WO2008106822A1 - Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant - Google Patents

Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant Download PDF

Info

Publication number
WO2008106822A1
WO2008106822A1 PCT/CN2007/000708 CN2007000708W WO2008106822A1 WO 2008106822 A1 WO2008106822 A1 WO 2008106822A1 CN 2007000708 W CN2007000708 W CN 2007000708W WO 2008106822 A1 WO2008106822 A1 WO 2008106822A1
Authority
WO
WIPO (PCT)
Prior art keywords
circuit
feedback
sampling
frequency
signal
Prior art date
Application number
PCT/CN2007/000708
Other languages
English (en)
Chinese (zh)
Inventor
Zongshan Zhou
Original Assignee
Zongshan Zhou
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zongshan Zhou filed Critical Zongshan Zhou
Priority to PCT/CN2007/000708 priority Critical patent/WO2008106822A1/fr
Publication of WO2008106822A1 publication Critical patent/WO2008106822A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/34—Negative-feedback-circuit arrangements with or without positive feedback

Definitions

  • the present invention relates to an amplifier, and more particularly to an improved resistor synthesis dual sampling loop negative feedback method and amplifier thereof.
  • Loop negative feedback is an important way to improve the performance of linear amplifiers.
  • the greater the negative feedback depth of the loop the smaller the distortion of the amplifier.
  • increasing the feedback depth is limited by the stability of the amplifier.
  • the higher the frequency of the amplified signal the smaller the loop negative feedback depth that can be obtained, especially in power amplifiers, because high-power devices with poor frequency characteristics must be used.
  • more buffer amplification stages are used and complex changes to the output load are handled. In this way, the higher frequency signal can obtain a smaller negative feedback depth.
  • the audio power amplifier has a feedback depth of only 10 times (20 db) at 20 kHz, so the loop negative feedback has a limited ability to reduce the distortion of the amplifier.
  • the loop feedback instability is caused by: The phase shift of the feedback loop at a certain frequency reaches minus 180 degrees and satisfies the positive feedback condition, and the loop gain at the frequency is greater than 1, so that the self-oscillation is satisfied.
  • the condition produces an oscillation.
  • the use of a dual sampling negative feedback amplifier can improve the stability of the loop negative feedback amplifier, but the negative feedback of the loop sampling reduces the feedback depth of the loop negative feedback, which affects the further improvement of the amplifier performance.
  • the main object of the present invention is to provide an improved resistance synthesis dual sampling loop negative feedback method, which helps to improve the feedback depth.
  • Another object of the present invention is to provide a resistance-synthesized two-channel sampling negative feedback amplifier with good stability and low distortion.
  • the present invention provides an improved resistance synthesis dual sampling loop negative feedback method, comprising the steps of: obtaining a low frequency feedback signal from a low output filter circuit of an amplifier output; The high-frequency feedback signal is obtained in part through a high-pass filter circuit higher than the first-order, and the amplification phases of the two sampling signals are the same; the two sampling signals are synthesized by the resistance synthesis circuit to form a signal with low high-frequency and low-frequency phase shifts. And use this signal for loop negative feedback.
  • the resistance synthesis circuit may connect a high frequency feedback compensation capacitor in parallel with the high frequency sampling resistor, and the high frequency feedback compensation capacitor is connected in parallel with the series attenuation resistor of the high pass filter.
  • the invention relates to a resistance synthesis dual sampling negative feedback amplifier, comprising: a voltage amplifying circuit, outputting a voltage signal and sending it into a cache and an output buffer; an output buffer circuit, a unit voltage gain, providing an amplified output and a low frequency feedback sampling.
  • Low-pass filter circuit input signal high-speed buffer circuit, unit voltage gain, high-pass filter circuit input signal output to high-frequency feedback sampling; low-pass filter circuit, output to low-frequency sampling input terminal of resistance synthesis circuit, used for filtering a high-frequency signal in the low-frequency sampling channel; a high-pass filter circuit higher than the first-order, outputted to the high-frequency sampling input terminal of the resistance synthesis circuit for filtering out the signal of the amplified signal band in the high-frequency sampling channel; the resistance synthesis circuit,
  • the high frequency and low frequency feedback sampling input signals are combined into a composite feedback signal; and a feedback network is input through the feedback network to the inverting input terminal of the voltage amplification stage.
  • the resistance synthesis dual sampling negative feedback amplifier of the invention further comprises a high-pass filter circuit on the high-frequency sampling channel for filtering the signal of the amplified signal band in the high-frequency sampling channel; the low-frequency sampling is used for filtering the low-pass filter
  • the high-frequency signal in the low-frequency sampling channel is to increase the high-frequency stability of the feedback circuit.
  • the filter has a bad influence on the transient performance of the feedback circuit. Increasing the corner frequency of the filter circuit can improve this performance. The system can stabilize the corner frequency as much as possible, or directly use a zero-order low-pass filter circuit, which is equivalent to making the low-pass filter circuit pass through.
  • the resistance synthesis dual sampling negative feedback amplifier output buffer circuit and the high pass filter circuit share a cache circuit; in another embodiment of the invention, the high pass filter circuit is dedicated to a high speed Punch circuit.
  • the resistor synthesis double sampling negative feedback excludes the output buffer from the high frequency feedback loop, so that the high power output buffer stage and the variable load which have a great influence on the feedback depth do not affect the high frequency stability, and only affect the low Frequency stability, so the stability of the feedback circuit is improved, but since the feedback signal is not all taken from the amplifier output, this will reduce the actual feedback depth.
