Front-stage input circuit system based on 48V phantom power supply and gain switch

Abstract

A front-stage input circuit system based on a 48V phantom power supply and a gain switch comprises a microphone input circuit module, a microphone amplification circuit module, a DSP processing circuit module, a power amplification circuit module, a DC boost module, a first-stage triode voltage stabilizing circuit module, a second-stage triode voltage stabilizing circuit module, a switch circuit module and an MCU control circuit module. The DC boosting module is connected with the first-stage triode voltage stabilizing circuit module; according to the utility model, the DC boost circuit module is connected with the DC-DC chip to carry out boost conversion processing, 48V voltage required by a system is output and obtained, the 48V voltage generated by the DC boost circuit module is accompanied with part of ripples, and the first-stage triode voltage stabilizing circuit module further filters the ripples of the switching power supply, so that the power supply is cleaner, and the power supply is more stable. And the power supply is filtered by the triode base RC circuit to obtain a clean power supply required by the system.

Description

Technical Field

[0001] The utility model relates to the technical field of audio, in particular to a front-stage input circuit system based on a 48V phantom power supply and a gain switch. Background Art

[0002] Speakers are commonly used electronic devices for modern audio playback. They can cooperate with other devices to play audio and bring auditory enjoyment to people. Among them, phantom power is a technology that provides power for audio equipment, mainly used for condenser microphones and other devices that require power drive. It usually transmits power through audio cables, thereby reducing the complexity of the equipment and avoiding the use of independent power supplies or batteries. Phantom power utilizes the unused space in the audio signal transmission line to provide power. In the phantom power system, two conductors of the transmission line are used to transmit audio signals, while the third conductor is used to provide power. This method makes the connection between devices easier and can also save costs and space. 48V phantom power is a common type of phantom power, which is widely used in professional audio equipment and studio recording environments. This type of phantom power provides stable voltage and current. Due to its working principle, condenser microphones need to provide power to work properly, and condenser microphones have the characteristics of high sensitivity. In view of the characteristics of condenser microphones, the input circuit with 48V phantom power needs to have high gain. The high-gain circuit, plus the phantom power switch and gain switch, is prone to noise. There is an impact sound when the switch is turned on and off. In particular, the circuit with 48V phantom power needs to be more perfect in design. This type of phantom power provides stable voltage and current to meet the needs of high-quality microphones and other equipment, and solves the problem of impact sound when the switch is turned on and off. Utility Model Content

[0003] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of the utility model is to provide a pre-stage input circuit system based on a 48V phantom power supply and a gain switch.

[0004] The technical solution adopted by the utility model to solve the technical problem is: a front-stage input circuit system based on a 48V phantom power supply and a gain switch, comprising a microphone input circuit module, a microphone amplifier circuit module, a DSP processing circuit module, a power amplifier circuit module, a first-stage triode voltage stabilizing circuit module, a DC boost module, a second-stage triode voltage stabilizing circuit module, a switch circuit module and an MCU control circuit module, wherein the DC boost module is connected to the first-stage triode voltage stabilizing circuit module, the second-stage triode voltage stabilizing circuit module and the switch circuit module are connected to the MCU control circuit module and the microphone input circuit module, and the microphone input circuit module is connected to the microphone amplifier circuit module and the gain switch module.

[0005] As a further improvement of the utility model: the microphone amplifier circuit module is connected to the DSP circuit module.

[0006] As a further improvement of the utility model: the DSP circuit module is connected to the power amplifier circuit module.

[0007] As a further improvement of the utility model: the DC boost module is connected to the second-stage triode voltage stabilizing circuit module and the switch circuit module.

[0008] As a further improvement of the utility model: the DC boost circuit module is provided with an inductor L4 and a transformer U2, one end of the inductor L4 is connected to a 24V voltage, the other end of the inductor L4 is connected to the second pin input end of the transformer U2, and resistors R6 and R7 are connected to D1.

[0009] As a further improvement of the present invention: the transformer U2 is connected to a DC-DC chip.

[0010] As a further improvement of the present utility model: the second-stage triode voltage stabilizing circuit module is provided with a SW2 switch and an RC filter circuit, and the SW2 switch is connected to the RC filter circuit and the MCU circuit.

[0011] As a further improvement of the present utility model: the second-stage triode voltage stabilizing circuit module is provided with a SW2 switch and an RC filter circuit, and the SW2 switch is connected to the RC filter circuit and the MCU module.

[0012] As a further improvement of the present invention: the microphone input circuit module is provided with a JK1 input terminal and a JK2 input terminal.

