Signal amplification circuit

Abstract

The utility model provides a signal amplification circuit. The circuit comprises a variable resistor assembly, a signal feedback circuit and a variable gain amplification circuit, the first end of the variable resistor assembly is the input end of the signal amplification circuit, and the second end of the variable resistor assembly is connected with the input end of the signal feedback circuit; the output end of the signal feedback circuit is connected with the third end of the variable resistor assembly. The second end of the variable resistor assembly is further connected with the input end of the variable gain amplification circuit, and the output end of the variable gain amplification circuit is the output end of the signal amplification circuit. According to the circuit, the problems of unadaptive gain, insufficient linearity and poor noise performance in the prior art are solved, and the reliability of an amplified signal is improved.

Description

Technical Field

[0001] This utility model relates to the field of amplifier circuit technology, and more specifically, to a signal amplifier circuit. Background Technology

[0002] Traditional amplifier circuits typically have a fixed gain setting. If the amplitude of the input signal varies significantly, a fixed gain may lead to over-amplification of small signals (causing noise amplification) or clipping of large signals (saturation distortion). Fixed-gain amplifiers may also amplify noise when processing very weak signals, resulting in a decrease in the signal-to-noise ratio (SNR). This noise problem can be particularly pronounced in low-frequency or high-sensitivity applications. Utility Model Content

[0003] The purpose of this utility model embodiment is to provide a signal amplification circuit that solves the problems of unsuitable gain, insufficient linearity, and poor noise performance in the prior art, thereby improving the reliability of the amplified signal.

[0004] In a first aspect, a signal amplification circuit is provided, which may include: a variable resistor component, a signal feedback circuit, and a variable gain amplification circuit;

[0005] The first end of the variable resistor component is the input end of the signal amplification circuit, and the second end of the variable resistor component is connected to the input end of the signal feedback circuit.

[0006] The output terminal of the signal feedback circuit is connected to the third terminal of the variable resistor component;

[0007] The second end of the variable resistor component is also connected to the input end of the variable gain amplifier circuit, and the output end of the variable gain amplifier circuit is the output end of the signal amplifier circuit.

[0008] In one possible implementation, the variable resistor assembly includes a single-pole double-throw relay, a first resistor, and a second resistor;

[0009] The normally open terminal of the single-pole double-throw relay is connected to one end of the first resistor, and the other end of the first resistor is connected to the output section of the variable resistor assembly. The normally closed terminal of the single-pole double-throw relay is connected to one end of the second resistor, and the other end of the second resistor is connected to the output section of the variable resistor assembly.

[0010] The common terminal of the single-pole double-throw relay is the third terminal of the variable resistor component.

[0011] In one possible implementation, the signal feedback circuit includes a signal peak detector and a comparator;

[0012] The input terminal of the signal peak detector is the input terminal of the signal feedback circuit;

[0013] The output terminal of the signal peak detector is connected to the first input terminal of the comparator, and the second input terminal of the comparator is connected to the reference voltage;

[0014] The output of the comparator is the output of the signal feedback circuit.

[0015] In one possible implementation, the reference voltage is 2.5V.

[0016] In one possible implementation, the signal peak detector is a signal strength detector.

[0017] In one possible implementation, the variable gain amplifier circuit includes three resistors, one capacitor, and one operational amplifier;

[0018] Of the three resistors, one end of the first resistor is the input terminal of the variable gain amplifier circuit, and the other end of the first resistor is connected to the first input terminal of the operational amplifier.

[0019] The second input terminal of the operational amplifier is connected to one end of the second resistor among the three resistors, and the other end of the second resistor is grounded; the positive plate of the capacitor is connected to one end of the second resistor, and the negative plate of the capacitor is connected to the other end of the second resistor.

[0020] Of the three resistors, one end of the third resistor is connected to one end of the second resistor, and the other end of the third resistor is connected to the output terminal of the operational amplifier;

[0021] The output terminal of the operational amplifier is the output terminal of the variable gain amplifier circuit.

[0022] In some embodiments, the variable gain amplifier circuit can be a voltage-controlled gain amplifier.

