CN110719547A - Audio circuit assembly - Google Patents

Abstract

An audio circuit assembly includes an audio connector, a signal processing unit, a first filtering unit and an electrostatic protection unit. The audio connector is used for plugging with peripheral audio equipment. The signal processing unit is electrically connected to the audio connector for outputting a first audio signal to the audio connector or receiving a second audio signal input from the audio connector. The first filtering unit is electrically connected between the signal processing unit and the audio connector, and is used for filtering out the noise signal contained in the first audio signal or the second audio signal. The electrostatic protection unit is electrically connected to the common terminal of the first filter unit and the audio connector, and is used for electrostatic protection of the signal processing unit and the first filter unit. The above audio circuit components can effectively avoid noise interference and electrostatic damage.

Description

audio circuit components

technical field

The present invention relates to the technical field of electronic equipment, and in particular, to an audio circuit assembly with electrostatic protection function.

Background technique

With the rapid development of modern electronic technology and integrated circuits, electronic equipment has become increasingly miniaturized, multi-functional and intelligent. Various electronic products have audio playback functions, such as mobile phones, portable multimedia players, laptops, desktops, radios, etc. These electronic products are generally equipped with headphone jacks, so it is easy to become a gateway for static electricity to enter the whole machine. It is necessary to reduce the harm of ESD (Electro Static Discharge) to ensure the high audio quality of the electronic equipment.

SUMMARY OF THE INVENTION

In view of the above, it is necessary to provide an audio circuit assembly that can effectively eliminate ESD hazards.

An embodiment of the present invention provides an audio circuit assembly, including an audio connector, and the audio connector is used for plugging with a peripheral audio device. The audio circuit assembly further includes: a signal processing unit electrically connected to the audio connector for outputting a first audio signal to the audio connector or receiving a second audio signal input by the audio connector; a first audio signal a filtering unit, electrically connected between the signal processing unit and the audio connector, for filtering out the noise signal contained in the first audio signal or the second audio signal; and an electrostatic protection unit, electrically connected The common end of the first filter unit and the audio connector is used for electrostatic protection for the signal processing unit and the first filter unit.

Preferably, the signal processing unit includes an audio processing chip, and the audio processing chip includes a left channel signal pin and a right channel signal pin, and the left channel signal pin and the right channel signal pin are respectively is electrically connected to the first filtering unit.

Preferably, the first filter unit includes: a first capacitor, one end of which is electrically connected to the left channel signal pin; a first resistor, one end of which is electrically connected to the other end of the first capacitor, and the other end is electrically connected to The left channel pin of the audio connector; a second capacitor, one end is electrically connected to the right channel signal pin; and a second resistor, one end is electrically connected to the other end of the second capacitor, and the other end is electrically connected Connect to the right channel pin of the audio connector.

Preferably, the first filter unit further includes a first magnetic bead and a second magnetic bead, the first magnetic bead is electrically connected between the first resistor and the left channel pin, and the second magnetic bead is electrically connected between the first resistor and the left channel pin. The magnetic bead is electrically connected between the second resistor and the right channel pin.

Preferably, the electrostatic protection unit comprises: a first TVS tube, one end of which is electrically connected to the common end of the first resistor and the audio connector, and the other end is grounded; and a second TVS tube, one end of which is electrically connected to the The second resistor is connected to the common end of the audio connector, and the other end is grounded.

Preferably, it further includes a second filter unit, the second filter unit includes a third capacitor and a fourth capacitor, and one end of the third capacitor is electrically connected to the common end of the first TVS transistor and the first resistor , the other end of the third capacitor is grounded, one end of the fourth capacitor is electrically connected to the common terminal of the second TVS tube and the second resistor, and the other end of the fourth capacitor is grounded.

Preferably, the capacitance value of the third capacitor is much smaller than the capacitance value of the first capacitor, and the capacitance value of the fourth capacitor is much smaller than the capacitance value of the second capacitor.

