CN218450050U - Amplifiers and Oscilloscopes - Google Patents

Abstract

The utility model discloses an amplifier and oscilloscope. The amplifier includes: the device comprises an input amplification module, an isolation module, a feedforward transconductance module, a first current buffer module, a first current source module and a second current source module; the input amplification module and the isolation module are connected in series between the first current source module and the output end of the amplifier; the feedforward transconductance module and the first current buffer module are connected in series between the second current source module and the output end of the amplifier; wherein, the input control end pair is accessed to the input signal pair; the feedforward transconductance module comprises a feedforward control end pair, and the feedforward control end pair is electrically connected with the first node pair in a staggered manner; the isolation module comprises an isolation control end pair, and the isolation control end pair is connected with a first reference voltage; the first current buffer module comprises a first buffer control end pair, and the first buffer control end pair is connected with a second reference voltage. Compared with the prior art, the embodiment of the utility model provides a direct current linearity of amplifier has been promoted.

Description

Amplifiers and Oscilloscopes

technical field

The utility model relates to the technical field of circuits, in particular to an amplifier and an oscilloscope.

Background technique

An oscilloscope is an instrument used to measure alternating current or pulse current waveforms. It can convert electrical signals into visible images, and all periodic physical processes that can be transformed into electrical effects can be observed with an oscilloscope, which is convenient for people to study the changing process of various electrical phenomena.

In the prior art, an oscilloscope needs to set an amplifier as an analog front-end amplifier of the oscilloscope. However, the amplifier has the problem of nonlinear distortion, which is also called waveform distortion and nonlinear distortion, and the output signal is not linearly related to the input signal. In an ideal amplifier, the output signal should faithfully reflect the input signal, that is, the output signal and the input signal can be different in amplitude and delayed in time, but the waveform should be the same. However, in the prior art, due to process fluctuations and other reasons, there are differences in the waveforms of the output signal and the input signal, and this phenomenon is called distortion.

In applications that require relatively high DC linearity of amplifiers, such as: oscilloscope analog front-end amplifiers, signal source analog front-end amplifiers, power audio amplifiers, etc., existing amplifiers cannot meet the requirements for DC linearity.

Utility model content

The utility model provides an amplifier and an oscilloscope to improve the DC linearity of the amplifier.

According to one aspect of the present invention, an amplifier is provided, including: an input amplification module, an isolation module, a feedforward transconductance module, a first current buffer module, a first current source module, and a second current source module;

The input amplification module and the isolation module are connected in series between the first current source module and the output terminal of the amplifier; wherein, the connection point defining the input amplification module and the isolation module is a first node pair ;

The feedforward transconductance module and the first current buffer module are connected in series between the second current source module and the output terminal of the amplifier;

Wherein, the input amplification module includes a pair of input control terminals, and the pair of input control terminals is connected to an input signal pair; the feedforward transconductance module includes a pair of feedforward control terminals, and the pair of feedforward control terminals is connected to the first A node pair is electrically connected in a staggered manner; the isolation module includes a pair of isolation control terminals, and the pair of isolation control terminals is connected to a first reference voltage; the first current buffer module includes a pair of first buffer control terminals, and the first buffer The control terminal is connected to the second reference voltage.

Optionally, the first current buffer module includes at least one level of current buffer.

Optionally, the amplifier also includes:

A second current buffer module, the second current buffer module is connected in series between the isolation module and the output terminal of the amplifier; the second current buffer module includes a second buffer control terminal pair, the second buffer control The terminal pair is connected to the third reference voltage;

Wherein, the second current buffer module includes a primary current buffer.

Optionally, the amplifier also includes:

A third current buffer module, the third current buffer module is connected in series between the second current buffer module and the output terminal of the amplifier; defining the connection between the third current buffer module and the second current buffer module The point is the second node pair, the feedforward transconductance module and the first current buffer module are connected in series between the second current source module and the second node pair; the third current buffer module includes the first Three buffer control terminal pairs, the third buffer control terminal pair connected to the fourth reference voltage;

Wherein, the third current buffer module includes a primary current buffer.

