CN205809757U - Dynamic pressure regulating device and signal amplification system - Google Patents

Abstract

The utility model provides a dynamic voltage regulating device and a signal amplification system. The dynamic voltage regulating device includes a signal receiving end for receiving an input signal. The dynamic voltage regulation device is used to generate a voltage regulation signal according to the input signal, adjust the power supply voltage according to the voltage regulation signal, generate the operating voltage of the amplifier, and provide it to the amplifier, wherein the voltage regulation signal and The strength of the input signal is related. Therefore, in the signal amplifying system provided by the present invention, the operating voltage provided to the amplifier varies with the intensity of the input signal. In this way, the power consumption can be reduced, the utilization rate of the power supply can be improved, the service life of the power supply can be extended, and the battery life and service life of the rechargeable battery can also be improved.

Description

Dynamic pressure regulating device and signal amplification system

technical field

The utility model relates to the communication field, in particular to a dynamic voltage regulating device and a signal amplifying system.

Background technique

An amplifier is a device that can amplify the voltage or power of an input signal, and is widely used in various devices such as communications, broadcasting, radar, television, and automatic control.

During the use of the existing amplifier, the output waveform may be distorted due to reasons such as excessive load. Therefore, in order to obtain the desired output power, ensure the similarity between the output signal and the original signal waveform, and reduce the distortion rate of the waveform, a higher voltage is usually provided for the amplifier. However, in practical applications, the strength of the original signal input to the amplifier may vary, so when the strength (eg, amplitude) of the original signal is small, if the voltage supplied to the amplifier is still maintained at a high value, then It will increase power consumption, reduce the utilization rate of power supply, and cause waste of energy.

Therefore, there is a need for a signal amplification system, which can adjust the voltage input to the amplifier according to the strength of the input signal, thereby reducing power consumption, improving the utilization rate of the power supply, and prolonging the service life of the power supply.

Utility model content

The problem solved by the utility model is to provide a signal amplification system, which can adjust the voltage input to the amplifier according to the intensity of the input signal, thereby reducing power consumption, improving the utilization rate of the power supply, and prolonging the service life of the power supply. In addition, when the power source is a rechargeable battery, the endurance time and service life of the rechargeable battery can also be improved.

In order to solve the above problems, an embodiment of the present invention provides a dynamic voltage regulating device, which includes a signal receiving end for receiving an input signal. The dynamic voltage regulation device is used to generate a voltage regulation signal according to the input signal, adjust the power supply voltage according to the voltage regulation signal, generate the operating voltage of the amplifier, and provide it to the amplifier, wherein the voltage regulation signal and The strength of the input signal is related.

Optionally, the dynamic voltage regulating device further includes: a signal conditioning device, configured to process the input signal to generate a first signal, the voltage value of the first signal is related to the strength of the input signal and less than a preset voltage value; a logic operation device, used to generate the voltage regulation signal according to the first signal and a reference signal generated by the signal conditioning device; and a voltage adjustment device, used to generate the voltage regulation signal according to the logic operation device The voltage regulation signal adjusts the power supply voltage.

Optionally, the signal conditioning device includes: a first operational amplifier, configured to inversely process the input signal; a second operational amplifier, configured to generate a second signal, wherein the second signal includes the first A part of the voltage value of the input signal after reverse processing by an operational amplifier that is less than the preset voltage value; and a third operational amplifier, configured to generate a third signal, wherein the third signal includes the voltage value of the input signal less than the preset voltage value.

Optionally, the dynamic voltage regulation device further includes a matching unit, configured to buffer the second signal and the third signal and combine them into the first signal.

Optionally, the logic operation device is configured to calculate a first voltage value according to the first signal and the reference signal, and output the voltage regulation signal according to the first voltage value.

Optionally, when the first voltage value is greater than 0.1V and less than 1V, the voltage value of the output voltage regulation signal is equal to the first voltage value; when the first voltage value is less than or equal to 0.1V, the output The voltage value of the voltage regulation signal is equal to 0.1V; and when the first voltage value is greater than or equal to 1V, the output voltage value of the voltage regulation signal is equal to 1V.

Optionally, the logic operation device includes a first terminal, a second terminal and a third terminal, wherein the first terminal of the logic operation device is coupled to the signal conditioning device for inputting the first terminal a signal; the second end of the logic operation device is used to input the reference signal; the third end of the logic operation device is coupled with the voltage adjustment device, and is used to adjust the voltage A signal is input to the voltage adjusting device.

