Audio artifact reduction in universal audio jack (UAJ) interface circuits
AssigneeCirrus Logic, Inc.
InventorsGaofeng Fan, Qi Cai, John B. Bowlerwell, Richard Turkson, Anindya Bhattacharya, Bhoodev Kumar
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AssigneeCirrus Logic, Inc.
InventorsGaofeng Fan, Qi Cai, John B. Bowlerwell, Richard Turkson, Anindya Bhattacharya, Bhoodev Kumar
Estimating the term…
Circuit techniques reduce or prevent audible artifacts in a Universal Audio Jack (UAJ) interface circuit, improving handling of mis-configuration/mis-attachment of devices. The interface includes at least one terminal for accepting an audio input signal or providing an audio line output signal coupled to an input or output of a first audio circuit. The first audio circuit operates from a low voltage domain and receives the audio input signal or provides the audio line output signal. A second circuit operates from a higher voltage domain and a switching circuit couples the at least one terminal to the second circuit. The output is slew-rate controlled to control a transition time of the output, so that audible artifacts in the audio input signal or the audio line output signal that could be generated by the switching circuit connecting the second circuit to the at least one terminal are avoided.
An audio interface circuit, comprising:
A method of preventing generation of audible artifacts by an audio interface circuit, comprising:
The method of 11, further comprising selecting a function of the at least one terminal between at least one of an audio line input or audio output function for providing an audio line output signal or accepting an audio input signal, and between a microphone bias output function, wherein the first audio circuit is an audio input or line output circuit coupled to the at least one terminal for receiving the audio input signal or supplying the audio line output audio signal, wherein the second circuit is a microphone bias driver having an output that provides the microphone bias output level coupled to the at least one terminal.
Dependencies are inferred from the claim text.