  • the high frequency sampling filtering adopts first-order high-pass filtering
  • the high-frequency sampling filtering adopts high-pass filtering higher than the first order, so the low-frequency signal in the high-frequency sampling is attenuated faster.
  • the low-frequency signal in the composite feedback signal is mainly sampled by the output of the amplifier, so the actual feedback depth of the low frequency band of the resistance synthesis dual-channel sampling negative feedback amplifying circuit can be improved by the invention.
  • FIG. 1 is a schematic block diagram of a first embodiment of a circuit for a resistor-synthesized two-channel sampling negative feedback amplifier according to the present invention
  • FIG. 2 is a first-order ⁇ -pass filter circuit of the first embodiment
  • 3 is a third-order high-pass filter circuit of the first embodiment
  • Figure 5 is a synthesis and feedback network of the first embodiment
  • FIG. 6 is a combination circuit of low pass filtering, high pass filtering, resistance signal synthesis and feedback network of the first embodiment
  • FIG. 7 is an equivalent circuit variation of FIG. 6;
  • Figure 8 is another equivalent circuit variant of Figure 6;
  • FIG. 9 is a schematic block diagram of a circuit embodiment 2 of a resistor-synthesized two-channel sampling negative feedback amplifier according to the present invention
  • FIG. 10 is a schematic block diagram of a third embodiment of a circuit for a resistor-synthesized two-channel sampling negative feedback amplifier according to the present invention.
  • the invention is an improved resistance synthesis dual-channel sampling loop negative feedback method, comprising the following steps: (1) obtaining a low-frequency inverse ⁇ f signal from a low-pass filter circuit of an amplifier output; (2) a high frequency of a large device The low phase shifting part obtains the high frequency feedback signal through the high-pass filter circuit higher than the first order, and (3) the two-way sampling signal is synthesized by the resistance double sampling synthesis circuit to form a signal with low high and low frequency phase shifts. This signal is used for loop negative feedback. Wherein, the two sampling signals have the same amplification phase.
  • the resistance synthesis circuit can connect a high frequency feedback compensation capacitor on the high frequency sampling resistor, and the high pass filter can connect the high frequency feedback compensation capacitor in parallel with the series attenuation resistor to adjust the transient performance of the feedback amplifier and increase High frequency stability.
  • the high frequency sampling filter adopts a high-pass filter circuit higher than the first order, and the method makes the synthesized feedback signal mainly composed of the output end signal in the low-band feedback signal of the amplified signal band, thereby contributing to the improvement of the actual Feedback depth.
  • the higher the order of the high-pass filter the more the actual feedback depth is increased, and the output drive capability of the cache circuit is required to be stronger.
  • the design of such a circuit should be such that the ratio of the signal taken from the amplified output terminal in the synthesized signal of the amplified signal band is high, so that the actual feedback signal is as close as possible to the output signal, and the larger the feedback depth, the higher the ratio should be. To do this, you can use the following two methods:
  • the frequency division frequency of the dual sampling is increased, so that the amplification output end, that is, the low frequency sampling bandwidth is increased, and the method increases the bandwidth requirement of the output stage.
  • a dual sampling synthesis method with fast frequency conversion characteristics is adopted, which can adopt a lower frequency division point, has low bandwidth requirements on the output stage, and has good stability.
  • FIG. 1 is a block diagram of a first embodiment of a circuit of a dual sampling negative feedback amplifier of the present invention.
  • the meanings and uses of each of the symbols are as follows:
  • a voltage amplifying circuit that outputs a voltage signal and feeds it into a cache and an output buffer; in one embodiment, it is a differential input voltage amplification stage.
  • Output buffer circuit unit voltage gain, provides low frequency feedback sampling signal for amplified output and dual sampling synthesis.
  • Low-pass filter circuit filtering high-frequency samples taken from the output of the amplifier
  • 1 5 High-pass filter circuit that filters out the low-frequency components sampled at the output of the cache circuit.
  • the resistance synthesis circuit 16 The resistance synthesis circuit synthesizes the high frequency and low frequency feedback sampling signals into one composite feedback signal.
  • 17 Feedback network, the composite feedback signal is input to the inverting input of the voltage amplification stage through the feedback network.
  • the output of the voltage amplifying circuit 1 is sent to the cache circuit 12, and the output of the cache circuit 12 is sent to the output buffer circuit 13 and the high-pass filter circuit 15 of the high frequency feedback sampling.
  • the output buffer circuit 13 provides the amplified output and the low frequency feedback sampling signal of the low pass filter circuit 14, and the resistance synthesis circuit 16 synthesizes the outputs of the low pass filter circuit 14 and the high pass filter circuit 15 into a single signal.
  • the use of higher-priority filter circuits in high-pass filter circuits is an improvement over the prior art.
  • the existing high-pass filter circuit mostly adopts a first-order filter circuit
  • the present invention adopts a high-order filter circuit to increase the out-of-band attenuation rate of the filter circuit, so that the low-frequency signal outputted to the hybrid circuit is greatly reduced, thereby improving the negative feedback of the Han channel.
  • the working performance of the circuit is very high.
  • B1 is a filter signal input terminal
  • B is a filter signal output point terminal
  • G is an amplifier reference potential
  • RL is usually synthesized by a resistor. The input impedance of the circuit is constructed. ! ⁇ Parallel to, and in series with.
  • a 3 is a third-order high-pass filter circuit according to Embodiment 1 of the present invention, wherein A1 is a filter signal input terminal, A is a filter signal output point terminal, G is an amplifier reference potential, C 2 , C 3 and a capacitor are in an actual circuit.
  • R H is usually composed of the input impedance of the resistance synthesis circuit.
