PCM1730

SLES021 – NOVEMBER 2001

9

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audio data formats and timing

left-justified. The data formats are shown in Figure 4. Data formats are selected by using the FMT2 (pin 14),

FMT1 (pin 13) and FMT0 (pin 12) as shown in Table 2. All formats require binary 2’s complement, MSB-first

audio data. Figure 5 shows a detailed timing diagram for the serial audio interface.

Table 2. Audio Data Format Select

FMT2

(PIN 14)

FMT1

(PIN 13)

FMT0

(PIN 12)

FORMAT

Low

Low

Low

16-bit standard format, right-justified

Low

Low

High

20-bit standard format, right-justified

Low

High

Low

24-bit standard format, right-justified

Low

High

High

24-bit MSB-first, left-justified format

High

Low

Low

16-bit I2S format

High

Low

High

24-bit I2S format

High

High

Low

Reserved

High

High

High

Reserved

zero detect

When the PCM1730 detects that the audio input data in L-channel or R-channel is continuously zero for 1024

soft mute

The PCM1730 supports mute operation. When MUTE (pin 15) is set to HIGH, both analog outputs are turned

muting of DAC output.

de-emphasis

The PCM1730 supports de-emphasis filter performance for sampling frequency 32 kHz, 44.1 kHz, 48 kHz.

Sampling frequency is selectable by using DEMP1 (pin 11) DEMP0 (pin 10) as shown in Table 3.

Table 3. De-Emphasis Control

DEMP1 (PIN 11)

DEMP0(PIN 10)

DE-EMPHASIS FUNCTION

Low

Low

Disabled

Low

High

48 kHz

High

Low

44.1 kHz

High

High

32 kHz