Optionally, the current buffer includes: a first transistor and a second transistor, the control terminal of the first transistor and the control terminal of the second transistor are connected to the same reference voltage; the second transistor of the first transistor One terminal and the first terminal of the second transistor are used as the input connection point pair of the current buffer; the second terminal of the first transistor and the second terminal of the second transistor are used as the current buffer Output connection point pairs.

Optionally, both the first transistor and the second transistor are triodes; or, both the first transistor and the second transistor are field effect transistors.

Optionally, the input amplification module includes a pair of connection points connected to the first current source module; the feedforward transconductance module includes a pair of connection points connected to the second current source module;

The first current source module includes: a first current source, the current input terminal of the first current source is electrically connected to the connection point of the input amplification module, and the current output terminal of the first current source is connected to the first supply voltage electrical connection;

And/or, the second current source module includes: a second current source, the current input terminal of the second current source is electrically connected to the connection point pair of the feedforward transconductance module, and the second current source The current output terminal is electrically connected with the second power supply voltage.

Optionally, the input amplification module includes a first connection point and a second connection point connected to the first current source module; the feedforward transconductance module includes a third connection point connected to the second current source module a connection point and a fourth connection point;

The first current source module includes: a first current source, a first resistance unit and a second resistance unit, and the current input terminal of the first current source is connected in series with the first connection point of the input amplification module. The first resistance unit, the second resistance unit is connected in series between the current input end of the first current source and the second connection point of the input amplification module, the current output end of the first current source is connected to the first power supply voltage electrical connection;

And/or, the second current source module includes: a second current source, a third resistance unit and a fourth resistance unit, the current input end of the second current source is connected to the third connection of the feedforward transconductance module The third resistance unit is connected in series between the points, the fourth resistance unit is connected in series between the current input terminal of the second current source and the fourth connection point of the feedforward transconductance module, and the second current source The current output end of the current output terminal is electrically connected with the second power supply voltage.

Optionally, the input amplification module includes a first connection point and a second connection point connected to the first current source module; the feedforward transconductance module includes a third connection point connected to the second current source module a connection point and a fourth connection point;

The first current source module includes: a third current source, a fourth current source and a fifth resistance unit, the current input end of the third current source is electrically connected to the first connection point, and the fourth current source The current input end of the current source is electrically connected to the second connection point of the input amplification module; the fifth resistance unit is also connected between the current input end of the third current source and the current input end of the fourth current source, The current output end of the third current source is electrically connected to the third power supply voltage, and the current output end of the fourth current source is electrically connected to the fourth power supply voltage;

And/or, the second current source module includes: a fifth current source, a sixth current source and a sixth resistance unit, the current input end of the fifth current source is electrically connected to the third connection point, the The current input end of the sixth current source is electrically connected to the fourth connection point of the input amplification module; the current input end of the fifth current source is also connected to the current input end of the sixth current source. In the six-resistor unit, the current output end of the fifth current source is electrically connected to the fifth power supply voltage, and the current output end of the sixth current source is electrically connected to the sixth power supply voltage.

According to another aspect of the present utility model, an oscilloscope is provided, including: the amplifier according to any embodiment of the present utility model; wherein, the input terminal of the amplifier is used as the input terminal of the oscilloscope.

In the technical scheme of the embodiment of the utility model, on the basis of the original input amplification module A1 of the amplifier, an isolation module C1, a feed-forward transconductance module D1 and a first current buffer module B1 are added; so that the amplifier includes the main branch that generates the original current Road 1 and main branch 2, and also includes compensation branch 1 and compensation branch 2 that generate compensation current. Since the nonlinear compensation generated by the compensation branch 1 is input to the main branch 2, and the nonlinear compensation generated by the compensation branch 2 is input to the main branch 1, the original current in each branch and the nonlinearity generated by the compensation current are opposite phases of. Therefore, the nonlinearity generated by the main branch and the nonlinearity generated by the compensation branch are superimposed and cancel each other out, and the output current has relatively good nonlinearity, which improves the DC linearity of the amplifier. And, the current output by the feedforward transconductance module passes through the first current buffer module, which increases the output impedance of the feedforward transconductance module, and reduces the Miller effect of the feedforward control terminal to the output terminal of the amplifier, thereby increasing the output of the amplifier. The bandwidth of the overall circuit further improves the DC linearity of the amplifier.

