Patent ID: 7339425

Claim:
An amplifier comprising: first and second comparators for respectively comparing a pair of differential signals with a half-swing modulation signal to generate first and second pulse-width-modulation (PWM) control signals, wherein said half-swing modulation signal has a voltage swing between a common mode voltage (V cm ) of said pair of differential signals and a preset voltage smaller than a voltage swing of said differential signals; an output switch comprising a pair of inputs coupled to receive said first and second PWM control signals to provide a ternary encoded output signal in response to said first and second PWM control signals; and means for providing said half-swing modulation signal, whereby generating said PWM control signals with said half-swing modulation signal enables said output switch to provide said ternary encoded output signal without intermediate ternary encoding of said PWM control signals interposed between said comparators and said output switch.