CN108200518B - Audio circuit and audio equipment for eliminating instant noise during power-on - Google Patents
Audio circuit and audio equipment for eliminating instant noise during power-on Download PDFInfo
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- CN108200518B CN108200518B CN201810184296.5A CN201810184296A CN108200518B CN 108200518 B CN108200518 B CN 108200518B CN 201810184296 A CN201810184296 A CN 201810184296A CN 108200518 B CN108200518 B CN 108200518B
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- 230000001052 transient effect Effects 0.000 claims abstract description 8
- 239000003990 capacitor Substances 0.000 claims description 29
- 230000005236 sound signal Effects 0.000 claims description 9
- 238000001514 detection method Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 4
- 238000001914 filtration Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/12—Circuits for transducers, loudspeakers or microphones for distributing signals to two or more loudspeakers
Abstract
An audio circuit for eliminating the transient noise of power-on comprises an audio socket with a left channel terminal, a right channel terminal and a ground terminal, two switch modules respectively connected with the left channel terminal and the right channel terminal of the audio socket, two audio input modules respectively correspondingly connected with the two switch modules, two audio output modules respectively correspondingly connected with the two switch modules, a main control module connected with a working power supply and the two switch modules and also connected with the left channel terminal or the right channel terminal. Through detecting the power-on voltage signal of the audio socket, the switch module is controlled by software to drive the switch module to be conducted after the power-on voltage is stable, so that noise at the moment of power-on of audio equipment is effectively eliminated, the sound quality effect is improved, the audio input and output are optional, and the audio input and output share one audio socket.
Description
Technical Field
The invention belongs to the technical field of audio circuits, and particularly relates to an audio circuit and audio equipment for eliminating instant noise during power-on.
Background
At present, the display device can be provided with audio output, so that the earphone or the sound equipment can be conveniently connected, however, the power supply voltage of the power supply end of the audio output can be changed severely at the moment of power-on or power-on signal, so that the audio output on the display device can emit pop noise at the moment of power-on, and the tone quality effect is affected.
Therefore, in the conventional technical scheme, the problem that the audio output on the display device emits pop noise at the moment of power-on exists.
Disclosure of Invention
The invention provides an audio circuit for eliminating noise at the moment of power-on, and aims to solve the problem that the audio output of audio equipment in the traditional technical scheme gives out pop noise at the moment of power-on.
The invention is realized in such a way that an audio circuit for eliminating the noise at the moment of power-on comprises:
an audio jack having a left channel terminal, a right channel terminal, and a ground terminal;
the two switch modules are respectively connected with the left channel terminal and the right channel terminal of the audio socket and are used for controlling the input and output of audio signals;
the two audio input modules are respectively and correspondingly connected with the two switch modules and are used for inputting audio signals;
the two audio output modules are respectively and correspondingly connected with the two switch modules and are used for outputting audio signals;
and the main control module is connected with the working power supply and the two switch modules, is also connected with the left channel terminal or the right channel terminal, detects the power-on voltage signal of the left channel terminal or the right channel terminal and controls the on-off of the two switch modules according to the power-on voltage signal.
In addition, an audio device is provided, which comprises the audio circuit for eliminating the instant noise during power-on.
The audio circuit for eliminating the transient noise of the electrification can detect the electrification voltage value of the left channel terminal or the right channel terminal of the audio socket through the main control module, can control the on-off of the two switch modules according to the electrification voltage value, can disconnect the switch modules in the electrification moment, and avoids the explosion noise caused by the severe change of the power supply voltage in the electrification moment, thereby affecting the tone quality effect and realizing the purpose of eliminating the transient noise of the electrification of the audio equipment. In addition, the scheme can eliminate noise generated by the audio equipment at the moment of power-on, improve the tone quality effect, and realize the optional audio input and output.
Drawings
Fig. 1 is a schematic diagram of an audio circuit module for eliminating transient noise during power-on according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an audio circuit for eliminating transient noise during power-up according to an embodiment of the present invention;
fig. 3 is a schematic diagram of an audio circuit for eliminating noise at the instant of power-up according to another embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Fig. 1 is a schematic diagram of an audio circuit module for eliminating instant noise during power-on according to a preferred embodiment of the present invention, and for convenience of explanation, only the portions related to the present embodiment are shown, which are described in detail below:
referring to fig. 1, an audio circuit for eliminating power-on transient noise, comprising: two switch modules (11, 12), an audio jack 20, a main control module 30, two audio input modules (41, 42), and two audio output modules (51, 52).