It should be understood that the content described in this section is not intended to identify key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other characteristics of the present invention will be easily understood through the following description.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some implementations of the present invention. For example, those of ordinary skill in the art can also obtain other drawings based on these drawings on the premise of not paying creative efforts.

Fig. 1 is the schematic circuit diagram of a kind of amplifier that the utility model embodiment provides;

Fig. 2 is a schematic structural diagram of a current buffer provided by an embodiment of the present invention;

Fig. 3 is the schematic circuit diagram of another kind of amplifier that the utility model embodiment provides;

4 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention;

5 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention;

6 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention;

7 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention;

FIG. 8 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the utility model. Obviously, the described The embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

It should be noted that the terms "first" and "second" in the specification and claims of the present utility model and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific order or sequence . It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device comprising a sequence of steps or elements is not necessarily limited to the expressly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.

The embodiment of the utility model provides an amplifier, which can improve the problem of nonlinear distortion and improve DC linearity, and is suitable for oscilloscope analog front-end amplifiers, signal source analog front-end amplifiers, power audio amplifiers, etc., which require relatively high DC linearity occasions. FIG. 1 is a schematic circuit diagram of an amplifier provided by an embodiment of the present invention. Referring to FIG. 1, the amplifier includes: an input amplification module A1, an isolation module C1, a feedforward transconductance module D1, a first current buffer module B1, a first current source module 10 and a second current source module 20;

The input amplification module A1 and the isolation module C1 are connected in series between the output terminal of the first current source module 10 and the amplifier; wherein, the connection point defining the input amplification module A1 and the isolation module C1 is the first node pair; wherein, the first node pair Including node JD1 and node JD2; the output terminal of the amplifier includes node ION and node IOP;

The feed-forward transconductance module D1 and the first current buffer module B1 are connected in series between the second current source module 20 and the output terminal of the amplifier;

The input amplification module A1 includes an input control terminal pair, wherein the input control terminal pair includes a node VIP and a node VIN; an input control terminal pair (including a node VIP and a node VIN) is connected to an input signal pair (including a positive phase input signal and an inversion input Signal);

The feedforward transconductance module D1 includes a feedforward control terminal pair, and the feedforward control terminal pair is electrically connected to the first node pair (including node JD1 and node JD2); the isolation module C1 includes an isolation control terminal pair, and the isolation control terminal pair is connected to The first reference voltage vb1; the first current buffer module B1 includes a first pair of buffer control terminals connected to the second reference voltage vb2.

Among them, the corresponding electrical connection between the node VIP, the node JD1 and the node ION belongs to the same branch, which is defined as the main branch 1; the corresponding electrical connection between the node VIN, the node JD2 and the node IOP belongs to the same branch, and the definition Main branch 2. The feedforward transconductance module D1 and the first current buffer module B1 generate a nonlinear compensation current under the control of the first node pair (including the node JD1 and the node JD2 ), including the compensation branch 1 and the compensation branch 2 . It is defined that the compensation branch 1 is electrically connected to the node IOP, and the compensation branch 2 is electrically connected to the node ION. The feedforward control terminal pair of the feedforward transconductance module D1 is electrically connected with the first node pair (including the node JD1 and the node JD2) in an interleaved manner, which means that the compensation branch 1 is electrically connected with the node JD1 and is controlled by the node JD1; the compensation branch 2 It is electrically connected with node JD2 and controlled by node JD2.

