Two-way feedback single-power supply audio power amplifier

Abstract

The present invention discloses an audio power amplifier with two-way feedback and single power supply, which not only reduces the inhibition of low-frequency signals by the audio power amplifier, but also reduces the value of blocking DC coupling capacitance. In the technical proposal, the audio power amplifier comprises an audio amplification module, a first feedback path and a second feedback path. The audio amplification module comprises a first input end which is used for receiving input audio signals, a second input end which is used for receiving syntype reference voltage, a third input end which is used for receiving supply voltage, and an output end which is used for providing output audio signals; the first feedback path is connected between the output end of the audio amplification module and the inverted input end, and comprises a first resistance; the second feedback path is connected between the output end of the audio amplification module and the inverted input end, and comprises a second resistance, a capacitance and a third resistance which is used for regulating the gain of audio amplification. The audio power amplifier can be used in the field of audio power amplifier.

Description

technical field [0001] The invention relates to the field of microelectronics, in particular to audio amplifiers in mobile terminal equipment (such as mobile phones, etc.). Background technique [0002] figure 1 shows how a conventional single-supply audio power amplifier inverts and amplifies an input signal to drive a speaker load, see figure 1 . The audio amplifier module 101 is connected to the power supply VCC. The audio power amplifier module 101 includes an inverting input terminal for receiving an input signal Vin provided by a previous stage, a non-inverting input terminal for receiving a common-mode reference voltage Vcm, and an output terminal for outputting a signal Vx. After the audio power amplifier module 101 amplifies or attenuates the input signal Vin through the input resistor R1 and the feedback resistor R2, the output signal Vx obtained is loaded on the speaker RL through the DC blocking coupling capacitor Cout, that is, the connection point Vy. [00...

AI Technical Summary

Problems solved by technology

For a portable device like a mobile phone, a large capacitor means a large size, which will force the phone to increase in size to meet this demand. In addition, the large capacitor itself is more expensive

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