Wherein the audio jack 20 has left channel terminals (1, 2), right channel terminals (3, 4) and a ground terminal 5; the two switch modules (11, 12) are respectively connected with the left channel terminals (1, 2) and the right channel terminals (3, 4) of the audio socket 20 and are used for controlling audio signal input and output; the two audio input modules (41, 42) are respectively and correspondingly connected with the two switch modules (11, 12) and are used for inputting audio signals; the two audio output modules (51, 52) are respectively and correspondingly connected with the two switch modules (11, 12) and are used for outputting audio signals; the main control module 30 is connected with a working power supply and two switch modules (11, 12), is also connected with left channel terminals (1, 2) or right channel terminals (3, 4), detects power-on voltage signals of the left channel terminals (1, 2) or the right channel terminals (3, 4) and controls the on-off of the two switch modules (11, 12) according to the power-on voltage signals.
In one embodiment, referring to fig. 2, taking one of the switch modules 11 as an example, the switch module 11 includes a first switch chip Q1, an output end of the first switch chip Q1 is connected to the left channel terminals (1, 2) of the audio jack 20, an input end of the first switch chip Q1 is connected to an input end of one of the audio input modules 41 and an output end of one of the audio output modules 51, and a control end of the first switch chip Q1 is connected to a driving end of the main control module 30. The above description has been made taking the switch module 11 provided on the left channel input/output channel of the left channel terminal 1 as an example, and the other switch module 12 on the right channel input/output channel of the right channel terminal 4 is the same as the switch module 10 on the left channel input/output channel except that it is connected to the right channel terminals (3, 4). Specifically, the other switch module 12 includes a third switch chip Q3, an output end of the third switch chip Q3 is connected to the right channel terminals (3, 4) of the audio jack 20, an input end of the third switch chip Q3 is connected to an input end of the other audio input module 42 and an output end of the other audio output module 52, and a control end of the third switch chip Q3 is connected to the driving end of the main control module 30.
Referring to fig. 2 or 3, the main control module 30 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a third capacitor C3, a triode Q5, and a main control chip (not shown), wherein the first end of the third resistor R3 and the first end of the fifth resistor R5 are connected to the positive end of the working power supply, the second end of the third resistor R3, the collector of the triode Q5, and the first end of the third capacitor C3 are commonly connected to the driving end of the main control module 30 and to the switch module 10, the emitter of the triode Q5 is commonly grounded to the second end of the third capacitor C3, the base of the triode Q5 is connected to the first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected to the driving pin of the main control chip, the second end of the fifth resistor R5 and the first end of the sixth resistor R6 are commonly connected to the left channel terminal 2 or the right channel terminal (3, 4) of the audio jack 20, and the second end of the sixth resistor R6 is connected to the detection pin of the main control chip. The operating power may be 5V.
As described above, when the audio jack is connected to the earphone, the main control module 30 detects the power-on voltage of the left channel terminal (1, 2) or the right channel terminal (3, 4), and when the power-on voltage is the audio output voltage, the first switch chip Q1 connected to the left channel terminal (1, 2) and the third switch chip Q3 connected to the right channel terminal (3, 4) are controlled to be turned on or off by the switch of the triode Q5. Because the voltage of the audio socket at the moment of power-on changes drastically to make the audio output emit the pop noise at the moment of power-on, the first switch chip Q1 and the third switch chip Q3 can be controlled to be turned on in a delayed manner by the main control module 30, and after the power-on voltage is stable, the first switch chip Q1 is driven to be turned on.
In a further embodiment, referring to fig. 3, taking one of the switch modules 11 as an example, the switch module 11 further includes a second switch chip Q2, the output end of the first switch chip Q1 is connected to the output end of the second switch chip Q2, the input end of the second switch chip Q2 is connected to the left channel terminals (1, 2) of the audio jack 20, and the control end of the second switch chip Q2 and the control end of the first switch chip Q1 are commonly connected to the driving end of the main control module 30. The other switch module 12 further includes a fourth switch chip Q4, where an output end of the fourth switch chip Q4 is connected to an output end of the third switch chip Q3, an input end of the fourth switch chip Q4 is connected to right channel terminals (3, 4) of the audio jack 20, and a control end of the fourth switch chip Q4 and a control end of the third switch chip Q3 are connected to a driving end of the main control module 30. In this embodiment, the first switch chip Q1, the second switch chip Q2, the third switch chip Q3, and the fourth switch chip Q4 adopt a symmetrical design and a differential wiring to perform wiring, so that differential mode crosstalk is eliminated, and an audio input and output are optional, and share one audio jack.
