Amplifier and oscilloscope

Abstract

An amplifier, comprising a transconductance amplification module (100), a feedforward transconductance module (200) and a gain control module (300), wherein an input control end pair (101P, 101N) of the transconductance amplification module (100) is connected to an input signal pair (VIP, VIN), and the transconductance amplification module (100) is configured to convert the input signal pair (VIP, VIN) into an output current pair (IOP, ION) and output same; a first feedforward control end pair (201P, 201N) comprised in the feedforward transconductance module (200) is connected to the input signal pair (VIP, VIN) and outputs a feedforward current pair; the gain control module (300) comprises a first differential pair (301) and a second differential pair (302), and a first output end (302P) and second output end (303P) of the first differential pair (301) are respectively configured to compensate for a non-inverting output current and inverting output current in the output current pair; and a first output end (302N) and second output end (303N) of the second differential pair (302) are respectively configured to compensate for the non-inverting output current and inverting output current in the output current pair.

Description

Amplifier and oscilloscope

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 23, 2024, with application number 202410199737.4, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of circuit technology, for example, to an amplifier and an oscilloscope. Background Art

[0003] High-bandwidth amplifiers are commonly used in systems that need to process high-frequency signals, such as oscilloscope analog front ends and probe analog front ends. In these circuits, high-bandwidth amplifiers maintain high gain and frequency response for high-frequency signals. However, the high-frequency response of high-bandwidth amplifiers in related art is significantly affected by chip and printed circuit board (PCB) manufacturing processes. This process variation can lead to inconsistent frequency responses between amplifier batches, which may not meet user requirements.

[0004] Summary of the Invention

[0005] The present application provides an amplifier and an oscilloscope to eliminate process deviations.

[0006] According to one aspect of the present application, an amplifier is provided, comprising:

[0007] A transconductance amplification module, the transconductance amplification module comprising an input control terminal pair, the input control terminal pair being connected to an input signal pair; the transconductance amplification module being configured to convert the input signal pair into an output current pair and output the output current pair;

[0008] a feedforward transconductance module, the feedforward transconductance module comprising a first feedforward control terminal pair, the first feedforward control terminal pair being connected to the input signal pair and outputting a feedforward current pair, the feedforward current pair comprising a positive-phase feedforward current and a negative-phase feedforward current;

[0009] A gain control module, the gain control module comprising a first differential pair and a second differential pair, the input end of the first differential pair and the input end of the second differential pair serving as a pair of feedforward current input ends of the gain control module; the input end of the first differential pair being connected to the positive-phase feedforward current, the first output end of the first differential pair outputting a first positive-phase compensation current configured to compensate for the positive-phase output current in the output current pair, the second output end of the first differential pair outputting a second positive-phase compensation current configured to compensate for the negative-phase output current in the output current pair; the input end of the second differential pair being connected to the negative-phase feedforward current, the first output end of the second differential pair outputting a first negative-phase compensation current configured to compensate for the positive-phase output current in the output current pair, the second output end of the second differential pair outputting a second negative-phase compensation current configured to compensate for the negative-phase output current in the output current pair.

[0010] According to another aspect of the present application, an oscilloscope is provided, comprising: a front-end module, a sampling module, an input module, a control processing module, a display module and a storage module, wherein the front-end module comprises an attenuation unit and an amplifier as provided in any embodiment of the present application; wherein the input end of the amplifier is connected to the attenuation unit.

[0011] According to another aspect of the present application, an oscilloscope probe is provided, comprising: a probe input terminal, a probe input resistor, a probe input capacitor, an amplifier such as provided in any embodiment of the present application, and a probe output terminal; the input terminal of the amplifier is respectively connected to the probe input resistor and the probe input capacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG1 is a schematic diagram of the structure of an amplifier provided in an embodiment of the present application;

[0013] FIG2 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0014] FIG3 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0015] FIG4 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0016] FIG5 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0017] FIG6 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0018] FIG7 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0019] FIG8 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0020] FIG9 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0021] FIG10 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0022] FIG11 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0023] FIG12 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0024] FIG13 is a circuit diagram of another amplifier provided in an embodiment of the present application;

[0025] FIG14 is a schematic diagram of the structure of an oscilloscope provided in an embodiment of the present application;

[0026] FIG15 is a schematic structural diagram of another oscilloscope provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] FIG1 is a schematic structural diagram of an amplifier provided in an embodiment of the present application. Referring to FIG1 , the amplifier includes: a transconductance amplification module 100 , a feedforward transconductance module 200 and a gain control module 300 .

[0029] The transconductance amplifier module 100 includes an input control terminal pair (including terminal 101P and terminal 101N) connected to an input signal pair (including a positive-phase input signal VIP and a negative-phase input signal VIN). The transconductance amplifier module 100 is configured to convert the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN) into an output current pair (including a positive-phase output current IOP and a negative-phase output current ION) and output the output current pair.

