Datasheet

[AK4646]

MS0557-E-06 2011/06

- 41 -

The Volume at the ALC Operation

The current volume value at the ALC operation is reflected by VOL7-0 bits. It is enable to check the current volume value

with reading the register value of VOL7-0 bits.

VOL7-0bits GAIN(0dB)

F1H +36.0

F0H +35.625

EFH +35.25

: :

C5H +19.5

: :

92H +0.375

91H 0.0

90H -0.375

: :

2H -53.625

1H -54.0

0H MUTE

Table 31. Value of VOL7-0 bits

Example of ALC Operation

Table 32 and Table 33 show the examples of the ALC setting for recording and playback path.

fs=8kHz fs=44.1kHz

Data Operation Data Operation

LMTH1-0 Limiter detection Level 01

−4.1dBFS

ZELMN Limiter zero crossing detection 0 Enable 0 Enable

ZTM1-0 Zero crossing timeout period 01 32ms 11 23.2ms

WTM2-0

Recovery waiting period

*WTM2-0 bits should be the same data

as ZTM1-0 bits

001 32ms 100 46.4ms

IREF7-0 Maximum gain at recovery operation E1H +30dB E1H +30dB

IVL7-0,

IVR7-0

Gain of IVOL E1H +30dB E1H +30dB

LMAT1-0 Limiter ATT step 00 1 step 00 1 step

LFST Fast Limiter Operation 1 ON 1 ON

RGAIN1-0 Recovery GAIN step 00 1 step 00 1 step

RFST1-0 Fast Recovery Speed 00 4 times 00 4 times

ALC1 ALC enable 1 Enable 1 Enable

Table 32. Example of the ALC setting (Recording)