connected with the drain electrode of the common gate transistor M2, one side of the active bias circuit is connected to the grid electrode of the common source transistor M1 through the inductor Lb and the inductor Lg in sequence, the common end of the inductor Lb and the inductor Lg is connected with the input end, and the resistor Rf and the capacitor Cf are connected in series and connected between the grid electrode of the common source transistor M1 and the output end. One side of the inductor Ld2 is connected with the source electrode of the common-gate transistor M2, the other side of the inductor Ld2 is connected with one side of the inductor Ld1, the other side of the inductor Ld1 is connected with the single power supply VDD, and the common end of the inductor Ld1 and the inductor Ld2 is connected with the capacitor Cf and the output end; the method is suitable for radar and communication systems in industrial application, and has important significance for developing high-performance, low-cost and high-integration-level multifunctional chips.

The invention belongs to the technical field of integrated circuits, and particularly relates to a radio frequency amplifier bandwidth expansion circuit based on resistor-capacitor series feedback. The bandwidth expansion circuit comprises a first-stage common-gate amplifier, a second-stage common-source amplifier, a transformer-based inter-stage matching network between the two stages of amplifiers, and two resistor-capacitor series feedback paths, and a resistor-capacitor series feedback path is bridged at two sides of the interstage matching network, and feedback is introduced from the output end of the common source amplifier to the output end of the common gate amplifier, so that the quality factors of two resonant cavities of the interstage matching transformer are adjusted, and the targets of adjusting the gain of the amplifier and expanding the bandwidth of the radio frequency amplifier are further realized.

Apparatuses and systems implementing an amplifier module are described. The amplifier module can include a substrate. A driver amplifier die, a splitter network, an output amplifier die, a bias controller, and a combiner network can be coupled to the substrate. The driver amplifier die can be configured to receive an input radio frequency (RF) signal. The splitter network can be configured to split an intermediate RF signal outputted from the driver amplifier die into first and second RF signals. The output amplifier die can be configured to receive the first and second RF signals. The bias controller can be configured to bias the driver amplifier die and the output amplifier die. The combiner network can be configured to combine first and second outputs of the output amplifier die to generate an output RF signal and terminate at least one harmonic of the output amplifier die's output impedance.

A hybrid coupler has a first port, a second port, a third port, and a fourth port to which a load is connected. An input signal distributor distributes a first input signal that is a radio frequency signal into a second input signal and a third input signal. The second input signal is inputted to a balanced amplifier. The balanced amplifier outputs two amplified radio frequency signals with a phase difference of 90° from each other from two output ends, one of which is coupled to the first port and another one of which is coupled to the second port. The control amplifier amplifies the third input signal and outputs the amplified third input signal from an output end. The output end of the control amplifier is coupled to the third port without any circuit component affecting impedance matching disposed in between.

A radio frequency (RF) power amplifier based on transformer matching is provided. The RF power amplifier includes: a first-stage amplification circuit configured with an input terminal and an output terminal, wherein the output terminal of the first-stage amplification circuit is configured to be connected to one terminal of a main coil of a first transformer; the first transformer configured to include the main coil and a secondary coil, wherein one terminal of the secondary coil is grounded and the other terminal of the secondary coil is connected to a medium-low power mode input terminal of a power switch; the second-stage amplification circuit configured with an input terminal for receiving the amplified RF signal from the first-stage amplification circuit, wherein an output terminal of the second-stage amplification circuit is configured to be connected to a high power mode input terminal of the power switch.

The invention discloses a bandwidth expansion circuit, a chip and a receiver, and belongs to the technical field of analog integrated circuits. The bandwidth expansion circuit comprises a signal compensation equalization module, a first bandwidth boosting module and a second bandwidth boosting module, the signal compensation equalization module is used for carrying out equalization amplification on a high-frequency component in the received first signal and outputting an equalized and amplified second signal; the second bandwidth boosting module is used for feeding back the extracted low-frequency component to the output end of the signal compensation equalization module so as to lower the low-frequency component in the second signal; the first bandwidth boosting module is used for offsetting high-frequency attenuation of the capacitive load on the second signal after the low-frequency component is reduced, and sending a third signal after offsetting the high-frequency attenuation through the signal output end; and the second bandwidth boosting module is also used for extracting a low-frequency component from the third signal. Through the combination of various technologies of compensating channel attenuation, counteracting capacitance influence, lowering low-frequency components and the like, the effective improvement of the circuit bandwidth is realized.