[0030] The feedforward transconductance module 200 includes a first feedforward control terminal pair (including a terminal 201P and a terminal 201N), which is connected to an input signal pair (including a positive-phase input signal VIP and an inverting input signal VIN). The feedforward transconductance module 200 is configured to generate a feedforward current pair (including a positive-phase feedforward current and a negative-phase feedforward current) based on the input signal pair.

[0031] The gain control module 300 includes a first differential pair 301 and a second differential pair 302. The input end of the first differential pair 301 and the input end of the second differential pair 302 serve as a feedforward current input end pair (including a terminal 301P and a terminal 301N) of the gain control module. The input end of the first differential pair 301 is connected to a positive-phase feedforward current. The first output end 302P of the first differential pair 301 outputs a first positive-phase compensation current, which is configured to compensate for the positive-phase output current in the output current pair. The second output end 303P of the first differential pair 301 outputs a second positive-phase compensation current, which is configured to compensate for the negative-phase output current in the output current pair. The input end of the second differential pair 302 is connected to a negative-phase feedforward current. The first output end 302N of the second differential pair 302 outputs a first negative-phase compensation current, which is configured to compensate for the positive-phase output current in the output current pair. The second output end 303N of the second differential pair 302 outputs a second negative-phase compensation current, which is configured to compensate for the negative-phase output current in the output current pair.

[0032] The feedforward current input terminal pair (including terminals 301P and 301N) is connected to the feedforward current pair generated by the feedforward transconductance module 200. The current outputted by the first output terminal 302P and the second output terminal 303P of the first differential pair 301 is a positive-phase compensation current generated based on the positive-phase input signal VIP. This positive-phase compensation current is used to compensate not only the positive-phase output current IOP but also the negative-phase output current ION. Similarly, the current outputted by the first output terminal 302N and the second output terminal 303N of the second differential pair 302 is a negative-phase compensation current generated based on the negative-phase input signal VIN. This negative-phase compensation current is used to compensate not only the negative-phase output current ION but also the positive-phase output current IOP.

[0033] In other words, the current output by the second output terminal 303P of the first differential pair 301 is a positive-phase compensation current generated based on the positive-phase input signal VIP, and the current output by the first output terminal 302N of the second differential pair 302 is a negative-phase compensation current generated based on the negative-phase input signal VIN. The second output terminal 303P of the first differential pair 301 corresponds to the positive-phase output current IOP, and the first output terminal 302N of the second differential pair 302 corresponds to the negative-phase output current ION. This means that the positive-phase compensation current compensates for the positive-phase output current IOP of the transconductance amplification module 100, while the negative-phase compensation current compensates for the negative-phase output current ION of the transconductance amplification module 100. The compensation currents output by the second output terminal 303P of the first differential pair 301 and the first output terminal 302N of the second differential pair 302 constitute a first compensation current pair, which is superimposed and outputted with the output current pair in a corresponding manner.

[0034] The current output by the first output terminal 302P of the first differential pair 301 is a positive-phase compensation current generated based on the positive-phase input signal VIP, and the current output by the second output terminal 303N of the second differential pair 302 is a negative-phase compensation current generated based on the negative-phase input signal VIN. The first output terminal 302P of the first differential pair 301 corresponds to the negative-phase output current ION, while the second output terminal 303N of the second differential pair 302 corresponds to the positive-phase output current IOP. This means that the positive-phase compensation current compensates for the negative-phase output current ION of the transconductance amplification module 100, while the negative-phase compensation current compensates for the positive-phase output current IOP of the transconductance amplification module 100. The compensation currents output by the first output terminal 302P of the first differential pair 301 and the second output terminal 303N of the second differential pair 302 constitute a second compensation current pair, which is interleaved and superimposed with the output current pair.

[0035] Exemplarily, the working principle of the amplifier is as follows: the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN) is converted into an output current pair (including the positive-phase output current IOP and the negative-phase output current ION) through the transconductance amplification module 100. The feedforward transconductance module 200 generates a feedforward current pair based on the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN). The gain control module 300 generates two groups of compensation current pairs based on the feedforward current pair, one group of compensation current pairs is superimposed on the output end of the amplifier in a corresponding manner, and the other group of compensation current pairs is superimposed on the output end of the amplifier in an interlaced manner, thereby compensating for the frequency response of the original output current. The frequency and gain of the two groups of compensation current pairs are controlled by the gain control module 300, which can pull it down when the frequency response is high and pull it up when the frequency response is low, until it is leveled, according to the frequency response characteristics of different batches of amplifiers.

[0036] To sum up, the technical solution of this embodiment converts the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN) into an output current pair (including the positive-phase output current IOP and the negative-phase output current ION) through the transconductance amplification module 100, and at the same time generates two groups of compensation current pairs according to the input signal pair (including the positive-phase input signal VIP and the negative-phase input signal VIN) through the gain control module 300. The two groups of compensation current pairs are superimposed and output with the output current pair in a corresponding and interleaved manner, which can eliminate the influence of process deviation on the frequency response.