Preferably, the electrostatic protection unit includes: a first voltage regulator tube, the negative electrode of which is electrically connected to the common terminal of the first resistor and the audio connector; a third resistor, one end of which is electrically connected to the first voltage regulator tube The positive electrode of the second voltage regulator tube is connected to the common terminal of the second resistor and the audio connector; and the fourth resistor is electrically connected to the positive electrode of the second voltage regulator tube at one end. , and the other end is grounded.

Compared with the prior art, the above audio circuit assembly can effectively avoid noise interference and electrostatic damage, improve the sound quality and stability of audio products, and have low cost.

Description of drawings

FIG. 1 is an operating environment diagram of an embodiment of the audio circuit assembly of the present invention.

FIG. 2 is a functional block diagram of an embodiment of an audio circuit assembly of the present invention.

3 is a circuit diagram of one embodiment of an audio circuit assembly of the present invention.

Figure 4 is a circuit diagram of another embodiment of the audio circuit assembly of the present invention.

Description of main component symbols

audio connector 10 signal processing unit 20 first filter unit 30 ESD protection unit 40 second filter unit 50 audio circuit components 100 Electronic equipment 200 Peripheral audio equipment 300 1st to 4th capacitors C1, C2, C3, C4 1st to 4th resistors R1, R2, R3, R4 The first to second magnetic beads FB1, FB2 1st to 2nd TVS tube D11, D12 The first to the second Zener tube D21, D22 Left channel pin LP1 Right channel pin RP1 ground pin GND audio processing chip U1 Left channel signal pin LL1 Right channel signal pin LR1

Detailed ways

The following specific embodiments will further illustrate the present invention in conjunction with the above drawings.

Referring to FIGS. 1-2, an embodiment of the present invention provides an audio circuit assembly 100, which can be used in an electronic device 200, and the electronic device 200 can be a mobile phone, a computer, a portable multimedia player, or other device with an audio playback function .

The audio circuit assembly 100 includes an audio connector 10 , a signal processing unit 20 , a first filtering unit 30 and an electrostatic protection unit 40 . The audio connector 10 is used for plugging with the peripheral audio device 300 .

In one embodiment, the audio connector 10 is preferably an earphone interface, such as a 3.5mm standard earphone interface, a 2.5mm standard earphone interface, a Lightning Dock interface, and the like. The peripheral audio device 300 may be a device such as an earphone, a microphone, and a speaker.

The signal processing unit 20 is electrically connected to the audio connector 10 , and the signal processing unit 20 is configured to output a first audio signal to the audio connector 10 or receive a second audio signal input from the audio connector 10 .

In one embodiment, the signal processing unit 20 preferably includes an audio processing chip, and the audio processing chip can process the first audio signal and the second audio signal.

The first filtering unit 30 is electrically connected between the signal processing unit 20 and the audio connector 10, and the first filtering unit 30 is used for filtering the first audio signal or the second audio signal noise signal contained in . The noise signal may include audio noise, electromagnetic interference noise, spike noise, and the like.

The electrostatic protection unit 40 is electrically connected to the common terminal of the first filter unit 30 and the audio connector 10 , and the electrostatic protection unit 40 is used for protecting the signal processing unit 20 and the first filter unit 30 Perform electrostatic protection. The electrostatic protection unit 40 can absorb electrostatic pulses to implement electrostatic protection for the electronic components at the back end.

In one embodiment, the audio circuit assembly 100 further includes a second filter unit 50, and the second filter unit 50 is electrically connected to the common terminal of the first filter unit 30 and the electrostatic protection unit 40 for The interference signal contained in the first audio signal or the second audio signal is further filtered, so as to improve the high audio quality of the electronic device 200 .

Please also refer to FIG. 3 , which is a circuit diagram of an audio circuit assembly 100 according to an embodiment of the present invention.

