Static noise optimization circuit

Abstract

The static noise optimization circuit comprises a power amplifier chip, a first switching power supply, a second switching power supply, a first voltage stabilizing circuit, a filter circuit and audio output equipment, wherein the second switching power supply is used for being connected with audio input equipment; the first voltage stabilizing circuit is used for limiting amplitude and stabilizing voltage; the filter circuit is used for filtering high-frequency noise; an audio right channel line transmission signal of audio input equipment is transmitted to a right channel input pin of the power amplifier chip through one filter circuit, and an audio left channel line transmission signal of the audio input equipment is transmitted to a left channel input pin of the power amplifier chip through the other filter circuit. The ground wire of the first switching power supply and the audio ground wire of the audio input device are connected to the two ends of the first voltage stabilizing circuit, and the ground wire of the first switching power supply is connected to a ground pin of the power amplifier chip.

Description

Technical Field

[0001] The present application relates to the technical field of voltage stabilization and noise reduction, and more specifically, to a static noise optimization circuit. Background Art

[0002] Industrial equipment often uses multiple isolated switching power supplies for power supply. The GND voltage of each switching power supply is floating. Due to the existence of induced voltage, the voltage difference between GND and GND can be as high as 200V~300V. For example, Figure 1 The switching power supply circuit has a neutral line and a live line connected to the input end of the switching power supply circuit, and the output end of the switching power supply circuit can be connected to the audio input device and the power amplifier chip connected to the audio output device. When the industrial equipment uses two or more of the above-mentioned switching power supply circuits, a 200V~300V voltage difference will be generated between the GND and GND of the switching power supply. When the audio lines of the audio input device are connected to the power amplifier chip, at the least, a large noise will be generated when connected, and at worst, the power amplifier will be damaged when connected to the power amplifier chip. Summary of the invention

[0003] In view of the prior art, the technical problem solved by the present application is to provide a static noise optimization circuit for noise reduction and voltage stabilization.

[0004] In order to solve the above technical problems, the present application provides a static noise optimization circuit, which includes a power amplifier chip, a first switching power supply, a second switching power supply for connecting to an audio input device, a first voltage stabilizing circuit for limiting voltage stabilization, a filtering circuit for filtering high-frequency noise, and an audio output device connected to the channel power output amplification pin of the power amplifier chip; the audio right channel line transmission signal of the audio input device is transmitted to the right channel input pin of the power amplifier chip through one of the filtering circuits, and the audio left channel line transmission signal of the audio input device is transmitted to the left channel input pin of the power amplifier chip through another of the filtering circuits, the first switching power supply ground line and the audio ground line of the audio input device are connected to both ends of the first voltage stabilizing circuit, and the first switching power supply ground line is connected to the ground pin of the power amplifier chip.

[0005] In the static noise optimization circuit, when the voltage difference between the ground lines of the first switching power supply and the second switching power supply is large, the first regulated voltage can be used for voltage stabilization and limiting, and the high-frequency noise can be filtered through the filtering circuit, so that when the signal transmitted by the audio channel signal line is amplified by the power amplifier chip to the audio output device, excessive noise can be avoided and damage to the power amplifier chip can be avoided.

[0006] In some embodiments, the first voltage stabilizing circuit includes two diodes connected in reverse parallel, and the first switch power ground line and the audio ground line are respectively connected to two ends of the two diodes connected in reverse parallel.

[0007] In some embodiments, it is characterized in that the first voltage stabilizing circuit is a bidirectional voltage stabilizing tube, and the first switch power ground wire and the audio ground wire are respectively connected to two ends of the bidirectional voltage stabilizing tube.