Optionally, the voltage adjusting device includes a booster, and the booster includes a first terminal and a second terminal, wherein the first terminal of the booster is coupled to the logic operation device, The second terminal of the booster is coupled to a power supply.

The embodiment of the present invention also provides a signal amplification system, which includes: an amplifier; a power supply; and any one of the above-mentioned dynamic voltage regulating devices, wherein the amplifier is used to amplify the input signal, and the dynamic The voltage regulating device is used to adjust the voltage of the power supply according to the input signal, generate the working voltage of the amplifier and provide it to the amplifier.

Compared with the prior art, the technical solution of the utility model has the following advantages:

In the signal amplifying system provided by the utility model, a dynamic voltage regulating device is provided, and the dynamic voltage regulating device can adjust the power supply voltage according to the strength of the input signal input to the amplifier. Therefore, the operating voltage supplied to the amplifier varies with the input signal. In this way, the power consumption is reduced, the utilization rate of the power supply is improved and the service life of the power supply is prolonged. In addition, in the case that the power source is a rechargeable battery, the dynamic voltage regulating device can also improve the endurance time and service life of the rechargeable battery.

Further, the dynamic voltage regulation device also includes a signal conditioning device for processing the input signal. The signal processed by the signal conditioning device can not only be used to represent the intensity change of the input signal, but also its voltage value is lower than the preset voltage value, so that the operation process of the logic operation device can be simplified.

Description of drawings

Fig. 1 is a schematic diagram of modules of a signal amplification system provided by an embodiment of the present invention;

Fig. 2 is a schematic diagram of a signal conditioning device of a signal amplification system provided by an embodiment of the present invention;

3a to 3e are schematic diagrams of the principle of processing input signals by a signal conditioning device of a signal amplification system provided by an embodiment of the present invention;

Fig. 4 is a schematic diagram of a logic operation device of a signal amplification system provided by an embodiment of the present invention;

Fig. 5 is a schematic diagram of a voltage adjustment device of a signal amplification system provided by an embodiment of the present invention;

Fig. 6 is a schematic diagram of parameter setting of a signal conditioning device of a signal amplification system provided by an embodiment of the present invention; and

Fig. 7 is a schematic diagram of parameter setting of a logic operation device and a voltage adjustment device of a signal amplification system provided by an embodiment of the present invention.

detailed description

As mentioned in the background art, in order to reduce the waveform distortion rate, in the existing signal amplification system, a relatively high and fixed voltage is usually provided for the amplifier, which will increase power consumption, reduce the utilization rate and service life of the power supply. In view of the defects in the prior art, the utility model provides a signal amplification system, which includes: an amplifier for amplifying the input signal; a power supply for providing a power supply voltage; and a dynamic voltage regulating device for Generate a voltage regulation signal from the input signal, adjust the power supply voltage according to the voltage regulation signal, generate the operating voltage of the amplifier and provide it to the amplifier, wherein the voltage regulation signal is related to the strength of the input signal . Therefore, in the signal amplifying system provided by the present invention, the working voltage provided to the amplifier changes with the change of the input signal. In this way, the power consumption is reduced, the utilization rate of the power source is improved, and the service life is extended. In addition, when the power source is a rechargeable battery, the dynamic voltage regulating device provided by the utility model can also improve the endurance time and service life of the rechargeable battery.

In order to make the above purpose, features and advantages of the utility model more obvious and easy to understand, specific embodiments of the utility model will be described in detail below in conjunction with the accompanying drawings.

Referring to FIG. 1 , the embodiment of the present invention provides a signal amplification system 1 . The signal amplifying system 1 includes an amplifier 10 and a power supply 20, wherein the amplifier 10 is used to amplify an input signal (for example, the left channel signal Lin and the right channel signal Rin in FIG. 1 ), and the power supply 20 is used to provide voltage.

In some embodiments, the signal amplifying system is used in an audio playback device, and the amplifier 10 is used to amplify the input signal to drive a speaker to work.

In some embodiments, the power source 20 is a DC power source, such as a battery. The battery may include one battery or multiple batteries. In some embodiments, the power source 20 is a rechargeable battery.

