WM8766

Preliminary Technical Data

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PTD Rev 2.3 February 2004

22

DMUTE [2:0]

DAC CHANNEL 1

DAC CHANNEL 2

DAC CHANNEL 3

000

Not MUTE

Not MUTE

Not MUTE

001

MUTE

Not MUTE

Not MUTE

010

Not MUTE

MUTE

Not MUTE

011

MUTE

MUTE

Not MUTE

100

Not MUTE

Not MUTE

MUTE

101

MUTE

Not MUTE

MUTE

110

Not MUTE

MUTE

MUTE

111

MUTE

MUTE

MUTE

Setting the MUTEALL register bit will apply a 'soft' mute to the input of all the DAC digital filters:

REGISTER ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

0000010

DAC Mute

0

MUTEALL

0

Soft Mute Select:

0 : Normal operation

1: Soft mute all channels

Refer to Figure 7 for the plot of application and release of soft mute.

Figure 17 Application and Release of Soft Mute

Figure 17 shows the application and release of MUTE whilst a full amplitude sinusoid is being played

at 48kHz sampling rate. When MUTE (lower trace) is asserted, the output (upper trace) begins to

with a time constant of approximately 64 input samples. If MUTE is applied to all channels for 1024

asserted, the output will restart immediately from the current input sample.

Note that all other means of muting the DAC channels: setting the PL[3:0] bits to 0, setting the

PDWN bit or setting attenuation to 0 will cause much more abrupt muting of the output.

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

0

0.001

0.002

0.003

0.004

0.005

0.006

Time(s)