CN221509786U - 2.1 Sound channel power amplifier system - Google Patents

Abstract

The utility model application provides a 2.1-channel power amplifier system, comprising: a first power amplifier unit, a second power amplifier unit, a first speaker unit, a second speaker unit and a third speaker unit, wherein the first power amplifier unit is used for in-phase amplification, the second power amplifier unit is used for inverting amplification, the first speaker unit and the third speaker unit are used for outputting stereo of left and right channels, the second speaker unit is used for outputting bass audio, the first speaker unit is connected to the first power amplifier unit in positive phase, the third speaker unit is connected to the second power amplifier unit in reverse phase, and the second speaker unit is connected to the output ends of the first power amplifier unit and the second power amplifier unit. This design cleverly utilizes the basically identical characteristics of the bass frequency bands of stereo audio signals, and realizes power amplification of the 2.1-channel system with only two power amplifiers, thereby saving one subwoofer power amplifier and reducing costs. It is particularly suitable for 2.1-channel speakers with an integrated design that require low cost.

Description

A 2.1-channel power amplifier system

Technical Field

The utility model relates to the technical field of audio equipment, in particular to a 2.1-channel power amplifier system.

Background Art

2.1-channel audio is a common audio system consisting of two stereo speakers and a subwoofer. Among them, "2" represents two stereo speakers, which are used to output audio signals for the left and right channels respectively; ".1" represents the subwoofer, which is used to output bass frequency sounds. This configuration can provide a richer music experience and more realistic sound effects. The 2.1-channel power amplifier system is mainly responsible for providing sufficient power to drive two stereo speakers and a subwoofer. In a 2.1-channel system, the function of the power amplifier is to amplify the audio signals from the front devices (such as audio sources, preamplifiers, etc.) and distribute them to the speakers and subwoofers of the left and right channels.

In the related art, a traditional 2.1-channel power amplifier system is generally designed with a 3-channel power amplifier, which is respectively connected to two stereo speakers and a subwoofer. The 3-channel power amplifier is used to drive each audio channel (left channel, right channel and subwoofer). However, in some occasions where sufficiently low cost is required, such a design architecture may not meet the cost requirements.

Utility Model Content

In view of the above problems, an embodiment of the utility model provides a 2.1-channel power amplifier system, which includes: a first power amplifier unit, a second power amplifier unit, a first speaker unit, a second speaker unit and a third speaker unit, wherein the first power amplifier unit is used for in-phase amplification, the second power amplifier unit is used for inverting amplification, the first speaker unit and the third speaker unit are used to output stereo of left and right channels, the second speaker unit is used to output bass audio, the first speaker unit is connected to the first power amplifier unit in positive phase, the third speaker unit is connected to the second power amplifier unit in reverse phase, and the second speaker unit is connected to the output ends of the first power amplifier unit and the second power amplifier unit.

In some possible implementations, the first power amplifier unit and the second power amplifier unit are the same type of single-ended output power amplifier units.

In some possible implementations, the first power amplifier unit includes an audio power amplifier chip U1, the second power amplifier unit includes an audio power amplifier chip U2, the first speaker unit includes a speaker LS1, the second speaker unit includes a speaker LS2, and the third speaker unit includes a speaker LS3, wherein the positive pole of the speaker LS1 and the positive pole of the speaker LS2 are connected to the output end of the audio power amplifier chip U1, and the negative pole of the speaker LS2 and the negative pole of the speaker LS3 are connected to the output end of the audio power amplifier chip U2.

In some possible implementations, the cathode of the speaker LS1 and the anode of the speaker LS3 are both grounded.

In some possible implementations, the models of the audio power amplifier chip U1 and the audio power amplifier chip U2 are TDA2030A.

In some possible implementations, a capacitor C13 is connected between the positive electrode of the speaker LS1 and the output end of the audio power amplifier chip U1.

In some possible implementations, an inductor L1 is connected between the positive electrode of the speaker LS2 and the output end of the audio power amplifier chip U1.

In some possible implementations, a capacitor C14 is connected between the cathode of the speaker LS3 and the output end of the audio power amplifier chip U2.

The 2.1-channel power amplifier system provided by the embodiment of the utility model includes a first power amplifier unit, a second power amplifier unit, a first speaker unit, a second speaker unit and a third speaker unit, wherein the first power amplifier unit is used for in-phase amplification, the second power amplifier unit is used for inverting amplification, the first speaker unit and the third speaker unit are used for outputting stereo of left and right channels, in order to make the first speaker unit and the third speaker unit finally obtain the same phase, the first speaker unit is connected to the first power amplifier unit in positive phase, and the third speaker unit is connected to the second power amplifier unit in reverse phase. Under this circuit structure, by connecting the second speaker unit for outputting bass audio to the output ends of the first power amplifier unit and the second power amplifier unit, under the condition that the speaker impedances are the same, the second speaker unit can obtain a signal output amplitude of 2 times, and obtain a power output of 4 times that of the first speaker unit and the third speaker unit. This design cleverly utilizes the characteristics that the bass bands of stereo audio signals are basically the same, and only two power amplifiers are used to realize the power amplification of the 2.1-channel system, thereby saving one subwoofer power amplifier and reducing the cost, and is particularly suitable for 2.1-channel speakers with an integrated design and requiring low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a block diagram of a module of an embodiment of the present utility model;