The signal amplifying system 1 further includes a dynamic voltage regulating device 30, and the dynamic voltage regulating device 30 includes a signal receiving end (not labeled) for receiving the input signal.

In this embodiment, the input signal is an audio signal, and the audio signal includes a left channel signal Lin and a right channel signal Rin, and the dynamic voltage regulating device 30 includes two signal receiving terminals for respectively receiving The left channel signal Lin and the right channel signal Rin.

In some embodiments, the input signal can also be other types of signals. The dynamic voltage regulating device 30 may also include one or more than two signal receiving ends, and the number of signal receiving ends of the dynamic voltage regulating device 30 can be adjusted according to actual needs.

The dynamic voltage regulation device 30 is configured to generate a voltage regulation signal according to the input signal received by the signal receiving end, and adjust the voltage of the power supply 20 according to the voltage regulation signal to generate the working voltage of the amplifier 10. The voltage is provided to the amplifier 10, wherein the voltage regulation signal is related to the strength of the input signal. In this way, the operating voltage provided to the amplifier 10 varies with the input signal strength, thereby reducing power consumption, improving the utilization rate of the power supply 20 , and prolonging the service life of the power supply 20 . In addition, when the power source 20 is a rechargeable battery, the dynamic voltage regulation device 30 can also increase the endurance time and service life of the rechargeable battery.

Specifically, the dynamic voltage regulation device 30 includes a signal conditioning device 31 , a logic operation device 32 and a voltage regulation device 33 . Wherein, the signal conditioning device 31 is configured to process the input signal to generate a first signal, and the voltage value of the first signal is related to the intensity of the input signal. The logic operation device 32 is configured to generate the voltage regulation signal according to the first signal and the reference signal generated by the signal conditioning device 31 . The voltage adjustment device 33 is used for adjusting the power supply voltage according to the voltage regulation signal generated by the logic operation device 32 .

In some embodiments, as shown in FIG. 2 , the signal conditioning device 31 includes a first operational amplifier 311 , a second operational amplifier 312 and a third operational amplifier 313 .

In some embodiments, the first operational amplifier 311, the second operational amplifier 312, and the third operational amplifier 313 are dual operational amplifiers of the NJM2740 model, so as to realize the analysis of the left channel signals Lin and Processing of the right channel signal Rin.

The first operational amplifier 311 is used for reverse processing the input signal. As shown in FIG. 2 , the V- port of the first operational amplifier 311 is grounded to GND, and the V+ port inputs the power supply voltage VCC. The -InA port of the first computing unit 311 inputs the left channel signal Lin, the +InA port inputs the voltage Bias, and a first circuit 314 is provided between the -InA port and the OutA port. The first circuit 314 is a parallel circuit formed by a capacitor and a resistor, which is connected between the output terminal OutA and the input terminal −InA of the first operational amplifier 311 to form a feedback network. The voltage value of the voltage Bias mentioned here is half of the voltage value of the power supply voltage VCC. The phase of the left channel signal Lin is reversed after passing through the first operational amplifier 311 , that is, the phase of the signal output from the OutA port is opposite to that of the left channel signal input from the -InA port.

Similarly, the -InB port of the first operational amplifier 311 inputs the right channel signal Rin, the +InB port inputs the voltage Bias, and the first circuit 314 is also provided between the -InB port and the OutB port to form a feedback network. The phase of the signal output from the OutB port is opposite to that of the right channel signal input from the -InB port.

Therefore, the phase of the input signal is reversed after passing through the first operational amplifier 311 . For example, when the input signal is a sinusoidal signal as shown in FIG. 3a (wherein the horizontal axis represents time T and the vertical axis represents voltage V), the signal after reverse processing by the first operational amplifier 311 is as shown in FIG. 3b Show. It should be noted that here only a sinusoidal signal is taken as an example to illustrate the working principle of the first operational amplifier 311 . In practice, the input signal can be any signal with regular or irregular changes.

The second operational amplifier 312 is configured to generate a second signal, wherein the second signal includes a portion of the input signal reversely processed by the first operational amplifier 311 whose voltage value is less than a preset voltage value. In some embodiments, the preset voltage value is equal to the voltage Bias.

