Tuning circuit and tuning equipment

Abstract

The utility model relates to the technical field of tuning, and discloses a tuning circuit and tuning equipment, and the circuit comprises a signal input end; the base electrode of the transistor is connected with the signal input end, the collector electrode of the transistor is connected with a reference voltage source, and the transistor outputs a target signal; and the frequency modulation RC network is used for carrying out frequency modulation on a signal output by the transistor and comprises a C-type potentiometer, the frequency modulation RC network is connected with a collector electrode of the transistor, and the other end of the frequency modulation RC network is connected with an emitter electrode of the transistor. The tuning device comprises a tuning circuit. According to the invention, the transistor and the C-type potentiometer are applied to the sound tuning circuit to realize high and low pitch adjustment and achieve the effect of high adjustment efficiency.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of tone adjustment, and particularly relates to a tone adjustment circuit and tone adjustment equipment. BACKGROUND

[0002] At present, the tone adjustment circuit unit is equipped in the sound on the market, so as to realize different tone adjustment functions to meet different hearing effects of users.

[0003] Most tone adjustment circuits use independent chips to control the change of high and low sounds, and have the problem of high cost; and some tone adjustment circuits use B-type potentiometers, the resistance value change of the B-type potentiometer has a linear relationship with the rotation angle, although the uniform resistance value change can be realized, the perception of the human ear to the sound loudness is not linear, and the human ear may feel that the adjustment is not sensitive enough at a low volume and is too sensitive at a high volume. On the other hand, the adjustment efficiency of the tone adjustment circuit of the B-type potentiometer is low in the high frequency region, and the frequency response adjustment is not smooth enough. SUMMARY

[0004] The present application provides a tone adjustment circuit and tone adjustment equipment, which can realize smooth hearing during tone adjustment and improve the efficiency of audio adjustment.

[0005] The tone adjustment circuit disclosed in the present application comprises:

[0006] a signal input end;

[0007] a transistor, a base of the transistor is connected with the signal input end, a collector of the transistor is connected with a reference voltage source, and a target signal is outputted; and

[0008] a frequency modulation RC network for frequency modulation of the signal outputted by the transistor, comprising a C-type potentiometer, the frequency modulation RC network is connected with the collector of the transistor, and the other end of the frequency modulation RC network is connected with an emitter of the transistor.

[0009] In an embodiment, the transistor is an N-type transistor.

[0010] In an embodiment, the reference voltage source comprises a power supply, a second electrolytic capacitor, a first resistor and a second resistor, the power supply is connected with the first resistor, the other end of the first resistor is respectively connected with the second resistor and the second electrolytic capacitor, the other end of the second resistor is respectively connected with the collector of the transistor and the frequency modulation RC network, and the other end of the second electrolytic capacitor is connected with a ground end.

[0011] In an embodiment, the tone circuit further comprises a third resistor, a first capacitor and a first electrolytic capacitor, the signal input end is connected to the base of the transistor through the first electrolytic capacitor, the first capacitor is connected to the second resistor, the third resistor, the frequency modulation RC network and the collector of the transistor respectively, and the other end of the first capacitor is connected to the first electrolytic capacitor, the other end of the third resistor and the base of the transistor.

[0012] In an embodiment, the frequency modulation RC network comprises a third electrolytic capacitor, a fourth electrolytic capacitor, a low-frequency RC network and a high-frequency RC network, the low-frequency RC network is connected to the third electrolytic capacitor and the high-frequency RC network, the other end of the low-frequency RC network is connected to the fourth electrolytic capacitor and the other end of the high-frequency RC network, the other end of the third electrolytic capacitor is connected to the collector of the transistor, and the other end of the fourth electrolytic capacitor is connected to the emitter of the transistor.

[0013] In an embodiment, the low-frequency RC network comprises a fourth resistor, a fifth resistor, a second capacitor, a third capacitor and a first C-type potentiometer, the fourth resistor is connected to the third electrolytic capacitor, the other end of the fourth resistor is connected to the first C-type potentiometer and the second capacitor, the other end of the second capacitor is connected to the control end of the first C-type potentiometer and the third capacitor respectively, the other end of the third capacitor is connected to the fifth resistor and the other end of the first C-type potentiometer respectively, and the other end of the fifth resistor is connected to the fourth electrolytic capacitor.

