AK4561 Datasheet, PDF (41/48 Pages) Asahi Kasei Microsystems – 16bit CODEC with built-in ALC and MIC/HP-Amp

ASAHI KASEI
AKM CONFIDENTIAL
[AK4561]
(1) Recovery waiting counter reset level (LMTH) or reference value of recovery operation (REF6-0)
Zero crossing detect
Gain Level (RATT)
Limiter detection level (LMTH)
(2) Zero crossing timeout (ZTM1-0) & Recovery waiting time (WTM1-0)
Figure 29. The continuous ALC Recovery Operation
(1). When the input signal exceeds the ALC recovery waiting counter reset level, the ALC recovery operation stops, the
ALC recovery operation is repeated when input signal level is below “LMTH” again. When the IPGA value by
repeating the ALC recovery operation reaches the reference level (REF6-0 bits), the ALC recovery operation stops.
(2). ZTM bit sets zero crossing timeout and WTM bit sets the ALC recovery operation period. When the ALC recovery
waiting time (WTM1-0 bits) is shorter than zero crossing timeout period of ZTM1-0 bit, the ALC recovery is operated
by the zero crossing timeout period of ZTM1-0 bit. Therefore, in this case the auto recovery operation period is not
constant.
Rev. 0.9
- 41 -
2000/09