ak4560a AKM Semiconductor, Inc., ak4560a Datasheet - Page 31

• Manufacturer Part Number: ak4560a
• Description: 16bit Codec With Alc And Mic/hp/spk-amps
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
[AK4560A]
n Analog Volume (OPGA)
The AK4560A includes the 0dB
-50dB & MUTE analog volume with zero crossing detection for headphone and
speaker. Zero crossing is detected on L/R channels independently. Zero crossing timeout (To) is proportional to sampling
rate. To=512/fs@fs=48kHz=10.7ms.
OPGA is not written during counting zero crossing timers. In case of writing control register continually, the change of
OPGA should be written after zero crossing timeout and over. If OPGA is changed by writing to control register before
zero crossing detection, OPGA value of L/R channels may not give a difference level.
Usually, to remove the offset of DAC, it needs a capacitor (Ca) between LOUT2/ROUT2 and OPGL/OPGR. The cut-off
frequency is decided by capacity of Ca and input impedance (typ. 110k ) of OPGL/OPGR.
Power supply for analog volume enables when speaker or headphone of power management bits is “1”. (SPKP bit = “1”
or HPP bit = “1”)
The initial value is 0dB at exiting power-down.
LOUT2/ROUT2
Ca
typ.110k
OPGA
OPGL/OPGR
Figure 17. Connect LOUT2/ROUT2 with OPGL/OPGR
n LINE input
In case of LINE input, input impedance of LIN/RIN is 184k (typ.) and centered around the VCOM voltage. When input
voltage is +2dBV, LIN/RIN pins should be input to –5.5dBV@VA=2.8V and less after dividing resistors externally.
When LIN bit is “1”, LINE input is selected. Then IPGA table of ALC1 is changed to LINE side.
ALC1
LIN/RIN
27k
LINE input
typ.184k
22k
Figure 18. Example of LINEIN at VA=2.8V
MS0028-E-00
2000/05
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