[0037] FIG2 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG2 , a transconductance amplification module 100 includes a first current source unit 101, a zeroth transistor Q0, and a first transistor Q1. The first current source unit 101 includes a first connection point pair, which includes a first connection point 102P and a second connection point 102N. The first current source unit 101 is electrically connected to a first power supply voltage (e.g., ground voltage GND).

[0038] The control terminal of the zeroth transistor Q0 and the control terminal of the first transistor Q1 serve as an input control terminal pair (including terminal 101P and terminal 101N) of the transconductance amplification module 100. The first terminal of the zeroth transistor Q0 is electrically connected to the first connection point 102P of the first current source unit 101, and the first terminal of the first transistor Q1 is electrically connected to the second connection point 102N of the first current source unit 101. The second terminal of the zeroth transistor Q0 and the second terminal of the first transistor Q1 output the output current pair of the transconductance amplification module 100 (including the positive-phase output current IOP and the negative-phase output current ION).

[0039] Exemplarily, the transconductance amplifier module 100 operates as follows: a positive-phase input signal VIP is converted into a positive-phase output current IOP by the zeroth transistor Q0, and an inverting input signal VIN is converted into an inverting output current ION by the first transistor Q1. The gain of the output current pair is controlled by the first current source unit 101.

[0040] FIG3 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG3 , in one embodiment, the first current source unit 101 includes a first current source 1011, wherein a current input terminal of the first current source 1011 is electrically connected to a first connection point 102P and a second connection point 102N of the first current source unit 101, and a current output terminal of the first current source 1011 is electrically connected to a first power supply voltage.

[0041] By controlling the current of the first current source 1011, the transconductance of the transistor in the input transconductance amplifier module 100 is controlled, thereby controlling the gain of the output current. This arrangement is easy to implement, does not increase the circuit area, and is conducive to cost control.

[0042] FIG4 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG4 , in another embodiment, the first current source unit 102 includes: a second current source 1012, a first resistor unit R1, and a second resistor unit R2. The first resistor unit R1 is connected in series between the current input terminal of the second current source 1012 and the first connection point 102P of the first current source unit 101. The second resistor unit R2 is connected in series between the current input terminal of the second current source 1012 and the second connection point 102N of the first current source unit 101. The current output terminal of the second current source 1012 is electrically connected to the first power supply voltage.

[0043] By controlling the current of the second current source 1012, the resistance of the first resistor unit R1, and the resistance of the second resistor unit R2, the equivalent transconductance of the transconductance amplifier module 100 can be controlled, thereby controlling the gain of its output current. Compared to providing only a single current source, this configuration adds a resistor unit to the emitter of the transistor in the transconductance amplifier module 100, so that the gain of the output current is controlled by both the current of the current source and the resistance of the resistor unit, thereby increasing the adjustability of the output current gain.

[0044] FIG5 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG5 , in another embodiment, the first current source unit 103 includes: a third current source 1013, a fourth current source 1014, and a third resistor unit R3. The current input terminal of the third current source 1013 is electrically connected to the first connection point 102P of the first current source unit 101, and the current input terminal of the fourth current source 1014 is electrically connected to the second connection point 102N of the first current source unit 101. A third resistor unit R3 is further connected between the current input terminals of the third current source 1013 and the fourth current source 1014. The current output terminals of the third current source 1013 and the fourth current source 1014 are both electrically connected to a first power supply voltage.

[0045] By controlling the currents of the third current source 1013 and the fourth current source 1014, as well as the resistance of the third resistor unit R3, the equivalent transconductance of the transconductance amplifier module 100 can be controlled, thereby controlling the gain of its output current. Compared to a structure in which a single current source is connected to two resistor units, this configuration eliminates the need to consider resistance matching, facilitating stable adjustment of the output current gain.

[0046] Continuing with Figures 1-5 , gain control module 300 further includes a gain control unit 303. Gain control unit 303 includes a second connection point pair (including connection point 305P and connection point 305N). The second connection point pair (including connection point 305P and connection point 305N) of gain control unit 303 is electrically connected to the control end of first differential pair 301, and the second connection point pair (including connection point 305P and connection point 305N) is electrically connected to the control end of second differential pair 302. The second connection point pair (including connection point 305P and connection point 305N) of gain control unit 303 outputs a second control current pair configured to perform gain control on the output currents of first differential pair 301 and second differential pair 302.

[0047] In this embodiment, the frequency and gain of the output current of the feedforward transconductance module 200 are controlled by configuring the first differential pair 301 , the second differential pair 302 and the gain control unit 303 , which is beneficial to further eliminate process deviations and compensate for frequency response.

