Production Data

WM8766

w

PD Rev 4.1 July 2005

29

DAC DIGITAL VOLUME CONTROL

The DAC volume may also be adjusted in the digital domain using independent digital attenuation

control registers

REGISTER

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

7:0

LDA1[7:0]

11111111

(0dB)

Digital Attenuation data for Left channel DACL1 in 0.5dB steps. See

Table 16

0000000

Digital

Attenuation

DACL1

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store LDA1 in intermediate latch (no change to output)

1: Store LDA1 and update attenuation on all channels

7:0

RDA1[6:0]

11111111

(0dB)

Digital Attenuation data for Right channel DACR1 in 0.5dB steps.

See Table 16.

0000001

Digital

Attenuation

DACR1

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store RDA1 in intermediate latch (no change to output)

1: Store RDA1 and update attenuation on all channels.

7:0

LDA2[7:0]

11111111

(0dB)

Digital Attenuation data for Left channel DACL2 in 0.5dB steps. See

Table 16

0000100

Digital

Attenuation

DACL2

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store LDA2 in intermediate latch (no change to output)

1: Store LDA2 and update attenuation on all channels.

7:0

RDA2[7:0]

11111111

(0dB)

Digital Attenuation data for Right channel DACR2 in 0.5dB steps.

See Table 16

0000101

Digital

Attenuation

DACR2

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store RDA2 in intermediate latch (no change to output)

1: Store RDA2 and update attenuation on all channels.

7:0

LDA3[7:0]

11111111

(0dB)

Digital Attenuation data for Left channel DACL3 in 0.5dB steps. See

Table 16

0000110

Digital

Attenuation

DACL3

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store LDA3 in intermediate latch (no change to output)

1: Store LDA3 and update attenuation on all channels.

7:0

RDA3[7:0]

11111111

(0dB)

Digital Attenuation data for Right channel DACR3 in 0.5dB steps.

See Table 16

0000111

Digital

Attenuation

DACR3

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store RDA3 in intermediate latch (no change to output)

1: Store RDA3 and update attenuation on all channels.

7:0

MASTDA

[7:0]

11111111

(0dB)

Digital Attenuation data for all DAC channels in 0.5dB steps. See

Table 16

0001000

Master

Digital

Attenuation

(all channels)

8

UPDATE

Not latched

Controls simultaneous update of all Attenuation Latches

0: Store gain in intermediate latch (no change to output)

1: Store gain and update attenuation on all channels.

Note:

When MCLK is removed, digital volume settings are re-set to default (0dB). When MCLK is re-applied, the user

must write the desired volume level to the volume control registers.

L/RDAX[7:0]

ATTENUATION LEVEL

00(hex)

-

∞ dB (mute)

01(hex)

-127dB

:

:

:

:

:

:

FE(hex)

-0.5dB

FF(hex)

0dB

Table 16 Digital Volume Control Attenuation Levels