A circuit for sharing audio power amplifiers between analog and differential audio sources

Abstract

The invention discloses a circuit for achieving power amplification of shared audios of an analog audio source and a differential audio source. The circuit comprises a switching power supply input circuit, an analog audio source input circuit, a differential audio source input circuit, an audio source input selection circuit, an audio processing circuit, an audio power amplification circuit and a loudspeaker, wherein the audio processing circuit is used for filtering, amplification and impedance matching of two types of audio signals, analog / differential audio signals output by the audio source input selection circuit are processed and then are output to the audio power amplification circuit, the audio power amplification circuit amplifies the audio signals, and then the audio signals are broadcast by the loudspeaker. The circuit can be compatible with input of the analog audio signals and input of the differential audio signals, avoids mutual interference, can achieve independent output or mixed output of the two paths of audio signals, and is low in hardware cost, small in size and low in power consumption.

Description

technical field [0001] The invention relates to the technical field of audio power amplifier products, in particular to a circuit for realizing the shared audio power amplifier of analog and differential sound sources. Background technique [0002] With the rapid development of electronic technology, audio equipment has been closely related to everyone's daily life. For some sound source external devices, the sound system is to process and amplify the small audio signal transmitted from the signal source through the audio power amplifier, and then output it to the speaker, and the speaker vibrates to emit sound. However, the external device of the sound source is often not well compatible with the two types of analog and differential audio input signals. Due to the difference in the output impedance of the pre-circuit of the two types of sound sources and the different types of audio signals, the two types of audio signals cannot be directly connected in parallel. Otherwise...

AI Technical Summary

Problems solved by technology

However, the external device of the sound source is often not well compatible with the two types of analog and differential audio input signals. Due to the difference in the output impedance of the pre-circuit of the two types of sound sources and the different types of audio signals, the two types of audio signals cannot be directly connected in parallel. to the input end of the audio power amplifier circuit, otherwise the two types of audio signals will interfere with each other, which will directly affect the user experience or even fail to output normally. If two audio power amplifiers are used, the hardware cost, size and power consumption of the terminal equipment will be seriously increased.

[0003] For this reason, Chinese patent ZL200810007714.X discloses a multi-audio source shared audio power amplifier circuit and its control method, through an analog switch to switch the multi-tone source audio signal output by the multi-tone source output series resistance to the audio power amplifier input circuit, so as to achieve impedance matching And audio source channel selection, its disadvantage is that it cannot realize the amplification of two different audio source signals, it is not compatible with the input of two types of analog and differential audio signals, and one of the audio signals can only be selected through the analog switch to the audio power amplifier input circuit, Unable to mix and output two or more audio signals

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