A 130dB PSRR, 108dB DR and 95dB SNDR, ground-referenced audio decoder with PSRR-enhanced load-adaptive Class-G 16Ohm headphone amplifiers

A Class-G headphone amplifier for Hi-Fi audio playback with high immunity to supply disturbance and Class-G switching noise is presented that achieves 130dB PSRR at 217Hz and higher than 100dB PSRR up to 20kHz. In addition, a Class-G amplifier with load-adaptive voltage supply rails selection and Class-G switching scheme improves the power efficiency for different impedances. Realized in 0.18μm CMOS, the decoder and amplifier together achieve 108dB DR and 95dB SNDR with a 16D headphone load.