Audio interface circuit and its control method, audio equipment

Abstract

The present invention provides an audio interface circuit, its control method, and audio equipment. The method includes: an arbitration logic circuit measures the clock frequency offset between the second audio interface and the first audio interface; the arbitration logic circuit obtains the clock according to the clock frequency offset. Adjust the first current value of the parameter; the arbitration logic circuit detects the buffer status of the first audio interface, if the first buffer flag event is detected, the arbitration logic circuit increases the adjustment amount in the first current value and increases the first current value If the second cache flag event is detected, the arbitration logic circuit reduces the adjustment amount in the first current value and increases the number of clocks in the first current value. The invention can effectively relieve the audio noise problem caused by the clock deviation between a master-mode audio interface and a slave-mode audio interface, and is simpler and more efficient than the prior art.

Description

technical field [0001] The invention relates to the field of audio technology, in particular to an audio interface circuit, a control method thereof, and an audio device. Background technique [0002] When audio data is transmitted between different audio devices (such as sound cards, mobile phones, computers, speakers, etc.), since the clock sources of different devices are different, overflow or underflow will inevitably occur during the process of receiving and sending data. And because audio is continuous data, when overflow or underflow occurs, frame loss is likely to occur, resulting in audio noise. For example, for two different audio devices, although theoretically both are 12M crystal oscillators, and the I2S frequency is 48KHz, the clock sources of the two audio devices are relatively independent. Due to the natural deviation of the clock (generally not greater than ±100PPM), the two audio The clock deviation between devices will cause the problem of data transmis...

AI Technical Summary

Problems solved by technology

[0002] When audio data is transmitted between different audio devices (such as sound cards, mobile phones, computers, speakers, etc.), since the clock sources of different devices are different, overflow or underflow will inevitably occur during the process of receiving and sending data. And because audio is continuous data, when overflow or underflow occurs, frame loss is likely to occur, resulting in audio noise

For example, for two different audio devices, although theoretically both are 12M crystal oscillators, and the I2S frequency is 48KHz, the clock sources of the two audio devices are relatively independent. Due to the natural deviation of the clock (generally not greater than ±100PPM), the two audio The clock deviation between devices will cause the problem of data transmission out of synchronization, and the data will inevitably overflow or underflow during the process of receiving and sending, which will easily lead to sound loss or distortion.

[0003] In order to solve the above problems, most of the existing technologies achieve the purpose of synchronization by recovering the clock, such as using phase-locked loop synchronization or gaderner algorithm synchronization, but these methods are relatively complicated to implement

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