AK4561 Datasheet, PDF (42/48 Pages) Asahi Kasei Microsystems – 16bit CODEC with built-in ALC and MIC/HP-Amp

ASAHI KASEI
AKM CONFIDENTIAL
[AK4561]
3. Attention of IPGA writing operation
During the ALC operation, internal control register indicates the different value to the current IPGA value. And if the
writing value before and after the ALC operation is same, the IPGA value is not updated.
If the IPGA is the same value before and after the ALC operation, it needs to write the dummy command during the ALC
operation.
In Figure 30, the last IPGA value is reflected by doing the following sequence.
WR(IPGA=60H) → WR(ALC= “1”) → WR(ALC= “0”) → WR(IPGA=60H)
Internal State
Manual Mode
Control Register
Internal IPGA Value
60H
ALC operation
60H
60H --> 40H
Manual Mode
40H
(1)
(2) (3)
Figure 30. IPGA value during ALC operation 1
(1) WR(ALC = “1”): Enter ALC mode from Manual mode
(2) WR(ALC = “0”): Finish ALC mode and enter Manual mode
The IPGA becomes a value after finishing ALC operation. (In Figure 30, the IPGA value assumes
40H.)
(3) WR(IPGA=60H): If the written value to control register is the same as the current value, the written value is ignored,
therefore the IPGA value keeps 40H (the value after finishing the ALC operation).
Rev. 0.9
- 42 -
2000/09