Exemplarily, the working principle of the amplifier is as follows: the input signal is converted into the original current through the input amplification module A1; the original current is output through the isolation module C1. However, due to the process deviation of the amplification module A1, the original current has a non-linear problem. The feedforward transconductance module D1 amplifies the voltage of the first node pair (including the node JD1 and the node JD2 ), which is equivalent to sampling and amplifying the nonlinearity of the input amplification module A1 . The feed-forward transconductance module D1 converts the nonlinearity into a compensation current, and the compensation current is output through the first current buffer module B1. The original current and the compensation current converge at the output of the amplifier (including the node ION and the node IOP). Specifically, the original current in the main branch 1 and the compensation current in the compensation branch 2 converge; the original current in the main branch 2 Combined with the compensation current in compensation branch 1.

In this way, since the nonlinear compensation generated by the compensation branch 1 is input to the main branch 2, and the nonlinear compensation generated by the compensation branch 2 is input to the main branch 1, the original current in each branch and the nonlinear compensation generated by the compensation current are reversed. Therefore, the nonlinearity generated by the main branch and the nonlinearity generated by the compensation branch are superimposed and cancel each other out, and the output current has relatively good nonlinearity, which improves the DC linearity of the amplifier. And, the current output by the feedforward transconductance module D1 passes through the first current buffer module B1, which increases the output impedance of the feedforward transconductance module D1, and reduces the feedforward control terminal pair (ie, node JD1 and node JD2) to The Miller effect of the output terminal of the amplifier (including the node ION and the node IOP) increases the bandwidth of the overall circuit of the amplifier and further improves the DC linearity of the amplifier.

On the basis of the foregoing embodiments, optionally, the first current buffer module B1 includes at least one level of current buffer. FIG. 2 is a schematic structural diagram of a current buffer provided by an embodiment of the present invention. Referring to FIG. 2, optionally, the current buffer includes: a first transistor Q10 and a second transistor Q20, the control terminal of the first transistor Q10 and the control terminal of the second transistor Q20 are connected to the same reference voltage vb; the first transistor Q10 The first terminal of the first transistor Q20 and the first terminal of the second transistor Q20 serve as the input connection point pair of the current buffer; the second terminal of the first transistor Q10 and the second terminal of the second transistor Q20 serve as the output connection point pair of the current buffer.

Continue referring to FIG. 2 , optionally, both the first transistor Q10 and the second transistor Q20 are triodes. Specifically, the base of the first transistor Q10 and the base of the second transistor Q20 are both connected to the same reference voltage vb, the collector of the first transistor Q10 is electrically connected to the node IOP, and the first transistor Q10 and the second transistor Q20 are respectively Connect in series in the branch circuit that needs to adjust the output impedance.

In other embodiments, both the first transistor Q10 and the second transistor Q20 may be set to be field effect transistors, and their implementation principles are similar, so details are not repeated here.

On the basis of the above embodiments, optionally, the input amplification module A1 , the isolation module C1 , the feedforward transconductance module D1 and the first current buffer module B1 are all provided with transistor pairs, which will be described in detail below. FIG. 3 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to FIG. 3 , on the basis of the foregoing embodiments, optionally, both the isolation module C1 and the first current buffer module B1 include a first-stage current buffer. The isolation module C1 includes a transistor Q11 and a transistor Q21, and the first current buffer module B1 includes a transistor Q12 and a transistor Q22. The input amplification module A1 includes a transistor Q31 and a transistor Q32, and the feedforward transconductance module D1 includes a transistor Q41 and a transistor Q42.

The base of the transistor Q31 is electrically connected to the node VIP, the emitter of the transistor Q31 is electrically connected to the first current source module 10 , and the collector of the transistor Q31 is electrically connected to the node JD1 . The base of the transistor Q32 is electrically connected to the node VIN, the emitter of the transistor Q32 is electrically connected to the first current source module 10, and the collector of the transistor Q32 is electrically connected to the node JD2.