[0008] In some embodiments, the filter circuit includes a first resistor, a first capacitor, a second resistor and a second capacitor; for the filter circuit connected to the audio left channel line, the first resistor and the first capacitor are connected in parallel and the two ends of the two are respectively connected to the audio left channel line and the first switch power ground line, one end of the second resistor is connected to the audio left channel line, the other end of the second resistor is connected to one end of the second capacitor, and the second capacitor is connected to the first switch power ground line; for the filter circuit connected to the audio right channel line, the first resistor and the first capacitor are connected in parallel and the two ends of the two are respectively connected to the audio right channel line and the first switch power ground line, one end of the second resistor is connected to the audio right channel line, the other end of the second resistor is connected to one end of the second capacitor, and the second capacitor is connected to the first switch power ground line.

[0009] In some embodiments, the filter circuit includes a capacitor group formed by two third capacitors connected in series, a resistor group formed by two third resistors connected in series, a fourth capacitor and a fourth resistor; for the filter circuit connected to the audio left channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio left channel line and the left channel input pin of the power amplifier chip, the two ends of the fourth resistor are respectively connected to the first switch power ground line and the series connection of the two third capacitors, and the two ends of the fourth capacitor are respectively connected to the first switch power ground line and the series connection of the two third resistors; for the filter circuit connected to the audio right channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio right channel line and the right channel input pin of the power amplifier chip, the two ends of the fourth resistor are respectively connected to the first switch power ground line and the series connection of the two third capacitors, and the two ends of the fourth capacitor are respectively connected to the first switch power ground line and the series connection of the two third resistors.

[0010] In some embodiments, the static noise optimization circuit further includes a second voltage stabilizing circuit for stabilizing the voltage of the first switching power supply, and the second voltage stabilizing circuit is connected to the first switching power supply and the power amplifier chip.

[0011] In some embodiments, the second voltage stabilizing circuit includes a first polarity capacitor, a second polarity capacitor, a third polarity capacitor, a first non-polarity capacitor, three diodes, a second non-polarity capacitor, a third non-polarity capacitor, a fourth non-polarity capacitor and a fifth non-polarity capacitor; the first polarity capacitor, the second polarity capacitor, the third polarity capacitor and the first non-polarity capacitor are connected in parallel to the positive output terminal and the ground of the first switching power supply; the anode and cathode of one of the diodes are respectively connected to the positive output terminal of the first switching power supply and the analog circuit power supply pin AVCC of the power amplifier chip, the anode and cathode of another diode are respectively connected to the positive output terminal of the first switching power supply and the right channel power supply pin PVCCR of the power amplifier chip, and the anode and cathode of another diode are respectively connected to the positive output terminal of the first switching power supply and the left channel power supply pin PVCCL of the power amplifier chip, the second non-polarity capacitor and the third non-polarity capacitor are connected in parallel and both ends are grounded and connected to the right channel power supply pin PVCCR, the fourth non-polarity capacitor and the fifth non-polarity capacitor are connected in parallel and both ends are grounded and connected to the left channel power supply pin PVCCL. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0013] Figure 1 A switching power supply circuit diagram in the prior art;

[0014] Figure 2 This is a principle block diagram of a static early warning circuit according to an embodiment of the present application;

[0015] Figure 3 A circuit diagram of a first voltage stabilizing circuit and a filtering circuit connected to a power amplifier chip according to an embodiment of the present application;

[0016] Figure 4 Another circuit diagram of a first voltage stabilizing circuit and a filtering circuit connected to a power amplifier chip according to an embodiment of the present application;

[0017] Figure 5 This is a circuit diagram of a second voltage stabilizing circuit connected to a power amplifier chip according to an embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0019] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0020] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0022] The static noise optimization circuit of the present application is now described in detail with reference to the accompanying drawings.

[0023] Please refer to Figure 2 The static noise optimization circuit 100 provided in the embodiment of the present application includes a power amplifier chip 10, a first switching power supply 20, a second switching power supply 40 for connecting to an audio input device 30, a first voltage stabilizing circuit 50 for limiting and stabilizing voltage, a filtering circuit 60 for filtering high-frequency noise, and an audio output device 70 connected to the channel power output amplification pin of the power amplifier chip 10.

