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In this lesson, we talk about the working conditions of small audio

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A small audio is a main chip that drives the speakers

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Let's take a look at the frame diagram

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This audio amplifier is a small audio, it is to drive the speaker

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On the left are some chips that control it and give it working conditions

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For example, the power supply provides power to the audio power amplifier,

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and the CPU inputs the sound signal to the audio power amplifier through the I2S bus

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The working conditions of the audio power amplifier are power supply, reset, I2C control bus,

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transmission bus, interrupt signal, boost circuit, and its output circuit for amplified sound

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Its working conditions are similar to other chips

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There are generally two power supplies for audio chips

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This power supply is its boost circuit, which provides power to the small audio after the boost

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That is, the small audio chip itself has a boost circuit

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This is its power supply

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The main power supply of different mobile phones is different,

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but they all have 1.8 volt power supply

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The second working condition is the reset signal

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The reset signal is usually the CPU to reset the small audio

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We can know through the line that one end of this reset signal is connected to the CPU,

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and the other end is connected to the small audio

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The third is the control bus, which is the I2C bus

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The CPU controls when the small audio works and when it does not work through the I2C bus

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The fourth is the transmission bus of sound data

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The sound signal is transmitted through the I2S bus, MISO bus, or PDM bus

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The fifth working condition is the interrupt signal

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The interrupt signal is generally sent to the CPU by the small audio chip

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We can see through the connection method of the line that

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one end of this interrupt signal is connected to the small audio, and the other end is connected to the CPU

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We sum up, its working conditions are power supply, reset, control bus, sound transmission bus and interrupt signal

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Although the mobile phones are different, the position numbers of the chips of the mobile phones are different,

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and the models are different, but their working conditions are similar

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This is the working condition and circuit structure of small audio

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That's all for this lesson