[0013] As a further improvement of the present utility model: the JK1 input end is connected to resistor R15, resistor R16, inductor L2 and inductor L3, the inductor L2 and inductor L3 are connected to resistor R2 and resistor R3, the JK2 input end is connected to inductor L1, and the inductor L1 is connected to resistor R17.

[0014] As a further improvement of the present invention: the resistor R17, the resistor R2, and the resistor R3 are connected to the 5th and 6th pins of the transformer U1.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. The utility model connects the DC-DC chip to perform boost conversion processing through the DC boost circuit module, and outputs the 48V voltage required by the system. The 48V voltage generated by the DC boost circuit module will be accompanied by some ripples. The first-stage transistor voltage regulator circuit module further filters out the ripple of the switching power supply to make the power supply cleaner. The power supply is filtered through the transistor base RC circuit to obtain the clean power supply required by the system.

[0017] 2. The utility model adopts a second-stage triode voltage-stabilizing circuit module and a switch circuit module. The second-stage triode voltage-stabilizing circuit module is combined with a switch to solve the impact sound generated when the phantom power is switched on and off. The impact sound generated by the opening and closing of the SW2 switch in the circuit is reduced by the RC filter circuit of the triode and the MCU module according to the actual circuit value, and the MCU module performs mute control on the DSP module and the power amplifier module when the phantom power is turned on and off, thereby solving the impact sound generated when the phantom power is switched on and off. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of the utility model;

[0019] Figure 2 This is a schematic diagram of a circuit module of the utility model;

[0020] Figure 3 This is a schematic diagram of a DC boost circuit module of the utility model;

[0021] Figure 4 It is a schematic diagram of a primary triode voltage stabilizing circuit module of the utility model;

[0022] Figure 5 It is a schematic diagram of a secondary transistor voltage stabilizing circuit module and a switch circuit of the utility model;

[0023] Figure 6 This is a schematic diagram of a microphone input circuit module of the utility model;

[0024] Figure 7 This is a schematic diagram of a microphone amplifier circuit module of the utility model;

[0025] In the figure: 1. Microphone input circuit module; 2. Microphone amplifier circuit module; 3. DSP processing circuit module; 4. Power amplifier circuit module; 5. First-stage triode voltage regulator circuit module; 6. DC boost module; 7. Second-stage triode voltage regulator circuit module; 8. Switch circuit module; 9. MCU control circuit module; 10. Gain switch module. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in combination with the specific embodiments of the utility model and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] The utility model is further described in conjunction with the accompanying drawings and embodiments: Figure 1-7 A front-stage input circuit system based on a 48V phantom power supply and a gain switch is shown, comprising a microphone input circuit module 1, a microphone amplifier circuit module 2, a DSP processing circuit module 3, a power amplifier circuit module 4, a first-stage triode voltage regulator circuit module 5, a DC boost module 6, a second-stage triode voltage regulator circuit module 7, a switch circuit module 8 and an MCU control circuit module 9, wherein the DC boost module 6 is connected to the first-stage triode voltage regulator circuit module 5, the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8 are connected to the MCU control circuit module 9 and the microphone input circuit module 1, and the microphone input circuit module 1 is connected to the microphone amplifier circuit module 2 and the gain switch module 10.

[0030] As a preferred implementation, the microphone amplifier circuit module 2 is connected to the DSP circuit module 3 .

[0031] As a preferred implementation, the DSP circuit module 3 is connected to a power amplifier circuit module.

[0032] As a preferred implementation, the DC boost module 6 is connected to the second-stage transistor voltage stabilizing circuit module 7 and the switch circuit module 8 .

[0033] As a preferred embodiment, the DC boost circuit module 6 is provided with an inductor L4 and a transformer U2, one end of the inductor L4 is connected to a 24V voltage, the other end of the inductor L4 is connected to a second pin input end of the transformer U2, and resistors R6 and R7 are connected to D1.

[0034] As a preferred implementation, the transformer U2 is connected to a DC-DC chip.

[0035] As a preferred implementation, the second-stage transistor voltage stabilizing circuit module is provided with a SW2 switch and an RC filter circuit, and the SW2 switch is connected to the RC filter circuit and the MCU circuit.

[0036] As a preferred implementation, the second-stage transistor voltage stabilizing circuit module 7 is provided with a SW2 switch and an RC filter circuit, and the SW2 switch is connected to the RC filter circuit and the MCU module.

[0037] As a preferred implementation, the microphone input circuit module 1 is provided with a JK1 input terminal and a JK2 input terminal.