FIG2 is a schematic diagram of the circuit principle of an embodiment of the utility model;

Explanation of reference numerals: 100, first power amplifier unit; 200, second power amplifier unit; 300, first speaker unit; 400, second speaker unit; 500, third speaker unit.

DETAILED DESCRIPTION

The overall idea of the technical solution provided by the utility model is as follows:

Please refer to FIG1 , a 2.1-channel power amplifier system includes:

A first power amplifier unit 100, a second power amplifier unit 200, a first speaker unit 300, a second speaker unit 400 and a third speaker unit 500, wherein the first power amplifier unit 100 is used for in-phase amplification, the second power amplifier unit 200 is used for inverting amplification, the first speaker unit 300 and the third speaker unit 500 are used to output left and right channel stereo, the second speaker unit 400 is used to output bass audio, the first speaker unit 300 is connected to the first power amplifier unit 100 in positive phase, the third speaker unit 500 is connected to the second power amplifier unit 200 in reverse phase, and the second speaker unit 400 is connected to the output ends of the first power amplifier unit 100 and the second power amplifier unit 200.

The first power amplifier unit 100 is used for in-phase amplification, the second power amplifier unit 200 is used for inverting amplification, the first speaker unit 300 and the third speaker unit 500 are used for outputting left and right channel stereo. In order to make the first speaker unit 300 and the third speaker unit 500 finally obtain the same phase, the first speaker unit 300 is connected to the first power amplifier unit 100 in positive phase, and the third speaker unit 500 is connected to the second power amplifier unit 200 in reverse phase. In this circuit structure, by connecting the second speaker unit 400 for outputting bass audio to the At the output end of the first power amplifier unit 100 and the second power amplifier unit 200, when the speaker impedance is the same, the second speaker unit 400 can obtain a signal output amplitude that is twice as high, and can obtain a power output that is four times that of the first speaker unit 300 and the third speaker unit 500. This design cleverly utilizes the basically identical low-frequency band characteristics of stereo audio signals, and uses only two power amplifiers to achieve power amplification of a 2.1-channel system, thereby saving one subwoofer amplifier and reducing costs. This design is particularly suitable for 2.1-channel speakers with an integrated design that require low cost.

The more specific principles are as follows:

Vo_L (output of the first power amplifier unit 100) = A*Vi_L (A is gain, Vi_L is the input signal amplitude of the first speaker unit 300)

Vo_R (output of the second power amplifier unit 200) = -A*Vi_R (A is gain, Vi_R is the input signal amplitude of the third speaker unit 500)

Due to the characteristics of stereo audio signals, in most cases, the subwoofer signals of the left and right channels are the same, that is:

Vi_SW＝Vi_L_SW＝Vi_R_SW (SW is a signal in the ultra-low frequency band)

Therefore, the signal amplitude obtained on the second speaker unit 400 (reproducing SW band sound) is:

Vo_SW=Vo_L-Vo_R=A*Vi_L_SW-(-A*Vi_R_SW)=2*A*Vi_SW

The power obtained on the second speaker unit 400 is (RL is the speaker impedance):

Po_SW＝(2A*Vi@SW)2/RL＝4*(Vi@SW/RL)

Therefore, it is concluded that, when the speaker impedance is the same, the second speaker unit 400, i.e. the subwoofer, can obtain a signal output amplitude that is twice that of the first speaker unit 300 and the third speaker unit 500, i.e. the power output of the left and right channel speakers. If the system needs to adjust the output power of the bass, it only needs to adjust the impedance design of the second speaker unit 400.

It can be understood that the signal provided to the second speaker unit 400 in this design is full-band. Therefore, there are two ways to filter out the mid- and high-frequency signals of the second speaker unit 400: one is to design a passive filtering network in the circuit of the second speaker unit 400 to filter out the mid- and high-frequency sounds. The passive filtering network is usually composed of components such as resistors, capacitors, and inductors, and can filter signals in a specific frequency range through appropriate values and connections; the second is to use a second speaker unit 400 whose physical frequency response basically has no mid- and high-frequency sounds. The frequency response characteristics of the speaker are determined by the physical parameters during its design and manufacturing process. Therefore, you can choose a second speaker unit 400 with a low-frequency response characteristic that suits your needs, so that it has the ability to filter out mid- and high-frequency signals in design. This method does not require additional filtering circuits.

In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment 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.

