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FMT[2:0] – Audio Interface Data Format

FLT – Digital Filter Rolloff Control

PCM1742

SBAS176A – DECEMBER 2000 – REVISED APRIL 2005

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B0

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0

IDX6

IDX5

IDX4

IDX3

IDX2

IDX1

IDX0

RSV

RSV

FLT

RSV

RSV

FMT2

FMT1

FMT0

Default value: 101

The FMT[2:0] bits are used to select the data format for the serial audio interface. The following table shows the

available format options.

FMT[2:0]

Audio Data Format Selection

000

24-bit standard format, right-justified data

001

20-bit standard format, right-justified data

010

18-bit standard format, right-justified data

011

16-bit standard format, right-justified data

100

I2S format, 16- to 24-bit

101

Left-justified format, 16- to 24-bit (default)

110

Reserved

111

Reserved

Default value: 0

FLT = 0

Sharp rolloff (default)

FLT = 1

Slow rolloff

The FLT bit allows the user to select the digital filter rolloff that is best suited to their application. Two filter rolloff

selections are available: sharp or slow. The filter responses for these selections are shown in the Typical

Performance Curves section of this data sheet.

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