[0024] The audio input device 30 may be, but not limited to, a computer, etc., and the audio output device 70 may be, but not limited to, headphones or speakers. The power amplifier chip 10 may be, but not limited to, PAM8610. The first switching power supply 20 and the second switching power supply 40 are used to provide voltage, and the circuit schematic diagram thereof is similar to Figure 1 same.

[0025] The audio right channel line transmission signal of the audio input device 30 is transmitted to the right channel input pin of the power amplifier chip 10 through a filter circuit 60. The audio left channel line transmission signal of the audio input device 30 is transmitted to the left channel input pin of the power amplifier chip 10 through another filter circuit 60. The ground line of the first switching power supply 20 and the audio ground line of the audio input device 30 are connected to both ends of the first voltage stabilizing circuit 50, and the ground line of the first switching power supply 20 is connected to the ground pin of the power amplifier chip 10.

[0026] In the static noise optimization circuit, when the voltage difference between the ground lines of the first switching power supply 20 and the second switching power supply 40 is large, the first regulated voltage can be used for voltage stabilization and limiting, and the high-frequency noise is filtered through the filter circuit 60, so that when the signal transmitted by the audio channel signal line is amplified by the power amplifier chip 10 to the audio output device 70, excessive noise is avoided and damage to the power amplifier chip 10 is avoided.

[0027] In a specific embodiment, if Figure 3 As shown, the first voltage stabilizing circuit 50 includes two diodes connected in reverse parallel, and the ground wire of the first switching power supply 20 and the audio ground wire are respectively connected to the two ends of the two diodes connected in reverse parallel. It can be understood that the voltage between the ground wire of the first switching power supply 20 and the audio ground wire is stabilized and limited by using the two diodes connected in reverse parallel, so that the voltage between the two is limited to a fixed amplitude range. For example, according to the selection of the diode, the voltage between the audio ground wire and the ground wire of the first switching power supply 20 can be limited to within plus or minus 0.7.

[0028] In another specific embodiment, the first voltage regulator circuit 50 is a bidirectional voltage regulator tube, and the ground wire of the first switching power supply 20 and the audio ground wire are respectively connected to the two ends of the bidirectional voltage regulator tube. The function of the bidirectional voltage regulator tube is the same as that of the two reverse parallel diodes in the previous embodiment.

[0029] In a specific embodiment, if Figure 3As shown, the filter circuit 60 includes a first resistor 61, a first capacitor 62, a second resistor 63 and a second capacitor 64. In the filter circuit 60 connected to the audio left channel line, the first resistor 61 and the first capacitor 62 are connected in parallel and both ends are connected to the audio left channel line and the ground line of the first switch power supply 20, one end of the second resistor 63 is connected to the audio left channel line, the other end of the second resistor 63 is connected to one end of the second capacitor 64, and the second capacitor 64 is connected to the ground line of the first switch power supply 20. In the filter circuit 60 connected to the audio right channel line, the first resistor 61 and the first capacitor 62 are connected in parallel and both ends are connected to the audio right channel line and the ground line of the first switch power supply 20, one end of the second resistor 63 is connected to the audio right channel line, the other end of the second resistor 63 is connected to one end of the second capacitor 64, and the second capacitor 64 is connected to the ground line of the first switch power supply 20.

[0030] It is worth noting that, in this example, the filter circuit 60 forms a π-shaped filter circuit 60. The audio left channel line transmission signal in the audio line of the audio input device 30 needs to be transmitted to the power amplifier chip 10 for amplification through the π-shaped filter circuit, and then output through the audio output device 70. Similarly, the audio right channel line transmission signal in the audio line of the audio input device 30 needs to be transmitted to the power amplifier chip 10 for amplification through the π-shaped filter circuit, and then output through the audio output device 70.