[0048] FIG6 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG6 , a first differential pair 301 includes a second transistor Q2 and a third transistor Q3. The first end of the second transistor Q2 is electrically connected to the first end of the third transistor Q3 and serves as an input end (i.e., terminal 301P) of the first differential pair 301. The control end of the second transistor Q2 is electrically connected to the control end of the third transistor Q3 and serves as a control end pair of the first differential pair 301. The second end of the second transistor Q2 serves as a first output end 302P of the first differential pair 301, outputting a first positive-phase compensation current. The second end of the third transistor Q3 serves as a second output end 303P of the first differential pair 301, outputting a second positive-phase compensation current.

[0049] Continuing with FIG6 , the second differential pair 302 includes a fourth transistor Q4 and a fifth transistor Q5; a first end of the fourth transistor Q4 and a first end of the fifth transistor Q5 are electrically connected and serve as an input end (terminal 301N) of the second differential pair 302; a control end of the fourth transistor Q4 and a control end of the fifth transistor Q5 are electrically connected and serve as a pair of control ends of the second differential pair 302; a second end of the fourth transistor Q4 serves as a first output end 302N of the second differential pair 302, outputting a first inverted compensation current; and a second end of the fifth transistor Q5 serves as a second output end 303N of the second differential pair 302, outputting a second inverted compensation current.

[0050] The second output terminal 303P of the first differential pair 301 and the second output terminal 303N of the second differential pair 302 output the second set of compensation current pairs, and the first output terminal 302P of the first differential pair 301 and the first output terminal 302N of the second differential pair 302 output the first set of compensation current pairs.

[0051] Exemplarily, the operating principles of the first differential pair 301 and the second differential pair 302 are as follows: the positive-phase compensation current generates a first positive-phase compensation current after passing through the second transistor Q2, and the positive-phase compensation current generates a second positive-phase compensation current after passing through the third transistor Q3. The negative-phase compensation current generates a first negative-phase compensation current after passing through the fourth transistor Q4, and the negative-phase compensation current generates a second negative-phase compensation current after passing through the fifth transistor Q5. The second positive-phase compensation current and the first negative-phase compensation current constitute a first compensation current pair, while the first positive-phase compensation current and the second negative-phase compensation current constitute a second compensation current pair.

[0052] In this embodiment, by providing a second transistor Q2 and a third transistor Q3 in the first differential pair 301, and providing a fourth transistor Q4 and a fifth transistor Q5 in the second differential pair 302, a first compensation current pair and a second compensation current pair are generated according to the input signal and superimposed on the output current pair, which is beneficial to further eliminate process deviations and compensate for frequency response.

[0053] FIG7 is a circuit diagram of another amplifier provided by an embodiment of the present application. Referring to FIG7 , the feedforward transconductance module 200 includes a sixth transistor Q6, a seventh transistor Q7, and a second current source unit 202. The second current source unit 202 includes a third connection point pair (including a connection point 202P and a connection point 202N).

[0054] The control end of the sixth transistor Q6 and the control end of the seventh transistor Q7 respectively serve as the first feedforward control end pair (including terminal 201P and terminal 201N) of the feedforward transconductance module 200. The first end of the sixth transistor Q6 and the first end of the seventh transistor Q7 are respectively electrically connected to the third connection point pair (including the third connection point 202P and the fourth connection point 202N) of the second current source unit 202. The second end of the sixth transistor Q6 and the second end of the seventh transistor Q7 are respectively electrically connected to the feedforward current input end pair (including terminal 301P and terminal 301N) of the gain control module 300. Exemplarily, the second end of the sixth transistor Q6 is electrically connected to the first end of the second transistor Q2 and the first end of the third transistor Q3; the second end of the seventh transistor Q7 is electrically connected to the first end of the fourth transistor Q4 and the first end of the fifth transistor Q5.

[0055] The third connection point pair (including the connection point 202P and the connection point 202N) of the second current source unit 202 outputs a first control current pair, which is configured to perform frequency control on the output current of the feedforward transconductance module 200 .

[0056] Exemplarily, the working principle of the feedforward transconductance module 200 is: under the control of the second current source unit 202, the positive phase input signal VIP is converted into a positive phase compensation current through the sixth transistor Q6, and the negative phase input signal VIN is converted into a negative phase compensation current through the seventh transistor Q7.

[0057] The positive-phase compensation current generates a first positive-phase compensation current after passing through the second transistor Q2, and generates a second positive-phase compensation current after passing through the third transistor Q3. The negative-phase compensation current generates a first negative-phase compensation current after passing through the fourth transistor Q4, and generates a second negative-phase compensation current after passing through the fifth transistor Q5. The second positive-phase compensation current and the first negative-phase compensation current form a first compensation current pair, while the first positive-phase compensation current and the second negative-phase compensation current form a second compensation current pair.