It should be noted that, the first switch chip Q1, the second switch chip Q2, the third switch chip Q3, and the fourth switch chip Q4 are all N-type MOS transistors, and the input end, the output end, and the control end of the first switch chip Q1, the second switch chip Q2, the third switch chip Q3, and the fourth switch chip Q4 are respectively the drain electrode, the source electrode, and the gate electrode of the MOS transistors.
Referring to fig. 2 or 3, taking one audio input module 41 as an example, the audio input module 41 includes a first resistor R1 and a first capacitor C1, where a first end of the first resistor R1 and a first end of the first capacitor C1 are commonly connected as an input end of the audio input module 41 and are connected to the switch module 11 (specifically, an input end of the first switch chip Q1), a second end of the first capacitor C1 is used as an output end of the audio input module 41, and a second end of the first resistor R1 is grounded. The above description has been made taking the audio input module 41 provided on the left channel output/input channel of the left channel terminal 1 as an example, and the other audio input module 42 on the right channel output/input channel is the same as the audio input module 41 on the left channel output/input channel except that it is connected to the switch module 12. Specifically, the other audio input module 42 includes a tenth resistor R10 and a sixth capacitor C6, where a first end of the tenth resistor R10 and a first end of the sixth capacitor C6 are commonly connected as an input end of the audio input module 42 and are connected to the switch module 12 (specifically, an input end of the third switch chip Q3), a second end of the sixth capacitor C6 is used as an output end of the audio input module 42, and a second end of the tenth resistor R10 is grounded.
Referring to fig. 2 or 3, taking one audio output module 51 as an example, the audio output module 51 includes a second resistor R2 and a second capacitor C2, wherein a first end of the second resistor R2 is used as an output end of the audio output module 51 and is connected to the switch module 11 (specifically, an input end of the first switch chip Q1), a second end of the second resistor R2 is connected to a first end of the second capacitor C2, and a second end of the second capacitor C2 is used as an input end of the audio output module 51. The above description has been made taking the audio output module 51 provided on the left channel output/input channel of the left channel terminal 1 as an example, and the other audio output module 52 on the right channel output/input channel is the same as the audio output module 51 on the left channel output/input channel except that it is connected to the switch module 12. Specifically, the other audio output module 52 includes an eleventh resistor R11 and a seventh capacitor C7, where a first end of the eleventh resistor R11 is used as an output end of the audio output module 52 and is connected to the switch module 12 (specifically, an input end of the third switch chip Q3), a second end of the eleventh resistor R11 is connected to a first end of the seventh capacitor C7, and a second end of the seventh capacitor C7 is used as an input end of the audio output module 52.
Referring to fig. 2 or 3, the audio circuit for eliminating the instant noise of power-on further includes a filtering module 60, the filtering module 60 is connected between the audio jack 20 and the switching module (11, 12), and the filtering module 60 performs filtering processing on the input or output audio information. The filtering module 60 includes a fourth capacitor C4, a fifth capacitor C5, an eighth resistor R8, and a ninth resistor R9, where a first end of the fourth resistor R4, a first end of the fifth capacitor C5, a first end of the eighth resistor R8, and a first end of the ninth resistor R9 are commonly grounded, a second end of the fourth capacitor C4 and a second end of the eighth resistor R8 are both connected to left channel terminals (1, 2) of the audio jack 20, and a second end of the fifth capacitor C5 and a second end of the ninth resistor R9 are both connected to right channel terminals (3, 4) of the audio jack 20.
With reference to fig. 1, 2 or 3, the two switch modules (11, 12), the two audio input modules (41, 42) and the two audio output modules (51, 52) are symmetrically connected.
In addition, an audio device is provided, and the audio device comprises the audio circuit for eliminating the instant noise during power-on.
The invention has the beneficial effects that:
(1) The switch modules (Q1, Q2, Q3 and Q4) and the main control module are added, and the main control module controls the switch modules through software to drive the switch modules to be conducted after the power-on voltage is stable, so that noise at the power-on moment is effectively eliminated.