The base of the transistor Q11 is electrically connected to the reference voltage vb1, the emitter of the transistor Q11 is electrically connected to the node JD1, and the collector of the transistor Q11 is electrically connected to the node ION. The base of the transistor Q21 is electrically connected to the reference voltage vb1, the emitter of the transistor Q21 is electrically connected to the node JD2, and the collector of the transistor Q21 is electrically connected to the node IOP.

The base of the transistor Q41 is electrically connected to the node JD1, the emitter of the transistor Q41 is electrically connected to the second current source module 20, the collector of the transistor Q41 is electrically connected to the emitter of the transistor Q12, and the collector of the transistor Q12 is electrically connected to the node IOP . The base of the transistor Q42 is electrically connected to the node JD2, the emitter of the transistor Q42 is electrically connected to the second current source module 20, the collector of the transistor Q42 is electrically connected to the emitter of the transistor Q22, and the collector of the transistor Q22 is electrically connected to the node ION . Both the bases of the transistor Q12 and the transistor Q22 are electrically connected to the reference voltage vb2.

Exemplarily, the operating principle of the amplifier is that the input signal is converted into an original current through the transistor Q31 and the transistor Q32, and the original current will be non-linear due to process deviation. The original current is output through the transistor Q11 and the transistor Q21. The transistor Q41 and the transistor Q42 amplify the emitter voltage of the transistor Q11 and the transistor Q21, and sample the non-linearity of the transistor Q31 and the transistor Q32, and further amplify to generate a compensation current. The compensation current passes through the primary current buffer formed by the transistor Q12 and the transistor Q22, which increases the output impedance of the branch circuit of the transistor Q41 and the transistor Q42, and the current buffer can reduce the base of the transistor Q41 and the transistor Q42 to the node IOP, node ION's Maitreya effect, thereby increasing the overall circuit bandwidth.

Transistor Q12 and transistor Q22 input the converted compensation current to transistor Q21 and transistor Q11 current branch. In this way, since the nonlinear compensation generated by the transistor Q41 is input to the terminal of the transistor Q32, and the nonlinear compensation generated by the transistor Q42 is input to the terminal of the transistor Q31, the nonlinear compensation generated by the original current and the compensation current are in opposite phases. Therefore, the non-linearity generated by the transistor Q31 and the transistor Q32 and the non-linearity generated by the transistor Q41 and the transistor Q42 are superimposed and cancel each other out, and the output current has relatively good non-linearity.

Fig. 4 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to Fig. 4, on the basis of the above-mentioned embodiments, optionally, the amplifier further includes: a second current buffer module B2, the second current buffer module B2 is connected in series with the output terminal of the isolation module C1 and the amplifier (including the node ION and the node between IOP); the second current buffer module B2 includes a second pair of buffer control terminals connected to the third reference voltage vb3. Wherein, the second current buffer module B2 includes a first-level current buffer, and its specific structure can be set with reference to the foregoing embodiments. Exemplarily, the second current buffer module B2 includes a transistor Q13 and a transistor Q23, the bases of the transistor Q13 and the transistor Q23 are connected to the third reference voltage vb3, the transistor Q13 is connected in series between the collector of the transistor Q11 and the node ION, and the transistor Q23 connected in series between the collector of transistor Q21 and node IOP.

The embodiment of the utility model is set in this way, which is equivalent to connecting the output terminals of the transistor Q11 and the transistor Q21 with one-stage or multi-stage current buffers. Since in this circuit structure, the node ION and the node IOP are the confluence points of two currents (the original current and the compensation current), the output impedance seen from the node ION and the node IOP is the parallel connection of the output impedance of the two branches, which will affect the circuit The size of the bandwidth. Therefore, adding the second current buffer module B2 in the embodiment of the present utility model is beneficial to increase the output impedance of the circuit and increase the bandwidth of the circuit.