  • Embodiment 4 is a resistance synthesizing circuit according to Embodiment 1 of the present invention, wherein A is a high frequency sampling end, B is a low frequency sampling end, D is a composite output end, and C 5 is a high frequency feedback compensating capacitor, which functions to stabilize high frequency feedback.
  • the actual status of the circuit may not choose the capacitor, resistor R 5.
  • R 6 and for the height adjustment, the composition ratio of the low frequency sampling, a minimum value of 115 and 16 may be zero, at this time combining circuit is a circuit Junction.
  • FIG. 5 is a circuit combining a resistor combining circuit and a feedback circuit network according to Embodiment 1 of the present invention, the circuit is added with a resistor R 7 relative to the resistor combining circuit shown in FIG. 5, wherein A is a high frequency synthesized sampling end, B is the low frequency synthesis sampling terminal, D is the feedback output terminal, and G is the amplifier reference potential. In the amplified signal frequency band, the ratio of the resistance R 5 to the feedback voltage sampling ratio is determined.
  • the low-pass filter circuit, the high-pass filter circuit, the resistance signal synthesis circuit, and the feedback network form a circuit network of two inputs and one output.
  • the circuit network can be designed as a whole, so there may be A variety of equivalent deformation circuits, Figure 6, Figure 7, and Figure 8 are the circuit network and deformation implementation.
  • the low-pass filter in the circuit is a straight-through circuit, which is a zero-order low-pass filter circuit.
  • the high-pass filter is a second-order filter circuit composed of C 2 , ( 3 and composed of the resistor signal synthesis circuit by R 5 , C 5 , composition, C 5 is the high frequency feedback compensation capacitor, the feedback network is composed of R 7 , R 8 , C 6 , C 6 is the high frequency feedback compensation capacitor, A1 is the high frequency sampling input, B1 is the low frequency sampling input, D is Feedback signal output.
  • Figure 8 is a completely equivalent variation of the circuit of Figure 7, replacing the position of the resistor R 5 and its capacitor C 5 in parallel with the capacitor C 3 , at which time the resultant resistor providing high frequency synthesis attenuation is gone, zero Resistance, and the C 3 branch of the high-frequency filter circuit has an attenuation resistor.
  • the attenuation resistor can be connected in series in the C 2 branch.
  • the high-pass filter can be used.
  • the series capacitor has a series high frequency attenuation resistor, and the series high frequency attenuation resistor can also be connected with a high frequency feedback compensation capacitor. That is to say, the high-pass filter circuit can have attenuation, and the attenuation of the high-frequency feedback signal can be shared by the high-pass filter circuit, the resistance synthesis circuit and the feedback network separately or together.
  • the order of the high-pass sampling high-pass filter should be determined according to the design requirements. When the order reaches a certain level, continue to increase the order to improve the actual feedback depth, but increase the output drive capability of the cache circuit. And the complexity of the circuit.
  • the low-frequency sampling uses a low-pass filter to filter out the high-frequency signal in the low-frequency sampling channel in order to increase the high-frequency stability of the feedback circuit.
  • the filter has a bad influence on the transient performance of the feedback circuit, and the filtering circuit is improved.
  • the corner frequency can improve this performance. It can increase the corner frequency as much as possible while keeping the system stable, or directly use a zero-order low-pass filter circuit, which is equivalent to making the low-pass filter circuit pass through.
  • FIG. 9 is a block diagram of a second embodiment of a circuit for a resistively synthesized two-way sampling negative feedback amplifier of the present invention.
  • the two-way sampling loop negative feedback amplifying circuit sets a dedicated high-speed buffer circuit 12 for high-pass filter sampling, and the output of the voltage amplifying circuit 11 is sent to the cache circuit 12 and the output buffer.
  • the circuit 13, the output of the cache circuit 12 is sent to the high-pass filter circuit 15 of the high-frequency feedback sampling, wherein the output buffer circuit 13 provides the amplified output and the low-frequency feedback sampling signal of the low-pass filter circuit 14, the resistance synthesis circuit 16
  • the outputs of the low pass filter circuit 14 and the high pass filter circuit 15 are combined into a single signal which is fed by the feedback network 17 to the inverting input of the voltage amplifying circuit 11 to form a loop feedback.
  • the circuit can reduce the influence of the output buffer circuit 13 on the high frequency feedback sampling, and the stability of the feedback circuit is not affected.
  • the amplifier of this embodiment is an inverting amplifier, so that signal input and feedback are provided.
  • the network is different from the first embodiment.
  • the signal is input by the feedback network 17, and the feedback signal is combined into a signal in the feedback network 17 and output to the inverting input terminal of the voltage amplifying circuit 11, and the output of the voltage amplifying circuit 11 is sent to the cache circuit. 12, the output of the cache circuit 12 is sent to the output buffer circuit 13 and the high-pass filter circuit 15 for high-frequency feedback sampling.
  • the output buffer circuit 13 provides the amplified output and the low frequency feedback sampling signal of the low pass filter circuit 14.
  • the resistance synthesis circuit 16 synthesizes the outputs of the low pass filter circuit 14 and the high pass filter circuit 15 into a single signal, which is fed back by a feedback network.
  • the input signal is combined into one signal and sent to the inverting input terminal of the voltage amplifying circuit 11 to form a loop negative feedback amplification.
  • the circuit can make the actual feedback depth of the resistor synthesis dual-channel sampling loop negative feedback amplifier in the amplified signal band greatly improved, or the amplifier output buffer stage only needs a narrower bandwidth to obtain a smaller feedback depth, depth.
  • the implementation of loop negative feedback is greatly reduced, and the performance of the amplifier circuit is improved.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Amplifiers (AREA)