[0038] As a preferred implementation, the JK1 input terminal is connected to resistors R15, R16, inductors L2 and L3, the inductors L2 and L3 are connected to resistors R2 and R3, the JK2 input terminal is connected to inductor L1, and the inductor L1 is connected to resistor R17.

[0039] As a preferred implementation, the resistor R17 , the resistor R2 , and the resistor R3 are connected to the 5th and 6th pins of the transformer U1 .

[0040] The working principle of this utility model:

[0041] The utility model connects a DC-DC chip to a DC boost circuit module for boost conversion processing, and outputs a 48V voltage required by the system. The 48V voltage generated by the DC boost circuit module will be accompanied by some ripples. The first-stage triode voltage regulator circuit module further filters out the ripple of the switching power supply to make the power supply cleaner. The power supply is filtered through a triode base RC circuit to obtain a clean power supply required by the system. A second-stage triode voltage regulator circuit module and a switch circuit module are adopted, and the second-stage triode voltage regulator circuit module is combined with a switch and an MCU module for mute control to solve the impact sound generated when the phantom power is switched on and off. The impact sound generated by the opening and closing of the SW2 switch in the circuit is reduced by the RC filter circuit of the triode and the MCU module according to the actual circuit value, and the MCU module performs mute control on the DSP module and the power amplifier module when the phantom power is turned on and off, so as to solve the impact sound generated when the phantom power is switched on and off.

[0042] Implementation case 1:

[0043] like Figure 1-7A front-stage input circuit system based on a 48V phantom power supply and a gain switch is shown, comprising a microphone input circuit module 1, a microphone amplifier circuit module 2, a DSP processing circuit module 3, a power amplifier circuit module 4, a first-stage triode voltage regulator circuit module 5, a DC boost module 6, a second-stage triode voltage regulator circuit module 7, a switch circuit module 8 and an MCU control circuit module 9, wherein the DC boost module 6 is connected to the first-stage triode voltage regulator circuit module 5, the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8 are connected to the MCU control circuit module 9 and the microphone input circuit module 1, and the microphone input circuit module 1 is connected to the microphone amplifier circuit module 2 and the gain switch module 10.

[0044] The microphone amplifier circuit module 2 is connected to the DSP circuit module 3, the DSP circuit module 3 is connected to the power amplifier circuit module, the DC boost module 6 is connected to the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8, the DC boost circuit module 6 is provided with an inductor L4 and a transformer U2, one end of the inductor L4 is connected to a 24V voltage, the other end of the inductor L4 is connected to the second pin input end of the transformer U2, the transformer U2 is connected to a DC-DC chip, the second-stage triode voltage regulator circuit module is provided with a SW2 switch and an RC filter circuit, the SW2 switch is connected to the RC filter circuit and the MC U circuit, resistors R6 and R7 are connected to D1, the second-stage transistor voltage stabilizing circuit module 7 is provided with a SW2 switch and an RC filter circuit, the SW2 switch is connected to the RC filter circuit, the microphone input circuit module 1 is provided with a JK1 input terminal and a JK2 input terminal, the JK1 input terminal is connected to resistors R15, R16, inductor L2 and L3, the inductor L2 and L3 are connected to resistors R2 and R3, the JK2 input terminal is connected to inductor L1, the inductor L1 is connected to resistor R17, the resistor R17, resistor R2, and resistor R3 are connected to the 5th and 6th pins of transformer U1.

[0045] In this embodiment, the circuit is connected by a DC boost module 6 with a first-stage triode voltage regulator circuit module 5, and then connected with a second-stage triode voltage regulator circuit module 7 and a switch circuit module 8. The second-stage triode voltage regulator circuit module 7 and the switch circuit module 8 are simultaneously connected with an MCU control circuit module 9 and a microphone input circuit module 1. The microphone input circuit module 1 is connected with a microphone amplifier circuit module 2 and a gain switch module 10. The microphone amplifier circuit module 2 is connected with a DSP circuit module 3, and the DSP circuit module 3 is connected with a power amplifier circuit module 4. The DC boost module 6 is a 24V voltage that passes through an inductor L4 and enters the second pin input end of the transformer U2, enters the DC-DC chip for boost conversion processing, and outputs a 48V voltage required by the system.

[0046] Implementation case 2:

[0047] like Figure 1-7 A front-stage input circuit system based on a 48V phantom power supply and a gain switch is shown, comprising a microphone input circuit module 1, a microphone amplifier circuit module 2, a DSP processing circuit module 3, a power amplifier circuit module 4, a first-stage triode voltage regulator circuit module 5, a DC boost module 6, a second-stage triode voltage regulator circuit module 7, a switch circuit module 8 and an MCU control circuit module 9, wherein the DC boost module 6 is connected to the first-stage triode voltage regulator circuit module 5, the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8 are connected to the MCU control circuit module 9 and the microphone input circuit module 1, and the microphone input circuit module 1 is connected to the microphone amplifier circuit module 2 and the gain switch module 10.