FIG. 5 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to FIG. 5 , on the basis of the above embodiments, optionally, the amplifier further includes: a third current buffer module B3, the third current buffer module B3 is connected in series between the second current buffer module B2 and the output terminal of the amplifier; Define the connection point of the third current buffer module B3 and the second current buffer module B2 as the second node pair (including node J1 and node J2), and the feedforward transconductance module D1 and the first current buffer module B1 are connected in series with the second current source Between the module 20 and the second node pair, that is, the node J1 and the node J2 are the confluence points of the original current and the compensation current; the third current buffer module B3 includes a third buffer control terminal pair, and the third buffer control terminal pair is connected to the fourth Reference voltage vb4. Wherein, the third current buffer module B3 includes a first-stage current buffer, and its specific structure can be set with reference to the foregoing embodiments. Exemplarily, the third current buffer module B3 includes a transistor Q14 and a transistor Q24, the bases of the transistor Q14 and the transistor Q24 are connected to the fourth reference voltage vb4, the transistor Q14 is connected in series between the node J1 and the node ION, and the transistor Q23 is connected in series with the node Between J2 and the node IOP.

The embodiment of the utility model is set in this way, which is equivalent to connecting a one-stage or multi-stage current buffer at the confluence point of the original current and the compensation current. Specifically, the transistor Q12 and the transistor Q22 form a first-level current buffer, which increases the output impedance of the transistor Q41 and the transistor Q42 branch, and the current buffer can reduce the voltage from the base of the transistor Q41 and the transistor Q42 to the nodes J1 and J2. The Maitreya effect, thereby increasing the bandwidth of the overall circuit. The parasitic capacitance and parallel impedance of the two branches can be seen from the nodes J1 and J2, which will affect the size of the bandwidth. The current is output through the third current buffer module B3, which increases the output impedance while reducing the output terminal (nodes ION and node IOP) parasitic capacitance, thereby increasing the circuit bandwidth.

Fig. 6 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to FIG. 6, on the basis of the above-mentioned embodiments, optionally, the input amplification module A1 includes a connection point pair (including the first connection point JD3 and the second connection point JD4) connected to the first current source module 10; The feeding transconductance module D1 includes a connection point pair (including the third connection point JD5 and the fourth connection point JD6) connected with the second current source module 20; the first current source module 10 includes: the first current source IS1, the first current source The current input terminal of the source IS1 is electrically connected to the connection point pair (including the first connection point JD3 and the second connection point JD4) of the input amplification module A1, and the current output terminal of the first current source IS1 is electrically connected to the first power supply voltage; and /Or, the second current source module 20 includes: the second current source IS2, the connection point pair between the current input end of the second current source IS2 and the feedforward transconductance module D1 (including the third connection point JD5 and the fourth connection point JD6 ) is electrically connected, and the current output end of the second current source IS2 is electrically connected to the second power supply voltage. Wherein, the amplifier constituted by the first current source IS1 is a common-source amplifier input.

On the basis of the foregoing embodiments, it can be understood that only when the non-linearities generated by the transistors Q31 and Q32 are equal to the non-linearities generated by the transistors Q41 and Q42 can they be completely canceled. However, in practical applications, as the process fluctuates, the DC linearity generated by the two cannot be completely offset, so the second current source IS2 can be set as an adjustable current source, and the current of the second current source IS2 can be adjusted so that the transistor The non-linearity of Q41 and transistor Q42 can be adjusted to compensate for process fluctuations.