[0058] Thus, the feedforward transconductance module 200 generates a current related to the frequency of the output current of the feedforward transconductance module 200 through the second current source unit 202, i.e., a first control current pair, thereby controlling the frequency of the output current of the feedforward transconductance module 200. The gain control module 300 generates a current related to the gain of the output current of the feedforward transconductance module 200, i.e., a second control current pair, thereby controlling the gain of the output current of the feedforward transconductance module 200.

[0059] In this embodiment, by setting the sixth transistor Q6, the seventh transistor Q7 and the second current source unit 202 in the feedforward transconductance module 200, a frequency-controllable positive-phase compensation current and a frequency-controllable negative-phase compensation current are generated according to the input signal, and are further superimposed on the output current pair through the gain control module 300, which is conducive to further eliminating process deviations and compensating frequency response.

[0060] FIG8 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG8 , the third connection point pair of the second current source unit 202 includes a third connection point 202P and a fourth connection point 202N. The second current source unit 202 includes:

[0061] The fifth current source 2022 has a current input terminal serving as the third connection point 202P of the second current source unit 202 , and a current output terminal electrically connected to a fifth power supply voltage (eg, the ground voltage GND).

[0062] The sixth current source 2023 has a current input terminal serving as the fourth connection point 202N of the second current source unit 202 , and a current output terminal electrically connected to a sixth power supply voltage (eg, the ground voltage GND).

[0063] The current control subunit 2021 is connected in series between the current input terminal of the fifth current source 2022 and the current input terminal of the sixth current source 2023 .

[0064] By controlling the currents of the fifth current source 2022 and the sixth current source 2023, the transconductance of the sixth transistor Q6 and the seventh transistor Q7 is controlled, thereby controlling the gain of the output current, and the frequency of the output current is controlled by the current control subunit 2021. This arrangement has a simple circuit structure and is easy to implement.

[0065] FIG9 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG9 , in one embodiment, the current control subunit 2021 includes: a fourth resistor unit R4 and a first capacitor unit C1. The first end of the fourth resistor unit R4 serves as the first end of the current control subunit 2021. The second end of the fourth resistor unit R4 is electrically connected to the first end of the first capacitor unit C1. The second end of the first capacitor unit C1 serves as the second end of the current control subunit 2021.

[0066] A frequency-dependent current is generated on the fourth resistor unit R4 and the first capacitor unit C1. Therefore, the frequency and gain of the compensation current are determined by the resistance of the fourth resistor unit R4 and the capacitance of the first capacitor unit C1. This arrangement simplifies the circuit structure and is easy to implement.

[0067] FIG10 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG10 , in another embodiment, the current control subunit 2021 includes a second capacitor unit C2, wherein a first end of the second capacitor unit C2 serves as a first end of the current control subunit 2021, and a second end of the second capacitor unit C2 serves as a second end of the current control subunit 2021.

[0068] A frequency-dependent current is generated across the second capacitor unit C2. The frequency and gain of the compensation current are determined by the capacitance of the second capacitor unit C2. This arrangement is suitable for circuits that compensate for high-frequency currents. Compared to a series resistor and capacitor arrangement, it saves circuit area and helps reduce costs.

[0069] FIG11 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG11 , in another embodiment, the current control subunit 2021 includes a fifth resistor unit R5 , wherein a first end of the fifth resistor unit R5 serves as a first end of the current control subunit 2021 , and a second end of the fifth resistor unit R5 serves as a second end of the current control subunit 2021 .

[0070] A frequency-dependent current is generated in the fifth resistor unit R5, and the gain of the compensation current is determined by the resistance value of the fifth resistor unit R5. This configuration ensures that the compensation current has a full frequency range, meaning that it can compensate for both DC signals and AC signals of varying frequencies, further facilitating the elimination of process variations and compensating for frequency response.

[0071] FIG12 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG12 , the gain control unit 303 further includes a first adjustable current source I0, a second adjustable current source I1, an eighth transistor Q8, and a ninth transistor Q9.

[0072] The first end of the eighth transistor Q8 and the first end of the ninth transistor Q9 are electrically connected to the current input end of the first adjustable current source I0 and the current input end of the second adjustable current source I1, respectively. The control end of the eighth transistor Q8, the control end of the ninth transistor Q9, the second end of the eighth transistor Q8, and the second end of the ninth transistor Q9 are electrically connected to the second power supply voltage Vb.

[0073] The current input terminal of the first adjustable current source I0 and the current input terminal of the second adjustable current source I1 serve as a second connection point pair (including connection point 305P and connection point 305N) of the gain control unit 303. The current output terminal of the first adjustable current source I0 is electrically connected to a third power supply voltage (e.g., ground voltage GND). The current output terminal of the second adjustable current source I1 is electrically connected to a fourth power supply voltage (e.g., ground voltage GND).