(2) Q1, Q2, Q3 and Q4 adopt symmetrical design and differential wiring, eliminate differential mode crosstalk, and give consideration to the fact that audio input and output are optional, and can share one audio jack.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (5)
1. An audio circuit for removing transient noise during power-up, the audio circuit comprising:
an audio jack having a left channel terminal, a right channel terminal, and a ground terminal;
the two switch modules are respectively connected with the left channel terminal and the right channel terminal of the audio socket and are used for controlling the input and output of audio signals;
the two audio input modules are respectively and correspondingly connected with the two switch modules and are used for inputting audio signals;
the two audio output modules are respectively and correspondingly connected with the two switch modules and are used for outputting audio signals;
the main control module is connected with the working power supply and the two switch modules, is also connected with the left channel terminal or the right channel terminal, detects a power-on voltage signal of the left channel terminal or the right channel terminal and controls the on-off of the two switch modules according to the power-on voltage signal;
the audio socket comprises an audio input module, an audio output module, a main control module and a switch module, wherein the switch module comprises a first switch chip, the output end of the first switch chip is connected with the left channel terminal of the audio socket, the input end of the first switch chip is connected with the input end of the audio input module and the output end of the audio output module, and the control end of the first switch chip is connected with the driving end of the main control module;
the switch module further comprises a second switch chip, the output end of the first switch chip is commonly connected with the output end of the second switch chip, the input end of the second switch chip is connected with the left sound channel terminal of the audio socket, and the control end of the second switch chip and the control end of the first switch chip are commonly connected to the driving end of the main control module;
the first switch chip and the second switch chip are N-type MOS transistors, and the input end, the output end and the control end of the first switch chip and the second switch chip are drain electrodes, source electrodes and grid electrodes of the MOS transistors respectively;
the main control module comprises a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a third capacitor, a triode and a main control chip, wherein the first end of the third resistor and the first end of the fifth resistor are connected with the positive end of a working power supply, the second end of the third resistor, the collector of the triode and the first end of the third capacitor are commonly connected to serve as the driving end of the main control module and are connected with a switch module, the emitting electrode of the triode and the second end of the third capacitor are commonly grounded, the base electrode of the triode is connected with the first end of the fourth resistor, the second end of the fourth resistor is connected with a driving pin of the main control chip, the second end of the fifth resistor and the first end of the sixth resistor are commonly connected to a left sound channel terminal or a right sound channel terminal of an audio socket, and the second end of the sixth resistor is connected with a detection pin of the main control chip.
2. The audio circuit for eliminating instant noise of power-on as defined in claim 1, wherein the audio input module comprises a first resistor and a first capacitor, a first end of the first resistor and a first end of the first capacitor are commonly connected as an input end of the audio input module and are connected with the switch module, a second end of the first capacitor is used as an output end of the audio input module, and a second end of the first resistor is grounded.
3. The audio circuit of claim 1, wherein the audio output module comprises a second resistor and a second capacitor, a first end of the second resistor being an output end of the audio output module and being connected to the switch module, a second end of the second resistor being connected to a first end of the second capacitor, and a second end of the second capacitor being an input end of the audio output module.
4. The audio circuit for eliminating instant noise of power-on as defined in claim 1, wherein the two switch modules, the two audio input modules and the two audio output modules are symmetrically connected.
5. An audio device comprising an audio circuit for removing transient noise from power up as claimed in any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810184296.5A CN108200518B (en) | 2018-03-07 | 2018-03-07 | Audio circuit and audio equipment for eliminating instant noise during power-on |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810184296.5A CN108200518B (en) | 2018-03-07 | 2018-03-07 | Audio circuit and audio equipment for eliminating instant noise during power-on |
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| Publication Number | Publication Date |
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| CN108200518A CN108200518A (en) | 2018-06-22 |
| CN108200518B true CN108200518B (en) | 2024-04-12 |
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| CN201810184296.5A Active CN108200518B (en) | 2018-03-07 | 2018-03-07 | Audio circuit and audio equipment for eliminating instant noise during power-on |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI768466B (en) * | 2020-09-10 | 2022-06-21 | 美律實業股份有限公司 | Playback device and control method |
| CN113115180B (en) * | 2021-04-28 | 2022-08-02 | 广州朗国电子科技股份有限公司 | Plosive removing device of audio output end and audio equipment |
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| CN108200518A (en) | 2018-06-22 |
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