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PCM1780, PCM1781, PCM1782

SLES132A – MARCH 2005 – REVISED APRIL 2005

B15

B14

B13

B12

B11

B10

B9

B8

B7

B6

B5

B4

B3

B2

B1

B0

REGISTER 20

0

IDX6

IDX5

IDX4

IDX3

IDX2

IDX1

IDX0

RSV

RSV

FLT

RSV

RSV

FMT2

FMT1

FMT0

NOTE: RSV indicates a reserved bit that should be set to 0.

FMT[2:0]: Audio Interface Data Format

Default value: 101

FMT[2:0]

Audio Data Format Selection

000

24-bit right-justified format, standard data

001

20-bit right-justified format, standard data

010

18-bit right-justified format, standard data

011

16-bit right-justified format, standard data

100

101

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

110

Reserved

111

Reserved

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

available format options.

FLT: Digital Filter Rolloff Control

Default value: 0

FLT = 0

Sharp rolloff (default)

FLT = 1

Slow rolloff

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

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

Performance Curves section of this data sheet

B15

B14

B13

B12

B11

B10

B9

B8

B7

B6

B5

B4

B3

B2

B1

B0

REGISTER 21

0

IDX6

IDX5

IDX4

IDX3

IDX2

IDX1

IDX0

RSV

RSV

RSV

RSV

RSV

RSV

RSV

DAMS

NOTE: RSV indicates a reserved bit that should be set to 0.

DAMS: Digital Attenuation Mode Select

Default value: 0

DAMS = 0

Fine step, 0.5 dB/step for 0 to –63 dB range (default)

DAMS = 1

Wide range, 1 dB/step for 0 to –100 dB range

The DAMS bit is used to select the digital attenuation mode.

23