[0023] The signal amplification circuit provided by this utility model includes: a variable resistor component, a signal feedback circuit, and a variable gain amplifier circuit; the first terminal of the variable resistor component is the input terminal of the signal amplification circuit, and the second terminal of the variable resistor component is connected to the input terminal of the signal feedback circuit; the output terminal of the signal feedback circuit is connected to the third terminal of the variable resistor component; the second terminal of the variable resistor component is also connected to the input terminal of the variable gain amplifier circuit, and the output terminal of the variable gain amplifier circuit is the output terminal of the signal amplification circuit. This circuit improves the reliability of the amplified signal. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments of this utility model will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of a signal amplification circuit provided in an embodiment of this utility model;

[0026] Figure 2 A schematic diagram of the structure of a variable resistor assembly provided in an embodiment of this utility model;

[0027] Figure 3 A schematic diagram of a signal feedback circuit provided in an embodiment of this utility model;

[0028] Figure 4 This is a schematic diagram of a variable gain amplifier circuit provided for an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model. Unless otherwise defined, the technical or scientific terms used in the present utility model should have the ordinary meaning understood by those skilled in the art to which the present utility model pertains. The words "first," "second," and similar terms used in the present utility model do not indicate any order, quantity, or importance, but are only used to distinguish different components. The words "comprising" or "including," etc., mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects. The words "connection," "coupled," or "linked," etc., are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up," "down," "left," and "right" are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0030] Figure 1 This is a schematic diagram of a signal amplification circuit provided by this utility model, as shown below. Figure 1As shown, the circuit may include: a variable resistor component 100, a signal feedback circuit 200, and a variable gain amplifier circuit 300;

[0031] The first end of the variable resistor component 100 is the input terminal of the signal amplification circuit; the second end of the variable resistor component 100 is connected to the input terminal of the signal feedback circuit 200; the output terminal of the signal feedback circuit 200 is connected to the third end of the variable resistor component 100; the second end of the variable resistor component 100 is also connected to the input terminal of the variable gain amplifier circuit 300, and the output terminal of the variable gain amplifier circuit 300 is the output terminal of the signal amplification circuit.

[0032] The signal feedback circuit 200 is used to receive the signal output by the variable resistor component 100, detect its peak value, compare it with the reference voltage Vref, output a comparison signal, and send the comparison signal to the variable resistor component 100.

[0033] The variable resistor component 100 is used to receive the signal to be amplified from the initial input signal amplification circuit; and to receive the comparison signal output from the signal feedback circuit 200, so as to change the resistance value connected to the signal amplification circuit and output the processed signal.

[0034] The variable gain amplifier circuit 300 is used to amplify the processed signal output from the variable resistor component 100 to obtain an amplified signal.

[0035] like Figure 2 As shown, the variable resistor assembly 100 may include a single-pole double-throw relay 110, a first resistor R1 120, and a second resistor R2 130;

[0036] The normally open terminal of the single-pole double-throw relay 110 is connected to one end of the first resistor R1 120, and the other end of the first resistor R1 120 is connected to the output section of the variable resistor assembly 100. The normally closed terminal of the single-pole double-throw relay 110 is connected to one end of the second resistor R2 130, and the other end of the second resistor R2 130 is connected to the output section of the variable resistor assembly 100.

[0037] The common terminal of the single-pole double-throw relay 110 is the third terminal of the variable resistor component 100.

[0038] like Figure 3 As shown, the signal feedback circuit 200 may include a signal peak detector 210 and a comparator 220;

[0039] The input terminal of the signal peak detector 210 is the input terminal of the signal feedback circuit 200;

[0040] The output of the signal peak detector 210 is connected to the first input of the comparator 220, and the second input of the comparator 220 is connected to the reference voltage Vref, which can be 2.5V.

[0041] The output of comparator 220 is the output of signal feedback circuit 200.

[0042] In some embodiments, the signal peak detector may be a signal strength detector.

[0043] like Figure 4 As shown, the variable gain amplifier circuit 300 may include three resistors (i.e., R1 310, R2 320 and R3330), a capacitor C 340 and an operational amplifier 350;

[0044] Of the three resistors, one end of the first resistor R1 310 is the input terminal of the variable gain amplifier circuit 300, and the other end of the first resistor R1 310 is connected to the first input terminal of the operational amplifier 350.

[0045] The second input terminal of the operational amplifier 350 is connected to one end of the second resistor R2 320 of the three resistors, and the other end of the second resistor R2 320 is grounded;

[0046] The positive plate of capacitor C340 is connected to one end of the second resistor, and the negative plate of capacitor C340 is connected to the other end of the second resistor R2320.