As shown in Figure 2, the V- port of the second operational amplifier 312 is grounded to GND, the V+ port inputs a power supply voltage VCC, and a second circuit 315 is arranged between the power supply voltage VCC and the V+ port, and the second The circuit 315 is composed of a capacitor to stabilize the voltage. The +InA port of the second operational amplifier 312 is used to input the left channel signal reversely processed by the first operational amplifier 311 , the -InA port is connected in parallel with the OutA port, and a diode is connected in series with the OutA port. Thus, the second operational amplifier 312 converts the part of the left channel signal whose voltage value is greater than the preset voltage value (for example, the part whose voltage value is greater than the voltage Bias) after the reverse processing of the first operational amplifier 311. part) to filter out, and only keep the part whose voltage value is less than the preset voltage value (for example, the part whose voltage value is less than the voltage Bias).

Similarly, the +InB port of the second operational amplifier 312 inputs the right channel signal reversely processed by the first operational amplifier 311, the -InB port is connected in parallel with the OutB port, and a diode is connected in series at the OutB port . Thus, the second operational amplifier 312 filters out the part of the right channel signal whose voltage value is greater than the preset voltage value after reverse processing by the first operational amplifier 311, and only retains the part whose voltage value is lower than the preset voltage value. The part where the voltage value is set. For example, the second operational amplifier 312 may filter out the part of the right channel signal whose voltage value is greater than the voltage Bias after reverse processing by the first operational amplifier 311, and only keep the part whose voltage value is smaller than the voltage Bias. part.

In the embodiment shown in FIG. 2 , the signal conditioning device 31 further includes a capacitance unit and a resistance unit matched with the first operational amplifier 311 , the second operational amplifier 312 and the third operational amplifier 313 , for isolating DC signals and impedance matching, and its specific values and connection methods will not be repeated here.

Thus, after the input signal passes through the second operational amplifier 312, a second signal is generated, and the second signal includes a voltage value of the input signal reversely processed by the first operational amplifier 311 that is less than the preset voltage value part. For example, when the signal reversely processed by the first operational amplifier 311 is as shown in FIG. 3 b , the second signal generated by the second operational amplifier 312 is as shown in FIG. 3 c .

The third operational amplifier 313 is used to generate a third signal, wherein the third signal includes a portion of the input signal whose voltage value is less than the preset voltage value. The function of the third operational amplifier 313 is similar to that of the second operational amplifier 312, the difference being that the input signals are different, wherein the signal input to the second operational amplifier 312 is reversely processed by the first operational amplifier 311 The final input signal is input to the third operational amplifier 313 is the input signal without reverse processing. In other words, the second operational amplifier 312 is used to filter out the part of the input signal whose voltage value is greater than the preset voltage value after being reversely processed by the first operational amplifier 311, and the third operational amplifier 313 directly processes the input signal to filter out a part of the input signal whose voltage value is greater than the preset voltage value.

The structure and function of the third operational amplifier 313 are similar to those of the second operational amplifier 312 and will not be repeated here.

Therefore, after the input signal passes through the third operational amplifier 313, a third signal is generated, and the third signal includes a part of the input signal whose voltage value is less than a preset voltage value. For example, when the input signal is a sinusoidal signal as shown in FIG. 3a, the third signal generated by the third operational amplifier 313 is as shown in FIG. 3d.

The first signal is obtained by combining the second signal generated by the first operational amplifier 311 and the second operational amplifier 312 with the third signal generated by the third operational amplifier 313 . For example, when the input signal is a sinusoidal signal as shown in FIG. 3a, the second signal generated by the first operational amplifier 311 and the second operational amplifier 312 is shown in FIG. The third signal generated by the three operational amplifiers 313 is shown in FIG. 3d, and the first signal obtained by combining the second signal and the third signal is shown in FIG. 3e. The first signal can be further used by the logic operation unit 32 to generate the voltage regulation signal.

In some embodiments, the signal conditioning device 31 further includes a matching unit 316 for buffering the first signal to match with the logic operation device 32 . The matching unit 316 includes a capacitor (not marked), so that the voltage V _PR changes smoothly. Specifically, considering that the operational amplifiers in the signal conditioning device 31 (that is, the first operational amplifier 311, the second operational amplifier 312, and the third operational amplifier 313) have a large input impedance and a small output impedance characteristics, by setting the matching unit 316, the voltage of the first signal generated by the signal conditioning device 31 can be made to drop quickly and rise gently, because the capacitor in the matching unit 316 needs to be charged when the voltage rises . In this way, the final output voltage of the voltage regulating device 30 rises quickly and drops gently.

