The analog inputs have PGA on the front end, allowing dynamic range optimization with a wide range of input sources. The microphone amplifiers have a programmable gain from -12dB to +35.25dB to handle both amplified microphones. In addition to a digital high pass filter to remove DC offset voltages, the ADC also features voice band digital filtering.  Voice-band data is accepted by the audio interface (I²S) .  The DAC converter path includes filtering and mixing, programmable-gain amplifiers (PGA) , and soft muting. The digital interfaces, 2-Wire or SPI, have independent supply voltage to allow integration into multiple supply systems. The NAU8812 operates at supply voltages from 2.5V to 3.6V, although the digital core can operate at voltage as low as 1.71V to save power.