[0074] For example, taking the transistor as a triode, the control terminal of the transistor is the base of the triode, the first terminal of the transistor is the emitter of the triode, and the second terminal of the transistor is the collector of the triode. The operating principle of the gain control unit 303 is to control the current gain output by the first differential pair and the second differential pair by controlling the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4, and the fifth transistor Q5. When the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4, and the fifth transistor Q5 are equal, the first positive-phase compensation current output by the second transistor Q2 flows to the negative-phase output terminal, the second positive-phase compensation current output by the third transistor Q3 flows to the positive-phase output terminal, the first negative-phase compensation current output by the fourth transistor Q4 flows to the negative-phase output terminal, and the second negative-phase compensation current output by the fifth transistor Q5 flows to the positive-phase output terminal. At this time, the compensation currents flowing to the positive-phase output terminal and the negative-phase output terminal cancel each other out, and do not affect the output current gain.

[0075] When the gain control unit 303 is adjusted to increase the current of the first adjustable current source I0 and decrease the current of the second adjustable current source I1, the emitter voltage of the eighth transistor Q8 decreases and the emitter voltage of the ninth transistor Q9 increases. This controls the base voltage of the third transistor Q3 and the fourth transistor Q4 to increase, increases the second positive-phase compensation current flowing to the in-phase output terminal, and increases the first negative-phase compensation current flowing to the negative-phase output terminal. The base voltage of the second transistor Q2 and the fifth transistor Q5 decreases, decreases the second negative-phase compensation current flowing to the in-phase output terminal, and decreases the first positive-phase compensation current flowing to the negative-phase output terminal. Ultimately, the effective current flowing to the in-phase output terminal and the negative-phase output terminal increases, and the overall current gain increases. For example, when the frequency response of the frequency point is low, it is necessary to increase the gain of the compensation current to compensate for the frequency response.

[0076] When the gain control unit 303 is adjusted to reduce the current of the first adjustable current source I0 and increase the current of the second adjustable current source I1, the emitter voltage of the eighth transistor Q8 increases, and the emitter voltage of the ninth transistor Q9 decreases. This controls the base voltages of the third transistor Q3 and the fourth transistor Q4 to decrease, reducing the second positive-phase compensation current flowing to the in-phase output terminal and the first negative-phase compensation current flowing to the negative-phase output terminal. The base voltages of the second transistor Q2 and the fifth transistor Q5 increase, increasing the second negative-phase compensation current flowing to the in-phase output terminal and the first positive-phase compensation current flowing to the negative-phase output terminal. Ultimately, the effective current flowing to the in-phase output terminal and the negative-phase output terminal decreases, and the overall current gain decreases. For example, when the frequency response of the frequency point is high, it is necessary to reduce the gain of the compensation current to compensate for the frequency response.

[0077] It should be noted that there are multiple ways to set up the gain control unit 303. Its purpose is to control the base voltages of the second transistor Q2, the third transistor Q3, the fourth transistor Q4 and the fifth transistor Q5 in the interleaving compensation unit 301. The higher the control voltage, the easier it is for the transistor to turn on.

[0078] In this embodiment, by providing a first adjustable current source I0, a second adjustable current source I1, an eighth transistor Q8, and a ninth transistor Q9 in the gain control unit 303, the base voltages of the transistors in the interleaving compensation unit 301 connected thereto can be controlled, thereby controlling the gain of the output current of the interleaving compensation unit 301 and achieving a compensated frequency response. This arrangement simplifies the circuit structure, is easy to implement, and facilitates precise adjustment of the current gain.

[0079] FIG13 is a circuit diagram of another amplifier provided in an embodiment of the present application. Referring to FIG13 , the amplifier further includes:

[0080] The first current buffer module 400 is connected in series between the transconductance amplification module 100 and the output terminal of the amplifier. The first current buffer module 400 includes a first buffer control terminal pair (including a terminal 401P and a terminal 401N), which is connected to a reference voltage V1.

[0081] Continuing with FIG. 13 , the first current buffer module 400 includes a tenth transistor Q10 and an eleventh transistor Q11. The control terminals of the tenth transistor Q10 and the eleventh transistor Q11 are connected to a reference voltage V1. The first terminals of the tenth transistor Q10 and the eleventh transistor Q11 are connected to the output current pair of the transconductance amplification module 100. The second terminals of the tenth transistor Q10 and the eleventh transistor Q11 output a first buffer current pair (comprising a terminal 402P and a terminal 402N).

[0082] The first buffer current pair includes a positive-phase buffer current and a negative-phase buffer current. The positive-phase output current of the transconductance amplification module 100 is converted into a positive-phase buffer current by the tenth transistor Q10 and flows to the non-inverting output terminal. The negative-phase output current of the transconductance amplification module 100 is converted into a negative-phase buffer current by the eleventh transistor Q11 and flows to the negative-phase output terminal.