[0014] In an embodiment, the high-frequency RC network comprises a fourth capacitor, a sixth resistor, a seventh resistor and a second C-type potentiometer, the sixth resistor is connected between the third electrolytic capacitor and the fourth resistor, the other end of the sixth resistor is connected to the second C-type potentiometer, the fourth capacitor is connected to the control end of the second C-type potentiometer, the seventh resistor is connected to the other end of the second C-type potentiometer, and the other end of the seventh resistor is connected between the fifth resistor and the fourth electrolytic capacitor.

[0015] In an embodiment, the frequency modulation RC network further comprises an eighth resistor, the eighth resistor is connected to the first C-type potentiometer, the other end of the eighth resistor is connected to the other end of the fourth capacitor, and the ground end is connected between the eighth resistor and the fourth capacitor.

[0016] In an embodiment, the tone circuit further comprises a ninth resistor, the ninth resistor is connected between the fourth electrolytic capacitor and the emitter of the transistor, and the other end of the ninth resistor is connected to the ground end.

[0017] In an embodiment, the tone circuit further comprises a tenth resistor, the ninth resistor is connected between the first electrolytic capacitor and the base of the transistor, and the other end of the tenth resistor is connected to the ground end.

[0018] The application also discloses a tuning device comprising the tuning circuit according to any one of the above.

[0019] As can be seen from the above, the tuning circuit and the tuning device provided by the application can realize the gain improvement by applying the frequency modulation RC network containing the C-type potentiometer, and can realize smooth tuning and improve the tuning efficiency by cooperating with the transistor. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The tuning circuit provided by the embodiment of the application is shown in a structural schematic diagram.

[0021] Figure 2 Another structural schematic diagram of the tuning circuit provided by the embodiment of the application is shown.

[0022] Figure 3 The tuning device provided by the embodiment of the application is shown in a structural schematic diagram. DETAILED DESCRIPTION

[0023] The preferred embodiments of the application are described in detail below with reference to the accompanying drawings, so that the advantages and features of the application can be more easily understood by those skilled in the art, and the protection scope of the application can be more clearly defined.

[0024] Please refer to the drawings, wherein the same component symbols represent the same components, and the principles of the application are exemplified by being implemented in a suitable operating environment. The following description is based on the exemplified specific embodiments of the application, which should not be regarded as limiting other specific embodiments of the application which are not described in detail herein.

[0025] Please refer to Figure 1 , a structure of the tuning circuit provided by the embodiment of the application is shown.

[0026] As Figure 1 shown, the tuning circuit comprises a signal input end 1, a reference voltage source 2, a transistor 3, a frequency modulation RC network 4, and a C-type potentiometer 41.

[0027] The signal input end 1 of the tone circuit is connected with an external audio signal, so that the audio signal output by the device is connected to the signal input end 1 of the tone circuit through an audio line. The signal input end 1 is connected to the base of the transistor 3, which is specifically an N-type transistor, for the purpose of amplifying the input signal. The collector of the transistor 3 is connected to the reference voltage source 2 for outputting to the transistor 3 and providing a voltage of 12V. The frequency modulation RC network 4 is used for frequency modulation of the signal output by the transistor 3, for selection of the signal frequency, for affecting the input signal strength of the transistor 3 by changing the parameters thereof, for changing the base current, and for further affecting the collector current and the amplification factor of the transistor 3, so as to indirectly adjust the gain of the circuit.

[0028] The reference voltage source in the circuit can be a voltage stabilizer or a reference voltage chip. The implementation mode of the reference voltage source is only for example, and other implementation modes for providing a voltage of 12V to the circuit can also be used in actual application, so as to facilitate the use of the tone circuit, which is not limited in the application. The frequency modulation RC network 4 includes a C-type potentiometer 41, which can change the capacitance value in the frequency modulation RC network 4, so as to adjust the gain of the high and low frequency sound signals by this way, and realize the adjustment of the tone of the audio device.