[0031] In another specific embodiment, Figure 4 As shown, the filter circuit 60 includes a capacitor group formed by two third capacitors 65 connected in series, a resistor group formed by two third resistors 66 connected in series, a fourth capacitor 67 and a fourth resistor 68. In the filter circuit 60 connected to the audio left channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio left channel line and the left channel input pin of the power amplifier chip 10, the two ends of the fourth resistor 68 are respectively connected to the ground line of the first switching power supply 20 and the serial connection of the two third capacitors 65, and the two ends of the fourth capacitor 67 are respectively connected to the ground line of the first switching power supply 20 and the serial connection of the two third resistors 66. Among them, for the filter circuit 60 connected to the audio right channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio right channel line and the right channel input pin of the power amplifier chip 10, the two ends of the fourth resistor 68 are respectively connected to the ground wire of the first switching power supply 20 and the series connection of the two third capacitors 65, and the two ends of the fourth capacitor 67 are respectively connected to the ground wire of the first switching power supply 20 and the series connection of the two third resistors 66.

[0032] It is worth noting that, in this example, the filter circuit 60 forms a T filter circuit. The audio left channel line transmission signal in the audio line of the audio input device 30 needs to be transmitted to the power amplifier chip 10 through the T filter circuit 60 circuit for amplification, and then output through the audio output device 70. Similarly, the audio right channel line transmission signal in the audio line of the audio input device 30 needs to be transmitted to the power amplifier chip 10 through the T filter circuit 60 circuit for amplification, and then output through the audio output device 70.

[0033] Furthermore, in the above embodiment, the static noise optimization circuit 100 further includes a second voltage stabilizing circuit for stabilizing the voltage of the first switching power supply 20 , and the second voltage stabilizing circuit is connected to the first switching power supply 20 and the power amplifier chip 10 .

[0034] Specifically, the second voltage stabilizing circuit includes a first polarity capacitor C1, a second polarity capacitor C53, a third polarity capacitor C2, a first non-polarity capacitor C42, three diodes, a second non-polarity capacitor 49, a third non-polarity capacitor 50, a fourth non-polarity capacitor 51 and a fifth non-polarity capacitor 52. The first polarity capacitor C1, the second polarity capacitor C53, the third polarity capacitor C2 and the first non-polarity capacitor C42 are connected in parallel to the positive output terminal of the first switching power supply 20 and the ground line of the first switching power supply 20. The anode and cathode of one diode D1 are respectively connected to the positive output terminal of the first switching power supply 20 and the analog circuit power supply pin AVCC of the power amplifier chip 10; the anode and cathode of another diode D2 are respectively connected to the positive output terminal of the first switching power supply 20 and the right channel power supply pin PVCCR of the power amplifier chip 10, and the anode and cathode of another diode D3 are respectively connected to the positive output terminal of the first switching power supply 20 and the left channel power supply pin PVCCL of the power amplifier chip 10. The second non-polar capacitor 49 and the third non-polar capacitor 50 are connected in parallel, and both ends are grounded and connected to the right channel power supply pin PVCCR, respectively. The fourth non-polar capacitor 51 and the fifth non-polar capacitor 52 are connected in parallel, and both ends are grounded and connected to the left channel power supply pin PVCCL.

[0035] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A static noise optimization circuit, characterized in that: It includes a power amplifier chip, a first switching power supply, a second switching power supply connected to an audio input device, a first voltage stabilizing circuit for limiting voltage stabilization, a filtering circuit for filtering high-frequency noise, and an audio output device connected to the channel power output amplification pin of the power amplifier chip; the audio right channel line transmission signal of the audio input device is transmitted to the right channel input pin of the power amplifier chip through the filtering circuit, the audio left channel line transmission signal of the audio input device is transmitted to the left channel input pin of the power amplifier chip through the filtering circuit, the first switching power supply ground line and the audio ground line of the audio input device are connected to both ends of the first voltage stabilizing circuit, and the first switching power supply ground line is connected to the ground pin of the power amplifier chip.