[0083] In this embodiment, by providing the first current buffer module 400 , the output current of the transconductance amplification module 100 is buffered by using the transistors provided therein, thereby improving the safety of the circuit.

[0084] It should be noted that, in the above-mentioned multiple embodiments, the transistor is described as a triode, which is not a limitation of the present application. In other embodiments, the transistor can also be set as a MOS tube, etc.

[0085] The embodiment of the present application further provides an oscilloscope, which includes the amplifier provided by any of the above embodiments. The oscilloscope provided by this embodiment has the beneficial effects of the amplifier provided by any of the above embodiments, which will not be described in detail here.

[0086] Figure 14 is a schematic diagram of the structure of an oscilloscope provided in an embodiment of the present application. Referring to Figure 14 , the oscilloscope includes a front-end module 1, a sampling module 2, an input module 3, a control and processing module 4, a display module 5, and a storage module 6. The front-end module 1 includes an attenuation unit 11 and an amplifier 12. The input of the amplifier 12 is connected to the attenuation unit 11.

[0087] The embodiment of the present application further provides an oscilloscope probe, which includes the amplifier provided by any of the above embodiments. The oscilloscope probe provided by this embodiment has the beneficial effects of the amplifier provided by any of the above embodiments, which will not be described in detail here.

[0088] FIG15 is a schematic diagram of the structure of another oscilloscope provided in an embodiment of the present application. Referring to FIG15 , the oscilloscope includes an oscilloscope probe 7 and an oscilloscope input resistor R in .

[0089] 15 , the oscilloscope probe 7 includes a probe input terminal 72 and a probe input resistor R probe , probe input capacitance C probe , amplifier 71 and probe output terminal 73. Among them, the input terminal of amplifier 71 is respectively connected to the probe input resistor R probe and the probe input capacitance C probe Connect the probe output terminal 73 to the oscilloscope input resistor R in connect.

[0090] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the multiple steps described in this application can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of this application can be achieved. This is not limited herein.

Claims

1. An amplifier, comprising: A transconductance amplification module, the transconductance amplification module comprising an input control terminal pair, the input control terminal pair being connected to an input signal pair; the transconductance amplification module being configured to convert the input signal pair into an output current pair and output the output current pair; a feedforward transconductance module, the feedforward transconductance module comprising a first feedforward control terminal pair, the first feedforward control terminal pair being connected to the input signal pair and outputting a feedforward current pair, the feedforward current pair comprising a positive-phase feedforward current and a negative-phase feedforward current; A gain control module, the gain control module comprising a first differential pair and a second differential pair, the input end of the first differential pair and the input end of the second differential pair serving as a pair of feedforward current input ends of the gain control module; the input end of the first differential pair being connected to the positive-phase feedforward current, the first output end of the first differential pair outputting a first positive-phase compensation current configured to compensate for the positive-phase output current in the output current pair, the second output end of the first differential pair outputting a second positive-phase compensation current configured to compensate for the negative-phase output current in the output current pair; the input end of the second differential pair being connected to the negative-phase feedforward current, the first output end of the second differential pair outputting a first negative-phase compensation current configured to compensate for the positive-phase output current in the output current pair, the second output end of the second differential pair outputting a second negative-phase compensation current configured to compensate for the negative-phase output current in the output current pair.

2. The amplifier according to claim 1, wherein The transconductance amplification module includes a first current source unit, a zeroth transistor and a first transistor; the first current source unit includes a first connection point pair, the first connection point pair includes a first connection point and a second connection point; the first current source unit is electrically connected to a first power supply voltage; The control end of the zeroth transistor and the control end of the first transistor serve as an input control end pair of the transconductance amplification module; the first end of the zeroth transistor is electrically connected to the first connection point of the first current source unit, and the first end of the first transistor is electrically connected to the second connection point of the first current source unit; the second end of the zeroth transistor and the second end of the first transistor output the output current pair of the transconductance amplification module.

3. The amplifier according to claim 2, wherein Meet one of the following: The first current source unit includes: a first current source, a current input terminal of the first current source is electrically connected to a first connection point and a second connection point of the first current source unit, and a current output terminal of the first current source is electrically connected to a first power supply voltage; The first current source unit includes: a second current source, a first resistance unit, and a second resistance unit, the first resistance unit is connected in series between a current input terminal of the second current source and a first connection point of the first current source unit, the second resistance unit is connected in series between a current input terminal of the second current source and a second connection point of the first current source unit, and a current output terminal of the second current source is electrically connected to a first power supply voltage; and The first current source unit includes: a third current source, a fourth current source and a third resistance unit, the current input end of the third current source is electrically connected to the first connection point of the first current source unit, and the current input end of the fourth current source is electrically connected to the second connection point of the first current source unit; the third 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, and the current output end of the third current source and the current output end of the fourth current source are respectively electrically connected to the first power supply voltage.