[0048] The microphone amplifier circuit module 2 is connected to the DSP circuit module 3, the DSP circuit module 3 is connected to the power amplifier circuit module, the DC boost module 6 is connected to the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8, the DC boost circuit module 6 is provided with an inductor L4 and a transformer U2, one end of the inductor L4 is connected to a 24V voltage, the other end of the inductor L4 is connected to the second pin input end of the transformer U2, the transformer U2 is connected to a DC-DC chip, and the second-stage triode voltage regulator circuit module 7 is provided with an S W2 switch and RC filter circuit, the SW2 switch is connected to the RC filter circuit and the MCU module, the microphone input circuit module 1 is provided with a JK1 input terminal and a JK2 input terminal, the JK1 input terminal is connected to the R15 resistor, the R16 resistor, the inductor L2 and the inductor L3, the inductor L2 and the inductor L3 are connected to the resistor R2 and the resistor R3, the JK2 input terminal is connected to the inductor L1, the inductor L1 is connected to the resistor R17, the resistor R17, the resistor R2, and the resistor R3 are connected to the 5th and 6th pins of the transformer U1.

[0049] In the first-stage triode voltage stabilizing circuit module 5 of the present embodiment, the 48V voltage generated by the DC boost module 6 will be accompanied by some ripples. The first-stage triode voltage stabilizing circuit module 5 further filters out the ripples of the switching power supply to make the power supply cleaner. The power supply is filtered through the triode base RC circuit to obtain the clean power supply required by the system. The second-stage triode voltage stabilizing circuit module 7 and the switch circuit module 8 solve the impact sound generated when the phantom power is switched on and off by combining the second-stage triode voltage stabilizing circuit module 7 with the switch; the impact sound generated by the opening and closing of the SW2 switch in the circuit is reduced by the RC filtering circuit of the triode and the MCU module according to the actual circuit value, and the MCU module performs mute control on the DSP module and the power amplifier module when the phantom power is turned on and off, so as to solve the impact sound generated when the phantom power is turned on and off.

[0050] Implementation case three:

[0051] like Figure 1-7 A front-stage input circuit system based on a 48V phantom power supply and a gain switch is shown, comprising a microphone input circuit module 1, a microphone amplifier circuit module 2, a DSP processing circuit module 3, a power amplifier circuit module 4, a first-stage triode voltage regulator circuit module 5, a DC boost module 6, a second-stage triode voltage regulator circuit module 7, a switch circuit module 8 and an MCU control circuit module 9, wherein the DC boost module 6 is connected to the first-stage triode voltage regulator circuit module 5, the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8 are connected to the MCU control circuit module 9 and the microphone input circuit module 1, and the microphone input circuit module 1 is connected to the microphone amplifier circuit module 2 and the gain switch module 10.

[0052] The microphone amplifier circuit module 2 is connected to the DSP circuit module 3, the DSP circuit module 3 is connected to the power amplifier circuit module, the DC boost module 6 is connected to the second-stage triode voltage regulator circuit module 7 and the switch circuit module 8, the DC boost circuit module 6 is provided with an inductor L4 and a transformer U2, one end of the inductor L4 is connected to a 24V voltage, the other end of the inductor L4 is connected to the second pin input end of the transformer U2, the transformer U2 is connected to a DC-DC chip, the second-stage triode voltage regulator circuit module 7 is provided with a SW2 switch and an RC filter circuit, the SW2 switch is connected to the RC filter circuit, the microphone input circuit module 1 is provided with a JK1 input end and a JK2 input end, the JK1 input end is connected to the R15 resistor, the R16 resistor, the inductor L2 and the inductor L3, the inductor L2 and the inductor L3 are connected to the resistor R2 and the resistor R3, the JK2 input end is connected to the inductor L1, the inductor L1 is connected to the resistor R17, the resistor R17, the resistor R2, and the resistor R3 are connected to the 5th and 6th pins of the transformer U1.

