Systems and methods for reducing artifacts and improving performance of a multi-path analog-to-digital converter

A processing system comprising:

• a plurality of processing paths including a first processing path and a second processing path, wherein:
• the first processing path comprises a first analog-to-digital converter, wherein the first processing path is configured to convert an analog signal into a first digital signal;
• and
• the second processing path comprises a second analog-to-digital converter, wherein the second processing path is configured to convert the analog signal into a second digital signal;
• and
• a controller configured to:
• select one of the first digital signal and the second digital signal as a digital output signal of the processing system based on a magnitude of the analog signal;
• when changing selection between the first digital signal and the second digital signal as the digital output signal, transition between the first digital signal and the second digital signal such that during the transition, the digital output signal is a weighted average of the first digital signal and the second digital signal wherein a weight of the first digital signal relative to a weight of the second digital signal increases or decreases during the transition;
• ensure an inaudible change in noise floor when transitioning between the first processing path and the second processing path by:
• detecting a condition for auditory masking of the change in the noise floor;
• and
• transitioning between the first processing path and the second processing path in response to detecting the condition.

A method of processing an audio signal in a multiple-path analog-to-digital converter system to achieve higher performance for a longer duration for certain frequencies of the audio signal when an error for certain frequencies is lesser than a corresponding error for other frequencies, comprising:

• providing a frequency-dependent threshold for switching between signal paths of the multiple-path analog-to-digital converter system;
• switching between signal paths of the multiple-path analog-to-digital converter system in response to the audio signal having a magnitude at a frequency of the audio signal increasing above the frequency-dependent threshold at the frequency;
• wherein the multiple-path analog-to-digital converter system comprises a first processing path for processing audio signals of lower magnitudes and a second processing path for processing audio signals of higher magnitudes;
• determining whether a magnitude of the audio signal exceeds a second threshold indicative of a likelihood of audio distortion due to signal clipping if the audio signal is processed by the first processing path;
• and
• selecting the second processing path if the audio signal exceeds the second threshold, regardless of whether or not the audio signal has a magnitude at any frequency of the audio signal increasing above the frequency-dependent threshold.

A processing system comprising:

• a plurality of processing paths including a first processing path and a second processing path, wherein:
• the first processing path comprises a first analog-to-digital converter, wherein the first processing path is configured to convert an analog signal into a first digital signal;
• the second processing path comprises a second analog-to-digital converter, wherein the second processing path is configured to convert the analog signal into a second digital signal;
• and
• wherein the first processing path is for processing audio signals of lower magnitudes and the second processing path is for processing audio signals of higher magnitudes;
• and
• a controller configured to:
• switch between the first digital signal and the second digital signal in response to the analog signal having a magnitude at a frequency of the analog signal increasing above a frequency-dependent threshold at the frequency;
• determine whether a magnitude of the analog signal exceeds a second threshold indicative of a likelihood of audio distortion due to signal clipping if the analog signal is processed by the first processing path;
• and
• select the second processing path if the analog signal exceeds the second threshold, regardless of whether or not the analog signal has a magnitude at any frequency of the analog signal increasing above the frequency-dependent threshold.

A processing system comprising:

• a plurality of processing paths including a first processing path for processing audio signals of lower magnitudes and a second processing path for processing audio signals of higher magnitudes, wherein:
• the first processing path comprises a first analog-to-digital converter, wherein the first processing path is configured to convert an analog signal into a first digital signal;
• and
• the second processing path comprises a second analog-to-digital converter, wherein the second processing path is configured to convert the analog signal into a second digital signal;
• and
• a controller configured to:
• generate an adjustable fading coefficient defining the relative levels by which the respective outputs of the first processing path and the second processing path contribute to an overall digital output signal generated by a multiple-path analog-to-digital converter system during a transition between selection of the first processing path and the second processing path;
• and
• set a minimum fading level of the fading coefficient to an intermediate fading level between that at which the first processing path contributes entirely to the overall digital output signal and that at which the second processing path contributes entirely to the overall digital output signal.