Patent ID: 9559648
Date: 2017-01-31
CPC Classifications: H03F

Claim:
1. A method of audio signal processing, comprising: a first single ended (SE) closed loop channel receiving a first audio input signal (first input signal) at an inverting or non-inverting input of a first amplifier, said first amplifier configured as an integrating amplifier that is coupled in sequence to a first comparator, a first pulse width modulation (PWM) logic and pulse inject block, gate driver block, and output stage, wherein a first signal output of said first output stage is fed back to said inverting input of said first amplifier, and a second SE closed loop channel receiving a second audio input signal (second input signal) with a polarity reversed relative to said first input signal at an inverting or non-inverting input of at least a second amplifier, said second amplifier configured as an integrating amplifier that is coupled in sequence with a second comparator, a second PWM logic and pulse inject block, gate driver block, and output stage, wherein a second signal output of said second output stage is fed back to said inverting input of said second amplifier; during said audio signal processing dynamically changing a common-mode (CM) reference voltage level applied to a first current source which is coupled to pull current from said inverting or non-inverting input of said first amplifier and a second current source which is coupled to pull current from said inverting or non-inverting input of said second amplifier including: