The PD63310 is an LSI that features two channels each of on-chip 16-bit ADC and DAC circuits for mutual conversion between digital signals and audio signals (having a maximum signal bandwidth of 24 kHz). The analog signal input block enables mixed input of four different stereo signals and one monaural signal, and the volume of each signal can be controlled before mixing. The PD63310 also features two on-chip microphone amplifiers (mic amps) and gain is adjustable between 10 and 30 dB. The analog signal output block enables mixed output of analog signals output by the DAC and four different stereo analog signals, and the volume of each signal can be controlled before mixing. The digital audio signal I/O block supports a serial interface for audio applications (two's complement, MSB first). A 6-bit parallel port are used for the various volume settings, with volume settings selectable (in 1.5-dB steps) from 46.5 dB to 0 dB, as well as a mute setting.