ak4561 AKM Semiconductor, Inc., ak4561 Datasheet - Page 36

• Manufacturer Part Number: ak4561
• Description: 16bit Codec With Built-in Alc And Mic/hp-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
n Headphone Amplifiers
The output circuit of headphone amplifier does not need a capacitor to cancel DC because the headphone amplifier
includes center amplifier (HVCM). Load impedance of headphone amplifier is minimum 55 .
The output signals are muted when S8 bit is “0”, the headphone amplifiers become Power-Save-Mode. Then HPL/HPR
pin go Hi-z and HVCM pin is output to VCOM voltage. (Refer to Figure 23)
When PM5 bit is “0”, the headphone amplifiers can be powered-up completely. Then HPL/HPR pins become Hi-z and
HVCM pin becomes “L” (AGND). (Refer to Figure 24)
When PD pin changes from “L” to “H” after power-up, the output signals from headphone amplifier is muted, the
headphone amplifiers are powered-up by Power-Save-Mode. After that, S8 bit should be changed into “0” before
headphone amplifier is done by the normal operation.
Rev. 0.9
Figure 24. Headphone-Amps Power-Down-Mode
Figure 23. Headphone-Amps Power-Save-Mode
Figure 22. Headphone-Amps Normal Operation
AKM CONFIDENTIAL
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PM5
PM5
PM5
S8
S8
S8
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HPL/HPR
HPL/HPR
HPL/HPR
HVCM
HVCM
HVCM
[AK4561]
2000/09