Overview
AK 4591 is a set of input selectors that selects 2 from 9 stereo inputs and distributes them to 2 built-in 24 bit ADC inputs.
These are CODECs of ADC4ch and DAC6ch. Since it is possible to select 2 types from 9 types of music sources, Suitable for rear seat entertainment applications in

FEATURE
Input selector
    -Select 2 arbitrary lines from 2 differential inputs + 7 single-ended inputs
ADC: 4 channels (2 stereo ADC lines)
    -24-bit 64 x Over-sampling delta sigma
    -DR, S / N: 97dBA (Fs: 48kHz when using differential input)
    -S / (N + D): 92 dB (Fs: when using 48 kHz differential input)
    -Supports sampling from 8kHz to 96kHz
    -Built-in HPF (High Pass Filter) for DC offset cancellation
DAC: 6 channels (3 stereo DACs)
    -24-bit 128 x Over-sampling advanced multi-bit
    -DR: 107dBA (6ch) (Fs: 48kHz)
    -S / N: 108dBA (6ch) (Fs: 48kHz)
    -S / (N + D): 90 dB (6 ch) (Fs: 48 kHz)
    -Supports sampling from 8kHz to 96kHz
Digital interface
    -Audio interface Serial data input 8ch
    -Audio interface serial data output 4ch
    -Microcomputer interface 1 input / output
Other
    -Power supply voltage: + 3.3V ± 0.3V
    -Operating temperature range: -40 ° C to 85 ° C
    -Package: 64pin LQFP (0.5mm pitch)