Circuit eliminating shutdown POP sound of audio power amplifier

Abstract

The invention discloses a circuit eliminating a shutdown POP sound of an audio power amplifier. The circuit comprises a first triode, a second triode, a first resistor, a second resistor, a third resistor and a fourth resistor, the base of the first triode is connected with a power supply through the first resistor, the base of the first triode is connected with the ground through the second resistor, the collector of the first triode is connected with the power supply of an audio system through the third resistor, and the emitter of the first triode is connected with the ground. The base of the second triode is connected with the collector of the first triode and the connecting end of the third resistor, the collector of the second triode is connected with the power supply through the fourth resistor, the emitter of the second triode is connected with the ground, and the collector of the second triode and the connecting end of the fourth resistor are connected with a pair of ends of the audio power amplifier of the audio system respectively. The circuit has the advantage of being capable of eliminating the shutdown POP sound of the audio power amplifier when the audio system is in a power failure.

Description

technical field [0001] The invention relates to a circuit for eliminating the POP sound of an audio power amplifier shutting down in the field of integrated circuits. Background technique [0002] POP (popping) sound refers to the popping sound produced by the audio device on the earphone or speaker due to the transient impact of various operations at the moment of power-on, power-off and power-on stability, which will be produced by the human ear in the audio range A "puff" noise. This is what users don't want to hear, and system design engineers always try to avoid it. Usually this kind of transient impact is a very narrow sharp pulse. After the Fourier analysis is unfolded, the spectral components are very rich, and the energy distribution in the frequency domain is relatively average. Our purpose is to reduce its harmonic components in the range of 20Hz to 20kHz. For most human ears, if the peak-to-peak voltage of the signal is less than 10mV, it is inaudible. [0003...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a circuit for eliminating the POP sound when the audio power amplifier is turned off, which can solve the problem that the traditional audio system cannot eliminate the POP sound when the audio power amplifier is turned off

Images