[0047] One end of the third resistor R3 330 is connected to one end of the second resistor R2 320, and the other end of the third resistor R3 330 is connected to the output of the operational amplifier 350.

[0048] The output of operational amplifier 350 is the output of variable gain amplifier circuit 300.

[0049] The parameters are R1 and R2 are 10kΩ, R3 is 100kΩ, C is 6pF, and the operational amplifier can be AD8652 or ADA4530.

[0050] In some embodiments, the variable gain amplifier circuit can be a voltage-controlled gain amplifier, that is, an amplifier circuit that utilizes the gate voltage of the field-effect transistor to construct a logarithmic relationship with the resistance between the drain and the source. This circuit structure is an existing structure and will not be described in detail here.

[0051] This utility model provides a signal amplification circuit, comprising: a variable resistor component, a signal feedback circuit, and a variable gain amplifier circuit; the first terminal of the variable resistor component is the input terminal of the signal amplification circuit, and the second terminal of the variable resistor component is connected to the input terminal of the signal feedback circuit; the output terminal of the signal feedback circuit is connected to the third terminal of the variable resistor component; the second terminal of the variable resistor component is also connected to the input terminal of the variable gain amplifier circuit, and the output terminal of the variable gain amplifier circuit is the output terminal of the signal amplification circuit. This circuit solves the problems of gain mismatch, insufficient linearity, and poor noise performance in the prior art, and improves the reliability of the amplified signal.

[0052] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0053] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this utility model without departing from the spirit and scope of the embodiments of this utility model. Therefore, if these modifications and variations to the embodiments of this utility model fall within the scope of the claims in this utility model and their equivalents, then this utility model also intends to include these modifications and variations.

Claims

1. A signal amplification circuit, characterized in that, The circuit includes: a variable resistor assembly, a signal feedback circuit, and a variable gain amplifier circuit; The first end of the variable resistor component is the input end of the signal amplification circuit, and the second end of the variable resistor component is connected to the input end of the signal feedback circuit. The output terminal of the signal feedback circuit is connected to the third terminal of the variable resistor component; The second end of the variable resistor component is also connected to the input end of the variable gain amplifier circuit, and the output end of the variable gain amplifier circuit is the output end of the signal amplifier circuit.

2. The circuit as described in claim 1, characterized in that, The variable resistor assembly includes a single-pole double-throw relay, a first resistor, and a second resistor; The normally open terminal of the single-pole double-throw relay is connected to one end of the first resistor, and the other end of the first resistor is connected to the output section of the variable resistor assembly. The normally closed terminal of the single-pole double-throw relay is connected to one end of the second resistor, and the other end of the second resistor is connected to the output section of the variable resistor assembly. The common terminal of the single-pole double-throw relay is the third terminal of the variable resistor component.

3. The circuit as described in claim 1, characterized in that, The signal feedback circuit includes a signal peak detector and a comparator; The input terminal of the signal peak detector is the input terminal of the signal feedback circuit; The output terminal of the signal peak detector is connected to the first input terminal of the comparator, and the second input terminal of the comparator is connected to the reference voltage; The output of the comparator is the output of the signal feedback circuit.

4. The circuit as described in claim 3, characterized in that, The reference voltage is 2.5V.

5. The circuit as described in claim 3, characterized in that, The signal peak detector is a signal strength detector.

6. The circuit as described in claim 1, characterized in that, The variable gain amplifier circuit includes three resistors, one capacitor, and one operational amplifier; Of the three resistors, one end of the first resistor is the input terminal of the variable gain amplifier circuit, and the other end of the first resistor is connected to the first input terminal of the operational amplifier. The second input terminal of the operational amplifier is connected to one end of the second resistor among the three resistors, and the other end of the second resistor is grounded; the positive plate of the capacitor is connected to one end of the second resistor, and the negative plate of the capacitor is connected to the other end of the second resistor. Of the three resistors, one end of the third resistor is connected to one end of the second resistor, and the other end of the third resistor is connected to the output terminal of the operational amplifier; The output terminal of the operational amplifier is the output terminal of the variable gain amplifier circuit.

7. The circuit as described in claim 1, characterized in that, The variable gain amplifier circuit is a voltage-controlled gain amplifier.

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