[0029] As can be seen from the above, the working principle of the tone circuit in the application is that the signal enters from the signal input end 1 and is amplified by the transistor 3. The frequency modulation RC network 4 cooperates with the transistor 3 to form a feedback loop. In the circuit, the resistance value is changed by adjusting the C-type potentiometer, so that the parameters of the frequency modulation RC network are changed, so as to change the gain of the transistor 3 to the signal, realize the promotion or attenuation of the bass and treble, and further adjust the signal, and finally realize the change of the bass and treble.

[0030] Please refer to Figure 2 , which shows another structure of the tone circuit provided by the embodiment of the application.

[0031] As shown in Figure 2 , the reference voltage source includes a power supply, a second electrolytic capacitor EC2, a first resistor R1, and a second resistor R2. The power supply is connected to the first resistor R1. The other end of the first resistor R1 is respectively connected to the second resistor R2 and the second electrolytic capacitor EC2. The other end of the second resistor R2 is respectively connected to the collector of the transistor Q1 and the frequency modulation RC network. The other end of the second electrolytic capacitor EC2 is connected to the ground end.

[0032] The first resistor R1 is a power supply current-limiting resistor, the power output end is connected with the first resistor R1, and the first resistor R1 can protect the power supply itself and various circuits and devices connected to the power supply from damage caused by load short circuit and the like. The second electrolytic capacitor EC2 is used for filtering out ripples in the power supply, providing a stable DC power supply for the amplifier, reducing noise and interference in the audio signal, and improving the quality of the audio output.

[0033] Further, the tone control circuit further comprises a third resistor R3, a first capacitor C1 and a first electrolytic capacitor EC1, the signal input end is coupled with the base of the transistor Q1 through the first electrolytic capacitor EC1, the first capacitor C1 is connected with the second resistor R2, the third resistor R3, the frequency modulation RC network and the collector of the transistor Q1 respectively, and the other end of the first capacitor C1 is connected with the first electrolytic capacitor EC1, the other end of the third resistor R3 and the base of the transistor Q1.

[0034] Specifically, the first electrolytic capacitor EC1 is used for isolating a DC signal and allowing an AC audio signal to pass through and be transmitted to the base of the transistor Q1. The first capacitor C1 can bypass a high-frequency self-oscillation signal to the ground, avoiding the high-frequency self-oscillation signal from forming positive feedback in the circuit, thereby eliminating self-oscillation. The third resistor R3 is a bias resistor used for controlling the base current of the transistor Q1. By adjusting the resistance value of the bias resistor, the amplification factor of the transistor Q1 can reach the value required by the tone control circuit, so as to achieve appropriate amplification of the audio signal and flexible adjustment of the gain of the transistor Q1, ensuring that the output signal can be fully amplified and avoiding overload or distortion of the tone control circuit.

[0035] The frequency modulation RC network comprises a third electrolytic capacitor EC3, a fourth electrolytic capacitor EC4, a low-frequency RC network and a high-frequency RC network. The low-frequency RC network is connected with the third electrolytic capacitor EC3 and the high-frequency RC network, the other end of the low-frequency RC network is connected with the fourth electrolytic capacitor EC4 and the other end of the high-frequency RC network, the other end of the third electrolytic capacitor EC3 is connected with the collector of the transistor Q1, and the other end of the fourth electrolytic capacitor EC4 is connected with the emitter of the transistor Q1.

[0036] Specifically, the low-frequency RC network includes a fourth resistor R4, a fifth resistor R5, a second capacitor C2, a third capacitor C3, and a first C-type potentiometer VR1. The fourth resistor R4 is connected to the third electrolytic capacitor EC3. The other end of the fourth resistor R4 is connected to the first C-type potentiometer VR1 and the second capacitor C2. The other end of the second capacitor C2 is connected to the control end of the first C-type potentiometer VR1 and the third capacitor C3, respectively. The other end of the third capacitor C3 is connected to the fifth resistor R5 and the other end of the first C-type potentiometer VR1, respectively. The first C-type potentiometer VR1 is a key element for low-frequency adjustment, and its resistance changes logarithmically with the rotation angle. The third electrolytic capacitor EC3 is usually used for preliminary filtering and coupling of the input signal, so that the signal can be stably transmitted to the subsequent circuit, and the collector of the transistor Q1 is connected to the signal output end through the third electrolytic capacitor EC3. The other end of the fifth resistor R5 is connected to the fourth electrolytic capacitor EC4. The fifth resistor R5 functions as current limiting and voltage dividing in the circuit, and together with other elements, it affects the transmission and adjustment of low-frequency signals.

