BPZ

Fade-In Start

DOUT

(Contents)

Fade-In Complete

Fade-Out Start

Fade-Out Complete

48/f

in or 48/fS

48/f

in or 48/fS

LRCK

Right-Channel

Left-Channel

BCK

DOUT

MSB

LSB

MSB

LSB

24-Bit, MSB-First, I S

2

Format 0: FMT = LOW

22 23 24

3

2

1

22 23 24

3

2

1

24-Bit, MSB-First, Left-Justified

BCK

LRCK

Right-Channel

Left-Channel

DOUT

1

22 23 24

3

2

1

MSB

LSB

MSB

LSB

22 23 24

3

2

1

Format 1: FMT = HIGH

PCM1808

www.ti.com

SLES177B – APRIL 2006 – REVISED AUGUST 2015

Figure 24. Audio Data Format (LRCK and BCK Work as Inputs in Slave Mode

and as Outputs in Master Mode)

7.3.5.3 Interface Timing

Figure 4 and Figure 5 illustrate the interface timing in slave mode and master mode, respectively.

7.4 Device Functional Modes

7.4.1 Fade-In and Fade-Out Functions

The PCM1808 device has fade-in and fade-out functions on DOUT (pin 9) to avoid pop noise, and the functions

come into operation in some cases as described in several following sections. Performance of the level changes

from 0 dB to mute or mute to 0 dB employs calculated pseudo S-shaped characteristics with zero-cross

detection. Because of the zero-cross detection, the time needed for the fade-in and fade-out depends on the

analog input frequency (fin). It takes 48 / fin to complete the processing. If there is no zero-cross during 8192 / fS,

a forced DOUT fade-in or fade-out occurs during 48 / fS (TIME OUT). Figure 25 illustrates the fade-in and fade-

out operation processing.

Figure 25. Fade-In and Fade-Out Operations

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