Furthermore, the first power amplifier unit 100 and the second power amplifier unit 200 are the same type of single-ended output power amplifier units.

Further, please refer to Figure 2, the first power amplifier unit 100 includes an audio power amplifier chip U1, the second power amplifier unit 200 includes an audio power amplifier chip U2, the first speaker unit 300 includes a speaker LS1, the second speaker unit 400 includes a speaker LS2, and the third speaker unit 500 includes a speaker LS3, wherein the positive pole of the speaker LS1 and the positive pole of the speaker LS2 are connected to the output end of the audio power amplifier chip U1, and the negative pole of the speaker LS2 and the negative pole of the speaker LS3 are connected to the output end of the audio power amplifier chip U2.

Furthermore, in this circuit design, the audio power amplifier chip U1 and the audio power amplifier chip U2 are power amplifiers with opposite output signal phases. They receive signals from an audio input source. The input signal is divided into two paths and enters the input ends of the audio power amplifier chip U1 and the audio power amplifier chip U2 respectively. Through the phase inversion and amplification of the audio power amplifier chip U1 and the audio power amplifier chip U2, the output signals of the audio power amplifier chip U1 and the audio power amplifier chip U2 can drive the speakers LS1, LS2 and LS3. Specifically, when the voltage at one output end of the audio power amplifier chip U1 and the audio power amplifier chip U2 rises, the voltage at the other output end drops, thereby generating a differential output. In this way, the output capabilities of the audio power amplifier chip U1 and the audio power amplifier chip U2 can be utilized, and higher peak power can be provided by balancing the differential output to drive the speakers LS1, LS2 and LS3.

Furthermore, the cathode of the speaker LS1 and the anode of the speaker LS3 are both grounded.

Furthermore, the models of the audio power amplifier chip U1 and the audio power amplifier chip U2 are TDA2030A.

Furthermore, a capacitor C13 is connected between the positive electrode of the speaker LS1 and the output end of the audio power amplifier chip U1. The capacitor C13 is connected between the positive electrode of the speaker LS1 and the output end of the audio power amplifier chip U1, and can block direct current and pass alternating current to avoid interference from direct current signals and ensure smooth transmission of audio signals.

Furthermore, an inductor L1 is connected between the positive electrode of the speaker LS2 and the output end of the audio power amplifier chip U1, and the inductor L1 plays a role in filtering and blocking high-frequency interference to ensure the quality and stability of the audio signal.

Furthermore, a capacitor C14 is connected between the negative electrode of the speaker LS3 and the output end of the audio power amplifier chip U2, and the function of the capacitor C14 is similar to that of the capacitor C13.

Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if these modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (8)

1. A 2.1 channel power amplifier system comprising: the audio amplifier comprises a first power amplifier unit, a second power amplifier unit, a first sound box unit, a second sound box unit and a third sound box unit, wherein the first power amplifier unit is used for in-phase amplification, the second power amplifier unit is used for reverse phase amplification, the first sound box unit and the third sound box unit are used for outputting stereo sound of left and right channels, the second sound box unit is used for outputting bass audio, the first sound box unit is connected with the first power amplifier unit in a normal phase, the third sound box unit is connected with the second power amplifier unit in a reverse phase, and the second sound box unit is connected with the output ends of the first power amplifier unit and the second power amplifier unit.

2. The 2.1 channel power amplification system of claim 1, wherein the first power amplification unit and the second power amplification unit are single-ended output power amplification units of the same type.

3. The 2.1 channel power amplification system of claim 1, wherein the first power amplification unit comprises an audio power amplification chip U1, the second power amplification unit comprises an audio power amplification chip U2, the first sound box unit comprises a speaker LS1, the second sound box unit comprises a speaker LS2, the third sound box unit comprises a speaker LS3, wherein an anode of the speaker LS1 and an anode of the speaker LS2 are connected with an output end of the audio power amplification chip U1, and a cathode of the speaker LS2 and an anode of the speaker LS3 are connected with an output end of the audio power amplification chip U2.

4. A 2.1 channel power amplification system as claimed in claim 3, characterized in that the negative pole of the loudspeaker LS1 and the positive pole of the loudspeaker LS3 are both connected to ground.

5. A 2.1 channel power amplification system as claimed in claim 3, wherein the audio power amplification chip U1 and the audio power amplification chip U2 are of the type TDA2030A.

6. A 2.1-channel power amplification system as claimed in claim 3, wherein a capacitor C13 is connected between the positive electrode of the speaker LS1 and the output end of the audio power amplification chip U1.

7. A 2.1-channel power amplification system as claimed in claim 3, wherein an inductance L1 is connected between the positive electrode of the speaker LS2 and the output end of the audio power amplification chip U1.

8. A 2.1-channel power amplification system as claimed in claim 3, wherein a capacitor C14 is connected between the negative electrode of the speaker LS3 and the output end of the audio power amplification chip U2.