[0037] In addition, the high-frequency RC network includes a fourth capacitor C4, a sixth resistor R6, a seventh resistor R7, and a second C-type potentiometer VR2. The sixth resistor R6 is connected between the third electrolytic capacitor EC3 and the fourth resistor R4. The other end of the sixth resistor R6 is connected to the second C-type potentiometer VR2. The sixth resistor R6 obtains a part of the signal from the input signal for high-frequency adjustment. The second C-type potentiometer VR2 is also a logarithmic potentiometer for high-frequency adjustment. The fourth capacitor C4 is connected to the control end of the second C-type potentiometer VR2. The seventh resistor R7 is connected to the other end of the second C-type potentiometer VR2. The other end of the seventh resistor R7 is connected between the fifth resistor R5 and the fourth electrolytic capacitor EC4. The seventh resistor R7 and other elements together form a high-frequency filter network to attenuate or boost high-frequency signals. The control end of the above-mentioned potentiometer can be a slide piece. The frequency-adjusting RC network further includes an eighth resistor R8 connected to the first C-type potentiometer VR1 and the other end connected to the other end of the fourth capacitor C4. The eighth resistor R8 functions as isolation and current limiting, and together with the fourth capacitor C4, it affects the overall frequency response of the circuit. The ground end is connected between the eighth resistor R8 and the fourth capacitor C4 to provide a stable reference potential for the circuit, ensuring normal operation of the circuit.

[0038] The above-mentioned frequency-adjusting RC network uses C-type potentiometers, which can more finely adjust the low-frequency and high-frequency parts of the audio signal according to the perceptual characteristics of the human ear to sound. By adjusting the sliding points of the first C-type potentiometer VR1 and the second C-type potentiometer VR2 from bottom to top, the audio is further attenuated by gradually increasing impedance. When the sliding points are adjusted from top to bottom, the audio is boosted, thereby achieving the adjustment of the tone. The high-efficiency tuning circuit of the present application uses basic and common elements, is suitable for tuning applications of various audio devices, and has a relatively low price, easy to obtain, and achieves the effect of reducing product cost.

[0039] The tuning circuit further comprises a ninth resistor R9 and a tenth resistor R10, the ninth resistor R9 is connected between the fourth electrolytic capacitor EC4 and the emitter of the transistor Q1, the other end of the ninth resistor R9 is connected with the ground terminal, the ninth resistor R9 produces adjustment effect on the base current, thereby inhibiting the change of the collector current, stabilizing the working state of the transistor Q1, and improving the stability of the circuit, while the tenth resistor R10 cooperates with the third resistor R3 to provide a suitable DC bias voltage for the base of the transistor Q1, and the tenth resistor R10 makes the base voltage not rise too much through voltage division, thereby avoiding the substantial increase of the base current, protecting the transistor Q1, and also playing a role in preventing overloading in the circuit.

[0040] Referring to Figure 3 , the structure of the tuning device provided in the embodiments of the present application is shown in the figure.

[0041] As shown in Figure 3 , the tuning device 100 comprises a tuning circuit 110, the tuning device 100 can be used for adjusting the pitch, volume, tone and the like of an audio signal, and is suitable for various audio scenes, and the tuning device can be a sound box or an earphone, which is not limited in the present application. Specifically, in addition to the tuning circuit 110, the tuning device 100 can further comprise an audio input module, an audio output module, a control module, a power module, and a device shell and the like structural components. The structural components can enable the tuning device 100 to normally work, and the specific structure and model thereof can be determined according to actual needs.

[0042] The tuning device 100 described above utilizes the tuning circuit 110, which can avoid using independent chips to achieve the effect of signal tuning, and the basic circuit elements increase the stability of the structure while saving the cost of hardware, thereby reducing the cost of the product.

[0043] The term "module" used herein can be a software or hardware object executing on the computing system. Different components, modules, engines, and services described herein can be implemented as executing objects on the computing system. The apparatuses and methods described herein can be implemented in software, and of course, can be implemented in hardware, all within the scope of the present application.