The invention discloses a single-power-supply ultra-wideband temperature compensation low-noise amplifier circuit, and belongs to the technical field of radio frequency microwaves. The circuit is mainly composed of a pre-stage low-noise amplifier module, an inter-stage temperature compensation equalization module and a post-stage driving amplifier module. The temperature compensation equalizer module generates differential voltage related to temperature through a three-stage gallium arsenide diode temperature sensing unit, outputs a control signal through an enhanced FET differential amplification circuit, drives a voltage-controlled attenuation equalizer to dynamically adjust the attenuation amount of a radio frequency signal, and achieves gain stability in a frequency band. Through the collaborative design of a blocking capacitor and a divider resistor, the grid bias of an FET switch is strictly limited in a transconductance linear adjustment interval, and the interval covers 80% of the effective range of the threshold voltage of a gallium arsenide FET tube. The circuit is powered by a single power supply + 5V, stable work of each module is ensured through active bias and a power supply filter network, and the circuit is suitable for extreme temperature environments such as high-frequency communication and radar.

The invention discloses a defect coupling low-noise amplifier. The low-noise amplifier solves the problem that the performance of a low-noise amplifier in the prior art is influenced by a grid source inductance coupling coefficient. Forward coupling of an input inductor and a grid inductor and reverse coupling of the input inductor and a source inductor are achieved through a unique defect coupling transformer matching network, meanwhile, reverse coupling of a grid inductor and the source inductor is achieved, and the coupling coefficient of the grid-source inductor is reduced through coupling counteracting inductance; by combining a differential common-source transconductance amplification stage, a four-order magnetic coupling resonance unit, a differential transconductance amplification stage with a neutralizing capacitor and an output transformer matching network, the characteristics of high gain bandwidth and low noise are realized; simulation and actual tests verify that the low-noise amplifier can effectively reduce the noise coefficient and broaden the input matching range, has good compatibility and wide application prospects based on a conventional integrated circuit production process, can be applied to a phased array system, and can also form a receiver system with other circuits.

The invention discloses a filtering class F power amplifier based on a multimode resonator. The problems of large size and low efficiency caused by common design of a filter and an amplifier are mainly solved. The system comprises an input matching network, a grid electrode direct current feed network, a drain electrode direct current feed network, a transistor, a harmonic suppression network and a filtering matching network, and the input matching network utilizes a pi-shaped circuit to convert standard impedance of an input port into conjugation of optimal source impedance of the transistor; the grid and drain direct-current feed network isolates radio-frequency signals from entering a direct-current power supply and enables the transistor to work at a proper quiescent working point; the harmonic suppression network shapes the drain voltage and current of the transistor; the filtering matching network can control harmonic impedance and participate in matching, so that the drain electrode of the amplifier can reach the optimal load impedance. According to the invention, the loss generated by device connection is obviously reduced, the advantage of low complexity is shown, and the method is suitable for being applied to communication systems such as base stations and radars.

The invention belongs to the technical field of stability compensation circuits, and particularly relates to a stability compensation circuit structure of a high-speed operational amplifier, which is characterized by comprising a function module, a first control module, a second control module, a third control module, a fourth control module and a fourth control module, and the function module comprises an input stage, a differential common-base gain stage, a common-base level converter module and an output stage, and the stability compensation assembly comprises a dual-frequency load unit which is matched with the functional module and comprises a low-frequency load branch and a high-frequency load branch which are connected in parallel. Through the synergistic effect of the double-frequency load unit and the pole regulation and control capacitor, gain segmentation regulation and control of low-frequency high gain and high-frequency fast attenuation are achieved, the open-loop gain of the operational amplifier breaks through the limitation of 30dB of an existing HBT single-stage operational amplifier, and meanwhile the problem that high-frequency phase shift changes too fast is effectively restrained; through simulation verification, the phase margin can reach 67 degrees, the stability requirement of 45-60 degrees and above of an analog circuit is met, and the core contradiction that the high-gain bandwidth and the phase margin of an HBT device are difficult to balance is thoroughly overcome.