The first signal generated by the signal conditioning device 31 is further input to the logic operation device 32 to generate the voltage regulation signal.

As shown in FIG. 4 , the logic operation device 32 includes a programmable logic device 321 whose model is SLG46140. The port VDD of the programmable logic device 321 is used to input the power supply voltage VCC, the port GND is grounded, and the sixth port GPIO is used to input the first signal generated by the signal conditioning device 31 (V _PR in FIG. 4 ), The seventh port GPIO is used to input a reference signal, and the voltage regulation signal is generated by comparing the first signal with the reference signal, and the voltage regulation signal (V _DAC in FIG. 4 ) is output from the third port GPIO. In addition, a third circuit 322 is provided between the power supply voltage VCC and the VDD port, and the third circuit 322 includes a capacitor to stabilize the circuit operating voltage VCC. A fourth circuit 323 is provided between the GND port and the seventh port GPIO, and the fourth circuit is used as a voltage divider network for determining a reference voltage value.

Specifically, the logic operation device 32 is configured to calculate a first voltage value according to the first signal and the reference signal, and output the voltage regulation signal according to the first voltage value. In some embodiments, when the first voltage value is greater than 0.1V and less than 1V, the voltage value of the output voltage regulation signal is equal to the first voltage value; when the first voltage value is less than or equal to 0.1V, The voltage value of the output voltage regulation signal is equal to 0.1V; and when the first voltage value is greater than or equal to 1V, the voltage value of the output voltage regulation signal is equal to 1V.

The voltage regulation signal generated by the logic operation device 32 is further input into the voltage regulation device 33 to adjust the operating voltage provided to the amplifier 10 .

In some embodiments, as shown in FIG. 5 , the voltage adjusting device 33 includes a booster 331 whose model is TPS61088. The VIN port of the booster 331 is coupled to the power supply 20, the FB port is coupled to the logic operation device 32 to input the voltage regulation signal V _DAC , the AGND port and the FGND port are grounded, and the VOUT port is used to output the amplifier 10 required for operating voltage V _OUT . Because the voltage at the FB port is maintained at a stable value, the sixth circuit 333 constitutes a voltage divider network, so that when the strength of the input signal changes, the voltage V _DAC of the voltage regulation signal changes accordingly, so the output The voltage V _OUT also changes accordingly. In this way, the dynamic adjustment of the voltage can be realized according to the intensity change of the input signal, so as to reduce power consumption and improve the utilization rate and service life of the power supply. In addition, a fifth circuit 332 is provided between the power supply 20 and the VIN port to stabilize the voltage. It should be noted that although FIG. 5 only shows the connection modes of the VIN port, the FB port, the VOUT port, the AGND port and the FGND port of the booster 331 of the voltage regulating device 33, those skilled in the art can It should be understood that the voltage adjusting device 33 may also include some other peripheral components.

As shown in Figure 6 and Figure 7, in an embodiment of the present utility model, the power supply voltage VCC is set to 3.3 volts, the voltage Bias is 1.65 volts, the first logic operation device 311, the second Both the logical operation device 312 and the third logical operation device 313 are two-way logical operation devices of the NJM2740 model. The parameters of the first circuit, the second circuit, the third circuit, the fourth circuit, the fifth circuit, the sixth circuit and the components in the matching unit are set as shown in the figure shown.

In this embodiment, the voltage value of the first signal generated by the conditioning circuit 31 and the input signal satisfy:

V _PR = (1.65-V _IN x 1.414)/1.133

Wherein, V _PR represents the voltage value of the first signal, and V _IN represents the root mean square of the voltage value of the input signal.

The relationship between the first voltage value V1 calculated by the logical operation device 32 and the first signal and the reference signal satisfies:

V1＝4*(V _PR -V _RF +0.05)

Wherein, V1 represents the first voltage value, V _PR represents the voltage value of the first signal, and V _RF represents the voltage value of the reference signal.

The voltage value V _DAC of the voltage regulation signal and the first voltage value V1 satisfy: when 0.1V≤V1≤1V, the voltage value V _DAC of the voltage regulation signal is equal to the first voltage value V1; When V1≤0.1V, the voltage value V _DAC of the voltage regulation signal is equal to 0.1V; when V1≥1V, the voltage value V _DAC of the voltage regulation signal is equal to 1V.