[0044] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As will be apparent to those of ordinary skill in the art, embodiments described herein can be combined with other embodiments.

[0045] In the description of the application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected, or can communicate with each other; can be directly connected, or indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0046] The embodiments of the application are described in detail above in combination with the drawings, but the application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

Claims

1. A tuning circuit, characterized by The circuit comprises: a signal input end; a transistor, a base of the transistor being connected with the signal input end, a collector of the transistor being connected with a reference voltage source, and outputting a target signal; and a frequency modulation RC network for frequency modulating the signal outputted by the transistor, comprising a C-type potentiometer, the frequency modulation RC network being connected with the collector of the transistor, and another end of the frequency modulation RC network being connected with an emitter of the transistor.

2. The tuning circuit of claim 1, wherein, The transistor is an N-type transistor.

3. The tuning circuit of claim 1, wherein, The reference voltage source comprises a power supply, a second electrolytic capacitor, a first resistor, and a second resistor, the power supply being connected with the first resistor, another end of the first resistor being connected with the second resistor and the second electrolytic capacitor respectively, another end of the second resistor being connected with the collector of the transistor and the frequency modulation RC network respectively, and another end of the second electrolytic capacitor being connected with a ground end.

4. The tuning circuit of claim 3, wherein, The tone circuit further comprises a third resistor, a first capacitor, and a first electrolytic capacitor, the signal input end being connected with the base of the transistor through the first electrolytic capacitor, the first capacitor being connected with the second resistor, the third resistor, the frequency modulation RC network, and the collector of the transistor respectively, another end of the first capacitor being connected with the first electrolytic capacitor, another end of the third resistor, and the base of the transistor.

5. The tuning circuit of claim 1, wherein, The frequency modulation RC network comprises a third electrolytic capacitor, a fourth electrolytic capacitor, a low-frequency RC network, and a high-frequency RC network, the low-frequency RC network being connected with the third electrolytic capacitor and the high-frequency RC network, another end of the low-frequency RC network being connected with the fourth electrolytic capacitor and another end of the high-frequency RC network, another end of the third electrolytic capacitor being connected with the collector of the transistor, and another end of the fourth electrolytic capacitor being connected with the emitter of the transistor.

6. The tuning circuit of claim 5, wherein, The low-frequency RC network comprises a fourth resistor, a fifth resistor, a second capacitor, a third capacitor, and a first C-type potentiometer, the fourth resistor being connected with the third electrolytic capacitor, another end of the fourth resistor being connected with the first C-type potentiometer and the second capacitor, another end of the second capacitor being connected with a control end of the first C-type potentiometer and the third capacitor respectively, another end of the third capacitor being connected with the fifth resistor and another end of the first C-type potentiometer respectively, and another end of the fifth resistor being connected with the fourth electrolytic capacitor.

7. The tuning circuit of claim 6, wherein, The high-frequency RC network comprises a fourth capacitor, a sixth resistor, a seventh resistor, and a second C-type potentiometer, the sixth resistor being connected between the third electrolytic capacitor and the fourth resistor, another end of the sixth resistor being connected with the second C-type potentiometer, the fourth capacitor being connected with a control end of the second C-type potentiometer, the seventh resistor being connected with another end of the second C-type potentiometer, and another end of the seventh resistor being connected between the fifth resistor and the fourth electrolytic capacitor. The frequency modulation RC network further comprises an eighth resistor, the eighth resistor being connected with the first C-type potentiometer, another end of the eighth resistor being connected with another end of the fourth capacitor, and a ground end being connected between the eighth resistor and the fourth capacitor.

8. The tuning circuit of claim 6, wherein, The tone adjusting circuit further comprises a ninth resistor connected between the fourth electrolytic capacitor and the transistor emitter, and the other end of the ninth resistor is connected with the ground terminal.

9. The tuning circuit of claim 4, wherein, The tone adjusting circuit further comprises a tenth resistor connected between the first electrolytic capacitor and the transistor base, and the other end of the tenth resistor is connected with the ground terminal.

10. A tuning device, characterized by The tone adjusting device comprises the tone adjusting circuit according to any one of claims 1-9.

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