FIG. 7 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to FIG. 7 , on the basis of the above embodiments, optionally, the input amplification module A1 includes a first connection point JD3 and a second connection point JD4 connected to the first current source module 10; the feedforward transconductance module D1 includes The third connection point JD5 and the fourth connection point JD6 connected with the second current source module 20; the first current source module 10 includes: a first current source IS1, a first resistance unit R1 and a second resistance unit R2, the first current The first resistance unit R1 is connected in series between the current input terminal of the source IS1 and the first connection point JD3 of the input amplification module A1, and the first resistance unit R1 is connected in series between the current input terminal of the first current source IS1 and the second connection point JD4 of the input amplification module A1. Two resistance units R2, the current output terminal of the first current source IS1 is electrically connected to the first power supply voltage; and/or, the second current source module 20 includes: the second current source IS2, the third resistance unit R3 and the fourth resistance unit R4, the second current source IS2 is an adjustable current source, the third resistance unit R3 is connected in series between the current input terminal of the second current source IS2 and the third connection point JD5 of the feedforward transconductance module D1, the second current source IS2 A fourth resistor unit R4 is connected in series between the current input terminal and the fourth connection point JD6 of the feedforward transconductance module D1, and the current output terminal of the second current source IS2 is electrically connected to the second power supply voltage. Wherein, the amplifier composed of the first current source IS1, the first resistance unit R1 and the second resistance unit R2 is an input of a degenerate resistance amplifier. In the embodiment of the utility model, a resistance unit is added in the current source module, which is beneficial to improve the linearity of the current source module.

FIG. 8 is a schematic circuit diagram of another amplifier provided by the embodiment of the present invention. Referring to FIG. 8 , on the basis of the above embodiments, optionally, the first current source module 10 includes: a third current source IS3, a fourth current source IS4 and a fifth resistance unit R5, the current of the third current source IS3 The input end is electrically connected to the first connection point JD3, and the current input end of the fourth current source IS4 is electrically connected to the second connection point JD4 of the input amplification module A1; the current input end of the third current source IS3 and the fourth current source IS4 The fifth resistance unit R5 is also connected between the current input ends, the current output end of the third current source IS3 is electrically connected to the third power supply voltage, and the current output end of the fourth current source IS4 is electrically connected to the fourth power supply voltage; and/or , the second current source module 20 includes: a fifth current source IS5, a sixth current source IS6 and a sixth resistance unit R6, the current input end of the fifth current source IS5 is electrically connected to the third connection point JD5, the sixth current source IS6 The current input end of the current source is electrically connected to the fourth connection point JD6 of the input amplification module A1; the sixth resistance unit R6 is also connected between the current input end of the fifth current source IS5 and the current input end of the sixth current source IS6, and the fifth current The current output terminal of the source IS5 is electrically connected to the fifth power supply voltage, and the current output terminal of the sixth current source IS6 is electrically connected to the sixth power supply voltage. Wherein, the amplifier formed by the third current source IS3, the fourth current source IS4 and the fifth resistance unit R5 is the input of the degenerate resistance amplifier. In the embodiment of the utility model, a resistance unit is added in the current source module, which is beneficial to improve the linearity of the current source module. In addition, for the structure shown in FIG. 7 , two resistors are set in each current source module, and the two resistors need to be matched. For the structure shown in FIG. 8 , a resistor is set in each current source module, and there is no matching problem, so the offset voltage performance of the structure shown in FIG. 8 is better. And, in the current source module shown in FIG. 8 , the resistor is across the emitter of the input transistor, and no extra voltage is consumed on the resistor, so the input range is larger.

The embodiment of the utility model also provides an oscilloscope, which includes: the amplifier provided in any of the above embodiments; wherein, the input end of the amplifier is used as the input end of the oscilloscope. The oscilloscope provided in this embodiment has the beneficial effect of the amplifier provided in any of the above embodiments, which will not be repeated here.

It should be understood that steps may be reordered, added or deleted using the various forms of flow shown above. For example, each step described in the utility model can be executed in parallel or sequentially or in a different order, as long as the desired result of the technical solution of the utility model can be achieved, there is no limitation herein.

