PCM4104

SBAS291C − AUGUST 2003 − REVISED DECEMBER 2004

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Register 4: Attenuation Control Register – Channel 4

BIT 7 (MSB)

BIT 6

BIT 5

BIT 4

BIT 3

BIT 2

BIT 1

BIT 0 (LSB)

AT47

AT46

AT45

AT44

AT43

AT42

AT41

AT40

This register controls the digital output attenuation for Channel 4.

Default: AT4[7:0] = 255, or 0dB

Let N = AT4[7:0].

For N = 16 to 255, Attenuation (dB) = 0.5 x (255 – N)

For N = 0 to 15, Attenuation (dB) = Infinite (Muted)

Register 5: Function Control Register

BIT 7 (MSB)

BIT 6

BIT 5

BIT 4

BIT 3

BIT 2

BIT 1

BIT 0 (LSB)

MUT4

MUT3

MUT2

MUT1

ZDM

PHASE

DEM1

DEM0

This register controls various D/A converter functions, including de-emphasis filtering, output phase reversal, zero data

mute, and per-channel soft muting.

DEM[1:0]

Digital De-Emphasis

De-emphasis is available for Single Rate mode only.

De-emphasis is disabled for Dual and Quad Rate modes.

DEM1

DEM0

De-Emphasis Selection

0

0

De-emphasis disabled (default)

0

1

De-emphasis for fS = 48kHz

1

0

De-emphasis for fS = 44.1kHz

1

1

De-emphasis for fS = 32kHz

PHASE

Output Phase

PHASE

Output Phase

0

Noninverted (default)

1

Inverted

ZDM

Zero Data Mute

ZDM

Zero Mute

0

Disabled (default)

1

Enabled

MUT[4:1]

Soft Mute

MUTx

D/A Converter Output

0

On (default)

1

Muted

NOTE: x = channel number.