The audio connector 10 includes a left channel pin LP1, a right channel pin RP1 and a ground pin GND. The ground pin GND is grounded. The signal processing unit 20 includes an audio processing chip U1, the audio processing chip U1 includes a left channel signal pin LL1 and a right channel signal pin LR1, and the left channel signal pin LL1 is used to process the left channel. Audio signal, the right channel signal pin LR1 is used to process the right channel audio signal. The first filter unit 30 includes a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a first magnetic bead FB1 and a second magnetic bead FB2. One end of the first capacitor C1 is electrically connected to the left channel signal pin LL1 of the audio processing chip U1, the other end of the first capacitor C1 is electrically connected to one end of the first resistor R1, and the first The other end of a resistor R1 is electrically connected to one end of the first magnetic bead FB1 , and the other end of the first magnetic bead FB1 is electrically connected to the left channel pin LP1 of the audio connector 10 . One end of the second capacitor C2 is electrically connected to the right channel signal pin LR1 of the audio processing chip U1, the other end of the second capacitor C2 is electrically connected to one end of the second resistor R2, and the first The other end of the two resistors R2 is electrically connected to one end of the second magnetic bead FB2 , and the other end of the second magnetic bead FB2 is electrically connected to the right channel pin RP1 of the audio connector 10 .

The second filter unit 50 includes a third capacitor C3 and a fourth capacitor C4. One end of the third capacitor C3 is electrically connected to the common end of the first magnetic bead FB1 and the left channel pin LP1, and the other end of the third capacitor C3 is grounded. One end of the fourth capacitor C4 is electrically connected to the common end of the second magnetic bead FB2 and the right channel pin RP1, and the other end of the fourth capacitor C4 is grounded.

In one embodiment, the capacitance value of the third capacitor C3 is much smaller than the capacitance value of the first capacitor C1, and the capacitance value of the fourth capacitor C4 is much smaller than the capacitance value of the second capacitor C2. The capacitance value of the first capacitor C1 is preferably 22uF, and the capacitance value of the third capacitor C3 is preferably 470PF. The capacitance value of the second capacitor C2 is preferably 22uF, and the capacitance value of the fourth capacitor C4 is preferably 470PF.

In one embodiment, the electrostatic protection unit 40 includes a first TVS tube D11 and a second TVS tube D12. One end of the first TVS tube D11 is electrically connected to the common terminal of the third capacitor C3 and the left channel pin LP1, and the other end of the first TVS tube D11 is grounded. One end of the second TVS tube D12 is electrically connected to the common terminal of the fourth capacitor C4 and the right channel pin RP1, and the other end of the second TVS tube D12 is grounded. When an electrostatic high-voltage pulse flows into the audio connector 10, an avalanche occurs in the first TVS transistor D11 and the second TVS transistor D12, and the instantaneous current generated by the electrostatic high-voltage pulse passes through the first TVS transistor D11 and/or The second TVS tube D12 is led to the ground, thereby realizing ESD protection for the back-end components; when the instantaneous high-voltage pulse ends, the first TVS tube D11 and the second TVS tube D12 automatically return to a high resistance state, The audio signal input/output of the audio circuit assembly 100 is not affected.

In one embodiment, the first TVS tube D11 and the second TVS tube D12 are preferably bidirectional TVS tubes.

In one embodiment, the electrostatic protection unit 40 may also have a circuit structure as shown in FIG. 4 . The electrostatic protection unit 40 includes a third resistor R3, a fourth resistor R4, a first voltage regulator D21 and a second voltage regulator D22. The negative electrode of the first voltage regulator tube D21 is electrically connected to the common terminal of the third capacitor C3 and the left channel pin LP1, and the positive electrode of the first voltage regulator tube D21 is electrically connected to the third resistor. One end of R3 and the other end of the third resistor R3 are grounded. The negative electrode of the second voltage regulator tube D22 is electrically connected to the common terminal of the fourth capacitor C4 and the right channel pin RP1, and the positive electrode of the second voltage regulator tube D22 is electrically connected to the fourth resistor. One end of R4 and the other end of the fourth resistor R4 are grounded. When an electrostatic high voltage pulse flows into the audio connector 10, an avalanche occurs in the first voltage regulator tube D21 and the second voltage regulator tube D22, and the instantaneous current generated by the electrostatic high voltage pulse can pass through the first voltage regulator tube D21, the third resistor R3 and/or the second voltage regulator D22 and the fourth resistor R4 are led to the ground, thereby realizing ESD protection for the back-end components; when the instantaneous high voltage pulse ends, the first voltage regulator The tube D21 and the second voltage regulator tube D22 automatically return to a high-impedance state, which does not affect the audio signal input/output of the audio circuit assembly 100 .