The above specific implementation methods do not constitute a limitation to the protection scope of the present utility model. It should be apparent to those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made depending on design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims (10)

1. An amplifier, comprising: the device comprises an input amplification module, an isolation module, a feedforward transconductance module, a first current buffer module, a first current source module and a second current source module;

the input amplification module and the isolation module are connected in series between the first current source module and the output end of the amplifier; wherein a connection point of the input amplification module and the isolation module is defined as a first node pair;

the feed-forward transconductance module and the first current buffer module are connected in series between the second current source module and the output end of the amplifier;

the input amplification module comprises an input control end pair, and the input control end pair is connected with an input signal pair; the feedforward transconductance module comprises a feedforward control end pair, and the feedforward control end pair is electrically connected with the first node pair in a staggered manner; the isolation module comprises an isolation control end pair, and the isolation control end pair is connected with a first reference voltage; the first current buffer module comprises a first buffer control end pair, and the first buffer control end pair is connected with a second reference voltage.

2. The amplifier of claim 1, wherein the first current buffer module comprises at least one stage of current buffer.

3. The amplifier of claim 1, further comprising:

a second current buffer module connected in series between the isolation module and the output of the amplifier; the second current buffer module comprises a second buffer control end pair, and the second buffer control end pair is connected with a third reference voltage;

wherein the second current buffer module comprises a primary current buffer.

4. The amplifier of claim 3, further comprising:

the third current buffer module is connected between the second current buffer module and the output end of the amplifier in series; defining a connection point of the third current buffer module and the second current buffer module as a second node pair, the feed forward transconductance module and the first current buffer module being connected in series between the second current source module and the second node pair; the third current buffer module comprises a third buffer control end pair, and the third buffer control end pair is connected with a fourth reference voltage;

wherein the third current buffer module comprises a primary current buffer.

5. The amplifier according to any of claims 2-4, wherein the current buffer comprises: the control end of the first transistor and the control end of the second transistor are connected with the same reference voltage; a first end of the first transistor and a first end of the second transistor are used as an input connecting point pair of the current buffer; the second end of the first transistor and the second end of the second transistor serve as an output connecting point pair of the current buffer.

6. The amplifier according to claim 5, wherein the first transistor and the second transistor are both transistors; or, the first transistor and the second transistor are both field effect transistors.

7. The amplifier of claim 1, wherein the input amplification module comprises a pair of connection points connected to the first current source module; the feed-forward transconductance module comprises a connecting point pair connected with the second current source module;

the first current source module includes: the current input end of the first current source is electrically connected with the connecting point pair of the input amplification module, and the current output end of the first current source is electrically connected with a first power supply voltage;

and/or, the second current source module comprises: and the current input end of the second current source is electrically connected with the connecting point pair of the feedforward transconductance module, and the current output end of the second current source is electrically connected with a second power voltage.

8. The amplifier of claim 1, wherein the input amplification module comprises a first connection point and a second connection point connected to the first current source module; the feed-forward transconductance module comprises a third connection point and a fourth connection point which are connected with the second current source module;

the first current source module includes: the current output end of the first current source is electrically connected with a first power voltage;

and/or, the second current source module comprises: the feed-forward transconductance module is connected with the feed-forward transconductance module in series, and the feed-forward transconductance module is connected with the feed-forward transconductance module in series.

9. The amplifier of claim 1, wherein the input amplification module comprises a first connection point and a second connection point connected to the first current source module; the feed-forward transconductance module comprises a third connection point and a fourth connection point which are connected with the second current source module;

the first current source module includes: the current input end of the third current source is electrically connected with the first connection point, and the current input end of the fourth current source is electrically connected with the second connection point of the input amplification module; the fifth resistance unit is further connected between the current input end of the third current source and the current input end of the fourth current source, the current output end of the third current source is electrically connected with a third power supply voltage, and the current output end of the fourth current source is electrically connected with a fourth power supply voltage;

and/or, the second current source module comprises: the current input end of the fifth current source is electrically connected with the third connection point, and the current input end of the sixth current source is electrically connected with the fourth connection point of the input amplification module; and the current output end of the fifth current source is electrically connected with a fifth power supply voltage, and the current output end of the sixth current source is electrically connected with a sixth power supply voltage.

10. An oscilloscope, comprising: an amplifier as claimed in any one of claims 1 to 9; and the input end of the amplifier is used as the input end of the oscilloscope.

Images