Signal amplification circuit

Abstract

The utility model discloses a signal amplification circuit. The signal amplification circuit comprises a signal input end, a signal amplification stage, a variable-voltage potentiometer and a signal output end; the signal input end receives an input signal, and the input end of the signal amplification stage is connected with the signal input end; the output end of the signal amplification stage is connected with the input end of the voltage transformation type potentiometer, and the output end of the voltage transformation type potentiometer is connected with the signal output end. According to the signal amplification circuit, the voltage transformation type potentiometer is arranged behind the output stage, so that the signal amplification circuit outputs low impedance, and impedance matching between the signal amplification circuit and a subsequent circuit is facilitated.

Description

Technical Field

[0001] The utility model relates to the field of audio, in particular to a signal amplifying circuit. Background Art

[0002] Audio refers specifically to an audio system that produces sound through a combination of electrical equipment. In the audio system, there is a signal amplification circuit. In the existing signal amplification circuit, the amplifier and potentiometer are both set before the signal amplification stage.

[0003] However, the output impedance of the output stage of the existing signal amplifier circuit is high, which is not conducive to matching and connecting subsequent circuits. Utility Model Content

[0004] The utility model aims to overcome the deficiencies in the prior art and provide a signal amplifying circuit, in which a transformer-type potentiometer is arranged after the output stage, so that the signal amplifying circuit outputs low impedance, and the signal amplifying circuit is conveniently matched with the impedance of subsequent circuits.

[0005] The purpose of this utility model is achieved through the following technical solutions:

[0006] The signal amplification circuit comprises: a signal input terminal, a signal amplification stage, a transformer type potentiometer and a signal output terminal; the signal input terminal receives an input signal, the input terminal of the signal amplification stage is connected to the signal input terminal; the output terminal of the signal amplification stage is connected to the input terminal of the transformer type potentiometer, and the output terminal of the transformer type potentiometer is connected to the signal output terminal.

[0007] Preferably, the transformer potentiometer is a multi-tap transformer potentiometer.

[0008] Preferably, the signal amplifying circuit further comprises a control circuit module, and the control circuit module is connected to the control end of the transformer potentiometer.

[0009] Preferably, the control circuit module includes a control unit and a relay control unit; the control unit receives a control signal, and the output end of the control unit is connected to the input end of the relay control unit; the output end of the relay control unit is connected to the control end of the transformer potentiometer.

[0010] Preferably, the control unit is a single chip microcomputer.

[0011] Preferably, the control circuit module further comprises a power supply unit, an input end of the power supply unit is externally connected to a power supply; and an output end of the power supply unit is connected to a power input end of the control unit.

[0012] Preferably, the control circuit module further comprises a current amplifying driving unit, the input end of the current amplifying driving unit is connected to the output end of the control unit, and the output end of the current amplifying driving unit is connected to the relay control unit.

[0013] Compared with the prior art, the utility model has at least the following advantages:

[0014] The signal amplifier circuit is provided with a transformer potentiometer after the output stage, so that the signal amplifier circuit outputs low impedance, making it convenient for the signal amplifier circuit to match the impedance of subsequent circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 This is a schematic diagram of a signal amplifying circuit according to Embodiment 1 of the present utility model;

[0017] Figure 2 This is a schematic diagram of a signal amplifying circuit according to Embodiment 2 of the present utility model. DETAILED DESCRIPTION

[0018] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the accompanying drawings. The accompanying drawings show preferred embodiments of the present invention. Example 1

[0019] like Figure 1 As shown, the utility model discloses a signal amplifying circuit 10, comprising: a signal input terminal 11, a signal amplifying stage 12, a transformer type potentiometer and a signal output terminal 13. The signal input terminal 11 receives an input signal, and the input terminal of the signal amplifying stage 12 is connected to the signal input terminal 11. The output terminal of the signal amplifying stage 12 is connected to the input terminal of the transformer type potentiometer, and the output terminal of the transformer type potentiometer is connected to the signal output terminal 13.

[0020] like Figure 1 As shown, in this embodiment, the transformer potentiometer is a multi-tap transformer potentiometer 14.

[0021] The audio signal is input from the signal input terminal 11 to the signal amplifier stage 12, and is output to the signal input terminal of the multi-tap transformer potentiometer 14 after being amplified by the signal amplifier stage 12; the audio signal is adjusted by the multi-tap transformer potentiometer 14 and the corresponding audio signal is output to the signal output terminal 13.

[0022] The signal amplifier circuit 10 of the present invention arranges a multi-tap transformer potentiometer 14 at the rear end of the signal amplifier stage 12 (i.e., the multi-tap transformer potentiometer 14 is arranged at the output stage of the signal amplifier circuit 10), and utilizes the characteristics of the multi-tap transformer potentiometer 12 with high input impedance and low output impedance, so that the signal amplifier circuit 10 is easy to match the circuit connected later. Example 2

[0023] like Figure 2 As shown, the utility model discloses a signal amplifying circuit 20, comprising: a signal input terminal 21, a signal amplifying stage 22, a transformer type potentiometer 24, a signal output terminal 23 and a control circuit module 25. The signal input terminal 21 receives an input signal, the input terminal of the signal amplifying stage 22 is connected to the signal input terminal 21; the output terminal of the signal amplifying stage 22 is connected to the input terminal of the transformer type potentiometer, the output terminal of the transformer type potentiometer is connected to the signal output terminal 23; the control circuit module 25 is connected to the control terminal of the transformer type potentiometer.