The invention discloses a signal processing method and apparatus, an electronic device and a storage medium. The method comprises the steps of obtaining a to-be-processed original signal; inputting the original signal into the target correction model, and determining a correction parameter corresponding to the original signal; the target correction model is used for correcting the original signal on the actual frequency response curve to the target frequency response curve; the target bandwidth of the target frequency response curve is greater than the actual bandwidth of the actual frequency response curve; correcting the original signal based on the correction parameter to obtain a corrected signal; and compensating the corrected signal based on a preset distortion compensation model to obtain a processed signal. In the embodiment of the invention, through a digital signal processing technology, the original signal on the actual frequency response curve is fitted to the target frequency response curve with a larger bandwidth through the target correction model, and then correction distortion compensation is carried out, so that bandwidth expansion of the signal of the existing equipment can be realized.

A broadband Doherty power amplifier is provided, which includes a power divider, a carrier power amplifier circuit, a peak power amplifier circuit, and a load modulation network. The carrier power amplifier circuit includes a carrier input matching circuit, a carrier power amplifier, and a carrier output matching circuit. The peak power amplifier circuit includes a peak input matching circuit, a peak power amplifier and a peak output matching circuit. A resistance value of a system load is ZL. An output impedance of the carrier output matching circuit is Zm and meets Zm=ZL(n+1). An output impedance of the peak output matching circuit is Zp and meets Zp=ZL(n+1) / n. The load modulation network is configured to set an impedance of a combination point to be ZQ, whose resistance value is ZL. A method of implementing a broadband Doherty power amplifier is further provided.

The invention provides an operational amplifier. The operational amplifier comprises a bias module, a chopping module, an enhanced recovery folded cascode module and an output stage module, the enhanced recovery folded cascode module comprises a first input tube group, a second input tube group and a regulation resistor, grid electrodes of the first input tube group and the second input tube group are connected with the output end of the chopping module, a source electrode of the first input tube group is connected to one end of the regulation resistor, a source electrode of the second input tube group is connected to the other end of the regulation resistor, and a source electrode of the second input tube group is connected to the other end of the regulation resistor. The first input tube group and the second input tube group generate different gate-source voltages; the three-path current recovery structure comprises at least two folded node transistors, two circulating current mirror transistors and two shunt transistors, the ratio of the width-to-length ratios of the folded node transistors, the circulating current mirror transistors and the shunt transistors is (1 + x): z (1-x): y (1-x), the value of x is larger than 0 and smaller than 1, and y + z = 1; and the grid electrodes of the matching transistors are connected to the bias voltage provided by the bias module.

The invention discloses a broadband high-power transmitting and receiving circuit and device, and belongs to the field of radio frequency microwaves. When the circuit works in a transmitting state, a radio frequency signal enters from a transmitting input port, enters a power amplifier I and a power amplifier II through a bridge I, enters a bridge II after being amplified by the power amplifier I and the power amplifier II, and is transmitted to a power amplifier II; the load I and the load II are respectively connected to the isolation ends of the electric bridge I and the electric bridge II so as to ensure port impedance matching of the electric bridges; when the radio frequency signal is synthesized into the maximum power through the second bridge and then enters the straight-through port of the high-power coupler for power output, the high-power coupler is in an emission coupling state at the moment, the third load is connected to the output port of the emission coupling branch of the high-power coupler, and the coupled emission signal is absorbed by the third load. And the receiving link is an isolation end of the coupling branch. The problem of receiving and transmitting passive switching of the high-power receiving and transmitting assembly under the ultra wide band can be solved.

The invention discloses a broadband single-ended input differential amplifier, which comprises an unbalanced single-ended to differential input amplification stage, a self-bias feedback balance differential output amplification stage, a broadband feedback differential load network and a broadband feedback path, the unbalanced single-ended to differential input amplification stage is an input stage circuit of the broadband single-ended input differential amplifier, internally comprises a cascaded inverting amplifier, and converts an input signal into a differential intermediate stage signal; the self-biased feedback balance differential output amplification stage is an output stage circuit of the broadband single-ended input differential amplifier, and the differential intermediate stage signal forms a final differential output signal; and the broadband feedback differential load network is connected in parallel to the differential output end of the self-biased feedback balance differential output stage, and feeds back a differential output signal to the unbalanced single-ended to differential input amplification stage through the broadband feedback path to realize bandwidth matching.