[0053] In this embodiment, the microphone input circuit module 1 is input from the JK1 or JK2 terminal. The signal is input from JK1, passes through resistors R15, R16, L2, and L3, and enters the microphone amplifier circuit module 2; and the signal is input from the JK2 terminal, passes through the inductor L1, and enters the microphone amplifier circuit module 2 for processing. The signal enters the microphone amplifier circuit module 2 from the JK1 and JK2 terminals, and the signal enters the operational amplifier from the resistors R17, R2, and R3 through the 5th and 6th pins of the transformer U1, and is output from the 1st and 7th pins of the operational amplifier. When the gain switch module 10 is pressed, the gain of the microphone can be adjusted. Adding a parallel resistor in the gain switch module 10 can solve the impact sound when the gain switch module 10 is pressed.

[0054] The main functions of this utility model:

[0055] The utility model connects a DC-DC chip to a DC boost circuit module for boost conversion processing, and outputs a 48V voltage required by the system. The 48V voltage generated by the DC boost circuit module will be accompanied by some ripples. The first-stage triode voltage regulator circuit module further filters out the ripple of the switching power supply to make the power supply cleaner. The power supply is filtered through a triode base RC circuit to obtain a clean power supply required by the system. The second-stage triode voltage regulator circuit module and the switch circuit module are adopted, and the second-stage triode voltage regulator circuit module is combined with a switch to solve the impact sound generated when the phantom power is switched on and off. The impact sound generated by the opening and closing of the SW2 switch in the circuit is reduced by the RC filtering circuit of the triode and the MCU control module according to the actual circuit value, and the MCU module performs mute control on the DSP module and the power amplifier module when the phantom power is turned on and off, so as to solve the impact sound generated when the phantom power is switched on and off.

[0056] In summary, after reading the utility model document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the utility model without creative mental labor, which all fall within the scope of protection of the utility model.

[0057] In the description of the present utility model, it needs to be understood that the orientations or positional relationships indicated by terms such as "upper end face", "lower end face", "top", "bottom", "left" and "right" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present utility model. Therefore, they cannot be understood as limitations on the actual use direction of the present utility model.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and should all be included in the scope of the claims and specification of the present invention.

Claims

1. A pre-stage input circuit system based on 48V phantom power supply and gain switch, characterized in that: It includes a microphone input circuit module, a microphone amplifier circuit module, a DSP processing circuit module, a power amplifier circuit module, a first-stage triode voltage stabilizing circuit module, a DC boost module, a second-stage triode voltage stabilizing circuit module, a switch circuit module and an MCU control circuit module. The DC boost module is connected to the first-stage triode voltage stabilizing circuit module, the second-stage triode voltage stabilizing circuit module and the switch circuit module are connected to the MCU control circuit module and the microphone input circuit module, and the microphone input circuit module is connected to the microphone amplifier circuit module and the gain switch module.

2. According to claim 1, a pre-stage input circuit system based on 48V phantom power supply and gain switch is characterized in that: The microphone amplifier circuit module is connected to the DSP circuit module.

3. A pre-stage input circuit system based on a 48V phantom power supply and a gain switch according to claim 2, characterized in that: The DSP circuit module is connected to the power amplifier circuit module.

4. The front-stage input circuit system based on 48V phantom power supply and gain switch according to claim 1, characterized in that: The DC boost module is connected to the second-stage triode voltage stabilizing circuit module and the switch circuit module.

5. The pre-stage input circuit system based on 48V phantom power supply and gain switch according to claim 1, characterized in that: The DC boost module is provided with an inductor L4 and a transformer U2. One end of the inductor L4 is connected to a 24V voltage, and the other end of the inductor L4 is connected to a second pin input end of the transformer U2. Resistors R6 and R7 are connected to D1.

6. A pre-stage input circuit system based on 48V phantom power supply and gain switch according to claim 5, characterized in that: The transformer U2 is connected to the DC-DC chip.

7. The pre-stage input circuit system based on 48V phantom power supply and gain switch according to claim 1, characterized in that: The second-stage triode voltage stabilizing circuit module is provided with a SW2 switch and an RC filter circuit, and the SW2 switch is connected to the RC filter circuit.

8. The pre-stage input circuit system based on 48V phantom power supply and gain switch according to claim 1, characterized in that: The microphone input circuit module is provided with a JK1 input terminal and a JK2 input terminal.

9. The front-stage input circuit system based on 48V phantom power supply and gain switch according to claim 8, characterized in that: The JK1 input terminal is connected to resistors R15, R16, inductors L2 and L3, the inductors L2 and L3 are connected to resistors R2 and R3, the JK2 input terminal is connected to inductor L1, and the inductor L1 is connected to resistor R17.

10. A pre-stage input circuit system based on 48V phantom power supply and gain switch according to claim 9, characterized in that: The resistor R17, the resistor R2 and the resistor R3 are connected to the 5th and 6th pins of the transformer U1.

Images