[0024] like Figure 2 As shown, the audio signal is input from the signal input terminal 21 to the signal amplifier stage 22, and is output to the signal input terminal of the multi-tap transformer potentiometer 24 after being amplified by the signal amplifier stage 22; the audio signal is adjusted by the multi-tap transformer potentiometer 24 and the corresponding audio signal is output to the signal output terminal 23.

[0025] The signal amplifying circuit 20 of the present invention arranges a multi-tap transformer potentiometer 24 at the rear end of the signal amplifying stage 22 (i.e., the multi-tap transformer potentiometer 24 is arranged at the output stage of the signal amplifying circuit 22), and utilizes the characteristics of the multi-tap transformer potentiometer 24 with high input impedance and low output impedance, so that the signal amplifying circuit 20 is easy to match the circuit connected later.

[0026] like Figure 2 As shown, in this embodiment, the control circuit module 25 includes a control unit 251, a current amplification drive unit 252, a relay control unit 253 and a power supply unit 254. The input end of the power supply unit 254 is externally connected to a power supply; the output end of the power supply unit 254 is connected to the power input end of the control unit 251. The control unit 251 receives a control signal, and the output end of the control unit 251 is connected to the input end of the current amplification drive unit 252; the output end of the current amplification drive unit 252 is connected to the input end of the relay control unit 253; the output end of the relay control unit 253 is connected to the control end of the multi-tap transformer potentiometer 24. In this embodiment, the control unit 251 is a single-chip microcomputer, and the model of the single-chip microcomputer is not limited. The current amplification drive unit is ULN2003.

[0027] In this embodiment, the input end of the power supply unit 254 is externally connected to a 12V power supply, and the output end of the power supply unit 254 inputs a 5V power supply voltage to the power input end of the control unit 251. The power supply unit 254 provides a stable 5V voltage to the control unit 251 to ensure that the control unit 251 works stably, thereby ensuring the stability of the signal amplification circuit 20. As a preferred embodiment, the power supply unit 254 includes a voltage stabilizer, and the model of the voltage stabilizer is LM78M05. Of course, the voltage stabilizer is not limited to the LM78M05 model voltage stabilizer, and other models of voltage stabilizers can also be used.

[0028] The control unit 251 receives the control signal and outputs the corresponding relay control signal to the current amplification drive unit 252 according to the control signal, and then inputs the current to the relay control unit 253; the relay control unit 253 controls the on and off of the switch relay (K1...Kn) in the multi-tap transformer potentiometer 24 according to the control signal. The control unit 251 receives the control signal through an external interface, wherein the external interface can be Uart, IIC, SPI and other interfaces, but is not limited to these interfaces.

[0029] In this embodiment, the relay control unit 253 includes a plurality of relay control coils (K1A...KnA), and the plurality of relay control coils (K1A...KnA) correspond one-to-one to the switch relays (K1...Kn) in the multi-tap transformer potentiometer 24, respectively.

[0030] When the signal amplifier circuit 20 is working, the external 12V power supply is stabilized by the voltage stabilizer LM78M05 and then outputs a 5V power supply voltage. The 5V power supply voltage is further stabilized and filtered by the voltage stabilizing and filtering unit (composed of a voltage stabilizing capacitor C4 and a filtering capacitor C2 in parallel) and then inputs a stable 5V power supply voltage to the microcontroller IC1.

[0031] The external interface inputs a control signal (serial port signal) from the single-chip microcomputer IC1; the single-chip microcomputer IC1 outputs a corresponding relay control signal to the current amplification drive unit 252 for amplification, and then controls the relay control coil (K1A...KnA) respectively, thereby controlling the on and off of the switch relay (K1...Kn) in the multi-tap transformer potentiometer 24.

[0032] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A signal amplification circuit, characterized in that: include: A signal input terminal, a signal amplifying stage, a transformer type potentiometer and a signal output terminal; the signal input terminal receives an input signal, the input terminal of the signal amplifying stage is connected to the signal input terminal; the output terminal of the signal amplifying stage is connected to the input terminal of the transformer type potentiometer, and the output terminal of the transformer type potentiometer is connected to the signal output terminal.

2. The signal amplifying circuit according to claim 1, characterized in that: The transformer potentiometer is a multi-tap transformer potentiometer.

3. The signal amplifying circuit according to claim 1, characterized in that: It also includes a control circuit module, which is connected to the control end of the transformer potentiometer.

4. The signal amplifying circuit according to claim 3, characterized in that: The control circuit module includes a control unit and a relay control unit; the control unit receives a control signal, and the output end of the control unit is connected to the input end of the relay control unit; the output end of the relay control unit is connected to the control end of the transformer potentiometer.

5. The signal amplifying circuit according to claim 4, characterized in that: The control unit is a single chip microcomputer.

6. The signal amplifying circuit according to claim 4, characterized in that: The control circuit module also includes a power supply unit, an input end of the power supply unit is externally connected to a power supply; and an output end of the power supply unit is connected to a power input end of the control unit.

7. The signal amplifying circuit according to claim 4, characterized in that: The control circuit module further includes a current amplifying driving unit, an input end of the current amplifying driving unit is connected to an output end of the control unit, and an output end of the current amplifying driving unit is connected to the relay control unit.

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