ASAHI KASEI

[AK4342]

MS0506-E-02

2006/07

- 20 -

Digital Volume

The AK4342 includes channel independent digital output volumes (ATT) with 256 levels at linear step including MUTE.

These volumes are in front of the DAC and can attenuate the input data from 0dB to –48dB and mute. Changing levels are

executed via soft changes without any pop noise. The transition time of 1 level and all 256 levels is shown in Table 7.

At DATTC bit = “1”, ATTL7-0 bits control both Lch and Rch attenuation level, while register values of ATTL7-0 bits are

not written to ATTR7-0 bits. At DATTC bit = “0”, ATTL7-0 bits control Lch level and ATTR7-0 bits control Rch level.

ATTL7-0 bits

ATTR7-0 bits

ATT (dB)

FFH

Default

•

20 log

01H

00H

Mute

Table 6. Digital Volume Gain Table

Transition Time

STS1 bit

STS0 bit

Sampling Speed

1 Level

255 to 0

Half Speed Mode

1LRCK

255LRCK

Normal Speed Mode

2LRCK

510LRCK

0

0

Double Speed Mode

4LRCK

1020LRCK

Half Speed Mode

2LRCK

510LRCK

Normal Speed Mode

4LRCK

1020LRCK

Default

0

1

Double Speed Mode

8LRCK

2040LRCK

Half Speed Mode

4LRCK

1020LRCK

Normal Speed Mode

8LRCK

2040LRCK

1

0

Double Speed Mode

16LRCK

4080LRCK

Half Speed Mode

8LRCK

2040LRCK

Normal Speed Mode

16LRCK

4080LRCK

1

1

Double Speed Mode

32LRCK

8160LRCK

Table 7. Transition Time for Digital Volume