The invention provides a reconfigurable network-fused high-efficiency power amplifier and a design method thereof, and a circuit structure comprises an input fundamental wave broadband matching network, an input reconfigurable network, a stabilizing circuit, a biasing circuit, an output harmonic control network, an output fundamental wave broadband matching network and an output reconfigurable network, wherein the input fundamental wave broadband matching adopts conjugate matching and is mainly responsible for optimizing small signal parameters of the circuit; the stabilizing circuit is a lossy network, so that self-oscillation caused by overlarge gain of the circuit is prevented; the biasing circuit provides direct-current voltage for the transistor; and an output fundamental wave broadband matching network in the output matching network adopts power matching and is mainly responsible for optimizing the output power and efficiency of the circuit under a large signal. According to the power amplifier, the reconfigurable network connected with the switching devices is adopted, and switching of the working frequency bands of the power amplifier is controlled. Finally, the harmonic control type reconfigurable high-efficiency power amplifier which can be applied to Bluetooth, Wi-Fi, radar and base station communication is realized.

This disclosure provides systems, methods, and devices for wireless communications that support enhanced two-stage low-noise amplifiers with feedforward circuitry. In a first aspect, a receiver circuit includes a two-stage low-noise amplifier (LNA) configured to amplify a radio frequency (RF) input signal and output a combined amplified RF input signal to a mixer. The two-stage LNA includes a first gain stage configured to amplify the RF input signal and output the amplified RF input signal to a second gain stage of the two-stage LNA and to the mixer via a feedforward path, and includes the second gain stage configured to amplify the amplified RF input signal received from the first gain stage. The two-stage LNA further includes feedforward circuitry in the feedforward path and configured to provide the amplified RF input signal from the first gain stage to the mixer. Other aspects and features are also claimed and described.

Bias circuits for CMOS power amplifiers are provided. The bias circuit includes a feedback module, a first bias module, and a second bias module. The feedback module has a first input connected to a output common mode voltage, a second input connected to a reference voltage, and an output connected to gates of main amplification transistors in a first differential amplification module; based on a difference between the output common mode voltage and the reference voltage, the feedback module adjusts gate voltages of main amplification transistors until the output common mode voltage is equal to the reference voltage; the first bias module provides bias voltages for the first differential amplification module; the second bias module provides bias voltages for a second differential amplification module. The present disclosure adopts direct negative feedback and cascoded current mirrors, which realize accurate DC gate bias and accurate control of the output common mode voltage.

The invention discloses a transimpedance amplifier and an optical receiver, and relates to the technical field of transimpedance amplifiers, the transimpedance amplifier comprises a transimpedance circuit and a post-stage circuit; an input end balancing unit is arranged between the transimpedance circuit and the photoelectric detector; the post-stage circuit is connected with the transimpedance circuit, and a post-stage equalization unit is arranged in the post-stage circuit; the design bandwidth of the post-stage circuit is higher than the target bandwidth of the transimpedance amplifier. According to the invention, the bandwidth of the post-stage circuit is designed to be higher than the target bandwidth of the transimpedance amplifier, and the bandwidth of the transimpedance circuit can be designed to be lower than the target bandwidth required by signal transmission under the condition that the overall bandwidth accords with the target bandwidth of signal transmission, so that lower noise can be obtained. And the bandwidth is improved by combining the two-time equalization expansion of the input end equalization unit and the post-stage equalization unit of the post-stage circuit, so that the characteristics of wide bandwidth and low noise of the whole circuit of the trans-impedance amplifier are realized at the same time on the whole.

It is desirable to increase the output power of an amplifier circuit.SOLUTION: A unit amplifier including a first transistor having a first control terminal to which a first input signal is input and configured to generate a first output signal, a second transistor having a second control terminal to which a second input signal is input and configured to generate a second output signal differential from the first output signal, a third transistor provided in parallel with the first transistor and configured to generate a third output signal differential from the first output signal, and a fourth transistor provided in parallel with the second transistor and configured to generate a fourth output signal differential from the second output signal, the first output signal and the fourth output signal are merged and output to a first output transmission line, and the second output signal and the third output signal are merged and output to a second output transmission line.SELECTED DRAWING: Figure 4