The voltage value V _OUT of the operating voltage output by the voltage adjusting device 33 and the voltage value V _DAC of the voltage regulation signal and the fifth circuit satisfy:

V _OUT ＝V _REF (1+R ₁₀₅ /R ₁₀₇ +R ₁₀₅ /R ₁₀₉ )-V _DAC *R ₁₀₅ /R ₁₀₉

Wherein, V _OUT represents the working voltage output by the voltage adjusting device 33 , V _REF represents the voltage value of the FB port, and V _DAC represents the voltage value of the voltage regulation signal.

In some embodiments, when the voltage V _DAC of the voltage regulation signal varies within a range of 0.1V to 1V, the power supply voltage V _OUT varies between 11.78V-5.03V.

It can be seen that, in the amplification system provided by the embodiment of the present invention, the operating voltage input to the amplifier 10 changes dynamically as the input signal changes, so as to reduce power consumption.

Although the utility model is disclosed as above, the utility model is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present utility model, so the protection scope of the present utility model should be based on the scope defined in the claims.

Claims (9)

1. A dynamic voltage regulation device, characterized in that it comprises: a signal receiving end for receiving an input signal, the dynamic voltage regulation device is used for generating a voltage regulation signal according to the input signal, and according to the voltage regulation signal The power supply voltage is adjusted, the working voltage of the amplifier is generated and provided to the amplifier, wherein the voltage regulation signal is related to the strength of the input signal. 2. The dynamic pressure regulating device according to claim 1, further comprising: A signal conditioning device, configured to process the input signal to generate a first signal, the voltage value of the first signal is related to the strength of the input signal and is smaller than a preset voltage value; a logic operation device, configured to generate the voltage regulation signal according to the first signal and the reference signal generated by the signal conditioning device; and A voltage adjustment device, configured to adjust the power supply voltage according to the voltage regulation signal generated by the logic operation device. 3. The dynamic voltage regulating device according to claim 2, wherein the signal conditioning device comprises: a first operational amplifier, configured to inversely process the input signal; A second operational amplifier, configured to generate a second signal, wherein the second signal includes a part where the voltage value of the input signal reversely processed by the first operational amplifier is less than the preset voltage value; and A third operational amplifier, configured to generate a third signal, wherein the third signal includes a portion of the input signal whose voltage value is less than the preset voltage value. 4. The dynamic voltage regulating device according to claim 3, further comprising a matching unit, configured to buffer the second signal and the third signal and combine them into the first signal. 5. The dynamic voltage regulating device according to claim 2, characterized in that, the logic operation device is used to calculate a first voltage value according to the first signal and the reference signal, and calculate the first voltage value according to the first voltage value, and output the voltage regulation signal. 6. The dynamic voltage regulation device according to claim 5, wherein when the first voltage value is greater than 0.1V and less than 1V, the output voltage value of the voltage regulation signal is equal to the first voltage value; When the first voltage value is less than or equal to 0.1V, the voltage value of the output voltage regulation signal is equal to 0.1V; and when the first voltage value is greater than or equal to 1V, the voltage value of the output voltage regulation signal is equal to 1V . 7. The dynamic voltage regulating device according to claim 2, wherein the logic operation device comprises a first terminal, a second terminal and a third terminal, wherein the first terminal of the logic operation device and The signal conditioning device is coupled to input the first signal; the second terminal of the logic operation device is used to input the reference signal; the third terminal of the logic operation device is connected to the The voltage adjustment device is coupled to input the voltage regulation signal to the voltage adjustment device. 8. The dynamic voltage regulating device according to claim 2, wherein the voltage regulating device comprises a booster, and the booster includes a first terminal and a second terminal, wherein the booster The first terminal is coupled to the logic operation device, and the second terminal of the booster is coupled to a power supply. 9. A signal amplification system, characterized in that it comprises: an amplifier; a power supply; and the dynamic voltage regulating device according to any one of claims 1-8, wherein the amplifier is used to amplify the input signal, and the The dynamic voltage regulating device is used to adjust the voltage of the power supply according to the input signal, generate the working voltage of the amplifier and provide it to the amplifier.