Abstract

La présente invention concerne un procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance comprenant les étapes suivantes : un signal basse fréquence de rétroaction est obtenu d'une sortie d'un amplificateur à travers un circuit de filtre passe-bas; un signal haute fréquence de rétroaction est obtenu à partir d'une partie haute fréquence déphasée vers le bas de l'amplificateur à travers un circuit de filtre passe-haut dont l'ordre est supérieure à un; un circuit de combinaison de résistance est adapté pour combiner le signal bidirectionnel d'échantillonnage pour former un signal dont le déphasage haute et basse fréquence sont inférieures, et ce signal est utilisé pour une rétroaction négative en boucle. L'invention concerne également un amplificateur à rétroaction négative comportant un circuit de tension amplifiée, un circuit tampon de sortie, un circuit tampon grande vitesse, un circuit de filtre passe-bas; un circuit de filtre passe-haut dont l'ordre est supérieur à un, un circuit de combinaison de résistance et un réseau à rétroaction. Le procédé permet une profondeur de rétroaction supérieure uniquement en utilisant une largeur de bande inférieure et peut donc réduire la difficulté de réaliser une rétroaction négative en boucle profonde.
PCT/CN2007/000708 2007-03-06 2007-03-06 Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant WO2008106822A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2007/000708 WO2008106822A1 (fr) 2007-03-06 2007-03-06 Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2007/000708 WO2008106822A1 (fr) 2007-03-06 2007-03-06 Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant

Publications (1)

Publication Number Publication Date
WO2008106822A1 true WO2008106822A1 (fr) 2008-09-12

Family

ID=39737762

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2007/000708 WO2008106822A1 (fr) 2007-03-06 2007-03-06 Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant

Country Status (1)

Country Link
WO (1) WO2008106822A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109188509A (zh) * 2018-09-21 2019-01-11 西安陆海地球物理科技有限公司 一种检波器低频补偿电路、前置放大电路及其检波器电路
CN114280432A (zh) * 2021-11-24 2022-04-05 浙江新图维电子科技有限公司 一种电缆局放监测设备及方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1327303A (zh) * 2001-02-28 2001-12-19 上海朗鹰科技有限公司 确定频率下提高运算放大器电路稳定性的方法
CN1395364A (zh) * 2001-06-07 2003-02-05 三垦电气株式会社 开关放大器和信号放大方法
CN1741371A (zh) * 2004-08-27 2006-03-01 周宗善 双路取样环路负反馈方法及双路取样负反馈放大器

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1327303A (zh) * 2001-02-28 2001-12-19 上海朗鹰科技有限公司 确定频率下提高运算放大器电路稳定性的方法
CN1395364A (zh) * 2001-06-07 2003-02-05 三垦电气株式会社 开关放大器和信号放大方法
CN1741371A (zh) * 2004-08-27 2006-03-01 周宗善 双路取样环路负反馈方法及双路取样负反馈放大器

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109188509A (zh) * 2018-09-21 2019-01-11 西安陆海地球物理科技有限公司 一种检波器低频补偿电路、前置放大电路及其检波器电路
CN109188509B (zh) * 2018-09-21 2024-04-12 西安陆海地球物理科技有限公司 一种检波器低频补偿电路、前置放大电路及其检波器电路
CN114280432A (zh) * 2021-11-24 2022-04-05 浙江新图维电子科技有限公司 一种电缆局放监测设备及方法
CN114280432B (zh) * 2021-11-24 2023-10-13 浙江新图维电子科技有限公司 一种电缆局放监测设备及方法

Similar Documents

Publication Publication Date Title
WO2006021142A1 (fr) Procede de contre-reaction en boucle a double d'echantillonnage et amplificateur a contre-reaction a double echantillonnage
EP2553810B1 (fr) Système et procédé pour limiter la course d'un haut-parleur audio
JPH0974320A (ja) 定振幅波合成型電力増幅回路
JP5801477B2 (ja) 電流バッファ
US10931247B2 (en) Chopper amplifier
WO2008106822A1 (fr) Procédé de rétroaction négative en boucle d'échantillonnage double combinaison de résistance et amplificateur correspondant
CN109714681A (zh) 一种采样率自适应的数字音频3d和混音效果的装置及其实现方法
JP2013251746A (ja) コンデンサマイクロホン
WO2023216846A1 (fr) Circuit d'amplification de puissance doherty et module frontal radiofréquence
US20050210092A1 (en) Variable passband autoregressive moving average filter
US9112480B2 (en) Multi-mode audio amplifiers
US9887688B2 (en) Filter assembly and a method of filtering
US20060049869A1 (en) Digital amplifier and methods for enhancing resolution and dynamic range of a digital amplifier
JP6102360B2 (ja) チャンネルデバイダおよびこれを含む音声再生システム
EP2562929A1 (fr) Procédé pour un amplificateur de gain élevé au moyen de résistances de faible valeur
US20200212945A1 (en) Split frequency band signal paths for signal sources
CN113965197A (zh) 一种rtr分频方法及电路
JP5424396B2 (ja) ドップラ歪補償機能を有する増幅装置
JP2003032082A (ja) デジタルフィルタ
CN101442325B (zh) 具有带通滤波功能的放大器
JP6015161B2 (ja) チャンネルデバイダおよびこれを含む音声再生システム
JPH01176105A (ja) 非直線歪補償回路
RU51807U1 (ru) Многоканальное широкополосное усилительное устройство
KR101363302B1 (ko) 부궤환 회로 적용 음향증폭기
WO2021260828A1 (fr) Amplificateur de doherty

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07720329

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC - EPO FORM 1205A SENT ON 22.12.2009

122 Ep: pct application non-entry in european phase

Ref document number: 07720329

Country of ref document: EP

Kind code of ref document: A1