4. The amplifier according to claim 1, wherein The gain control module further includes: A gain control unit, the gain control unit including a second connection point pair, the second connection point pair of the gain control unit being electrically connected to the control end pair of the first differential pair, and the second connection point pair of the gain control unit being electrically connected to the control end pair of the second differential pair; the second connection point pair of the gain control unit outputting a second control current pair, configured to perform gain control on the output currents of the first differential pair and the second differential pair.

5. The amplifier according to claim 4, wherein The first differential pair includes a second transistor and a third transistor; The first end of the second transistor and the first end of the third transistor are electrically connected and serve as input ends of the first differential pair; The control end of the second transistor and the control end of the third transistor are electrically connected and serve as a control end pair of the first differential pair; The second end of the second transistor serves as the first output end of the first differential pair, outputting the first positive phase compensation current; the second end of the third transistor serves as the second output end of the first differential pair, outputting the second positive phase compensation current; And / or, the second differential pair includes a fourth transistor and a fifth transistor; The first end of the fourth transistor is electrically connected to the first end of the fifth transistor and serves as an input end of the second differential pair; The control end of the fourth transistor and the control end of the fifth transistor are electrically connected and serve as a control end pair of the second differential pair; The second end of the fourth transistor serves as the first output end of the second differential pair, outputting the first inverted compensation current; the second end of the fifth transistor serves as the second output end of the second differential pair, outputting the second inverted compensation current.

6. The amplifier according to claim 1, wherein The feedforward transconductance module includes: a sixth transistor, a seventh transistor and a second current source unit; the second current source unit includes a third connection point pair; The control end of the sixth transistor and the control end of the seventh transistor serve as a first feedforward control end pair of the feedforward transconductance module; the first end of the sixth transistor and the first end of the seventh transistor are electrically connected to the third connection end pair of the second current source unit respectively; the second end of the sixth transistor and the second end of the seventh transistor are electrically connected to the feedforward current input end pair of the gain control module respectively; The third connection point of the second current source unit outputs a first control current pair, which is set to output the feedforward transconductance module. The current is frequency controlled.

7. The amplifier according to claim 6, wherein The third connection point pair of the second current source unit includes a third connection point and a fourth connection point; the second current source unit includes: a fifth current source, wherein a current input terminal of the fifth current source serves as a third connection point of the second current source unit, and a current output terminal of the fifth current source is electrically connected to a fifth power supply voltage; a sixth current source, wherein a current input terminal of the sixth current source serves as a fourth connection point of the second current source unit, and a current output terminal of the sixth current source is electrically connected to a sixth power supply voltage; A current control subunit is connected in series between the current input terminal of the fifth current source and the current input terminal of the sixth current source.

8. The amplifier according to claim 7, wherein Meet one of the following: The current control subunit includes: a fourth resistor unit and a first capacitor unit, the first end of the fourth resistor unit serves as the first end of the current control subunit, the second end of the fourth resistor unit is electrically connected to the first end of the first capacitor unit, and the second end of the first capacitor unit serves as the second end of the current control subunit; The current control subunit includes: a second capacitor unit, a first end of the second capacitor unit serving as the first end of the current control subunit, and a second end of the second capacitor unit serving as the second end of the current control subunit; and The current control subunit includes: a fifth resistance unit, a first end of the fifth resistance unit serving as the first end of the current control subunit, and a second end of the fifth resistance unit serving as the second end of the current control subunit.

9. The amplifier according to claim 4, wherein The gain control unit includes a first adjustable current source, a second adjustable current source, an eighth transistor and a ninth transistor; a first end of the eighth transistor and a first end of the ninth transistor are electrically connected to the current input end of the first adjustable current source and the current input end of the second adjustable current source, respectively; a control end of the eighth transistor, a control end of the ninth transistor, a second end of the eighth transistor, and a second end of the ninth transistor are electrically connected to a second power supply voltage; The current input end of the first adjustable current source and the current input end of the second adjustable current source serve as a second connection point pair of the gain control unit; the current output end of the first adjustable current source is electrically connected to a third power supply voltage; and the current output end of the second adjustable current source is electrically connected to a fourth power supply voltage.

10. The amplifier of claim 1 , further comprising: a first current buffer module, the first current buffer module being connected in series between the transconductance amplification module and the output end of the amplifier; The first current buffer module includes a first buffer control terminal pair, and the first buffer control terminal pair is connected to a reference voltage.

11. An oscilloscope comprising: A front-end module, a sampling module, an input module, a control processing module, a display module and a storage module, wherein the front-end module includes an attenuation unit and an amplifier according to any one of claims 1 to 10; wherein the input end of the amplifier is connected to the attenuation unit.

12. An oscilloscope probe, comprising: A probe input terminal, a probe input resistor, a probe input capacitor, an amplifier according to any one of claims 1 to 10, and a probe output terminal; the input terminal of the amplifier is connected to the probe input resistor and the probe input capacitor respectively.

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