The above audio circuit components can effectively avoid noise interference and electrostatic damage, improve the sound quality and stability of audio products, and have low cost.

For those skilled in the art, other corresponding changes or adjustments can be made according to the inventive solution and inventive concept of the present invention combined with the actual needs of production, and these changes and adjustments should all belong to the scope disclosed by the present invention.

Claims (8)

1. an audio circuit assembly, comprising an audio connector, the audio connector is used for plugging with peripheral audio equipment, it is characterized in that, described audio circuit assembly also comprises: a signal processing unit, electrically connected to the audio connector, for outputting a first audio signal to the audio connector or receiving a second audio signal input by the audio connector; a first filtering unit, electrically connected between the signal processing unit and the audio connector, for filtering out the noise signal contained in the first audio signal or the second audio signal; and The electrostatic protection unit is electrically connected to the common end of the first filter unit and the audio connector, and is used for electrostatic protection of the signal processing unit and the first filter unit. 2. The audio circuit assembly according to claim 1, wherein the signal processing unit comprises an audio processing chip, and the audio processing chip comprises a left channel signal pin and a right channel signal pin, the The left channel signal pin and the right channel signal pin are respectively electrically connected to the first filtering unit. 3. The audio circuit assembly of claim 2, wherein the first filtering unit comprises: a first capacitor, one end of which is electrically connected to the left channel signal pin; a first resistor, one end is electrically connected to the other end of the first capacitor, and the other end is electrically connected to the left channel pin of the audio connector; a second capacitor, one end of which is electrically connected to the right channel signal pin; and One end of the second resistor is electrically connected to the other end of the second capacitor, and the other end is electrically connected to the right channel pin of the audio connector. 4. The audio circuit assembly of claim 3, wherein the first filter unit further comprises a first magnetic bead and a second magnetic bead, the first magnetic bead is electrically connected to the first resistor and the Between the left channel pins, the second magnetic beads are electrically connected between the second resistor and the right channel pins. 5. The audio circuit assembly of claim 3, wherein the electrostatic protection unit comprises: a first TVS tube, one end is electrically connected to the common end of the first resistor and the audio connector, and the other end is grounded; and One end of the second TVS tube is electrically connected to the common end of the second resistor and the audio connector, and the other end is grounded. 6. The audio circuit assembly of claim 5, further comprising a second filter unit, the second filter unit comprising a third capacitor and a fourth capacitor, and one end of the third capacitor is electrically connected to the The common terminal of the first TVS tube and the first resistor, the other end of the third capacitor is grounded, and one end of the fourth capacitor is electrically connected to the common terminal of the second TVS tube and the second resistor , and the other end of the fourth capacitor is grounded. 7 . The audio circuit assembly according to claim 6 , wherein the capacitance value of the third capacitor is much smaller than that of the first capacitor, and the capacitance value of the fourth capacitor is much smaller than that of the second capacitor 7 . Capacitance value of the capacitor. 8. The audio circuit assembly of claim 3, wherein the electrostatic protection unit comprises: a first voltage regulator, the negative electrode is electrically connected to the common terminal of the first resistor and the audio connector; a third resistor, one end of which is electrically connected to the positive electrode of the first voltage regulator tube, and the other end is grounded; a second voltage regulator, the negative electrode is electrically connected to the common terminal of the second resistor and the audio connector; and One end of the fourth resistor is electrically connected to the positive electrode of the second voltage regulator tube, and the other end is grounded.

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