2. The static noise optimization circuit according to claim 1, characterized in that: The first voltage stabilizing circuit includes two diodes connected in reverse parallel, and the first switch power ground wire and the audio ground wire are respectively connected to two ends of the two diodes connected in reverse parallel.

3. The static noise optimization circuit according to claim 1, characterized in that: The first voltage stabilizing circuit is a bidirectional voltage stabilizing tube, and the first switch power ground wire and the audio ground wire are respectively connected to two ends of the bidirectional voltage stabilizing tube.

4. The static noise optimization circuit according to claim 1, characterized in that: The filter circuit includes a first resistor, a first capacitor, a second resistor and a second capacitor; for the filter circuit connected to the audio left channel line, the first resistor and the first capacitor are connected in parallel and both ends are connected to the audio left channel line and the first switch power ground line respectively, one end of the second resistor is connected to the audio left channel line, the other end of the second resistor is connected to one end of the second capacitor, and the second capacitor is connected to the first switch power ground line; for the filter circuit connected to the audio right channel line, the first resistor and the first capacitor are connected in parallel and both ends are connected to the audio right channel line and the first switch power ground line respectively, one end of the second resistor is connected to the audio right channel line, the other end of the second resistor is connected to one end of the second capacitor, and the second capacitor is connected to the first switch power ground line.

5. The static noise optimization circuit according to claim 1, characterized in that: The filter circuit includes a capacitor group formed by two third capacitors connected in series, a resistor group formed by two third resistors connected in series, a fourth capacitor and a fourth resistor; for the filter circuit connected to the audio left channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio left channel line and the left channel input pin of the power amplifier chip, the two ends of the fourth resistor are respectively connected to the first switch power ground line and the series connection of the two third capacitors, and the two ends of the fourth capacitor are respectively connected to the first switch power ground line and the series connection of the two third resistors; for the filter circuit connected to the audio right channel line, the capacitor group and the resistor group are connected in parallel and the two ends of the capacitor group are respectively connected to the audio right channel line and the right channel input pin of the power amplifier chip, the two ends of the fourth resistor are respectively connected to the first switch power ground line and the series connection of the two third capacitors, and the two ends of the fourth capacitor are respectively connected to the first switch power ground line and the series connection of the two third resistors.

6. The static noise optimization circuit according to any one of claims 1 to 5, characterized in that: The static noise optimization circuit also includes a second voltage stabilizing circuit for stabilizing the voltage of the first switching power supply, and the second voltage stabilizing circuit is connected to the first switching power supply and the power amplifier chip.

7. The static noise optimization circuit according to claim 6, characterized in that: The second voltage stabilizing circuit includes a first polarity capacitor, a second polarity capacitor, a third polarity capacitor, a first non-polarity capacitor, three diodes, a second non-polarity capacitor, a third non-polarity capacitor, a fourth non-polarity capacitor and a fifth non-polarity capacitor; the first polarity capacitor, the second polarity capacitor, the third polarity capacitor and the first non-polarity capacitor are connected in parallel to the two ends of the first switching power supply; the anode and cathode of one of the diodes are respectively connected to the positive output end of the first switching power supply and the analog circuit power supply pin AVCC of the power amplifier chip, the anode and cathode of another diode are respectively connected to the positive output end of the first switching power supply and the right channel power supply pin PVCCR of the power amplifier chip, and the anode and cathode of another diode are respectively connected to the positive output end of the first switching power supply and the left channel power supply pin PVCCL of the power amplifier chip, the second non-polarity capacitor and the third non-polarity capacitor are connected in parallel, and the two ends are respectively grounded and connected to the right channel power supply pin PVCCR, and the fourth non-polarity capacitor is connected in parallel, and the two ends are respectively grounded and connected to the left channel power supply pin PVCCL.

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