CS42L50 Datasheet, PDF (25/48 Pages) Cirrus Logic – Low Voltage, Stereo CODEC with headphone Amp

CS42L50
4.2.8 Channel A Analog Headphone Attenuation Control (address 02h) (HVOLA)
4.2.9 Channel B Analog Headphone Attenuation Control (address 03h) (HVOLB)
7
HVOLx7
0
6
HVOLx6
0
5
HVOLx5
0
4
HVOLx4
0
3
HVOLx3
0
2
HVOLx2
0
1
HVOLx1
0
0
HVOLx0
0
Default = 0 dB (No attenuation)
Function:
The Analog Headphone Attenuation Control operates independently from the Digital Volume Control. The
Analog Headphone Attenuation Control registers allow attenuation of the headphone output signal for
each channel in 1 dB increments from 0 to -25 dB. Attenuation settings are decoded using a 2’s comple-
ment code, as shown in Table 1. The volume changes are implemented as dictated by the Soft and Zero
Cross bits in the Power and Muting Control register. All volume settings greater than zero are interpreted
as zero.
Note: The Analog Headphone Attenuation only affects the headphone outputs. When set for levels
greater than -10dB, the actual attenuation deviates from the register setting by more than 1 dB.
Binary Code
00000000
11110110
11110001
Decimal Value
0
-10
-15
Volume Setting
0 dB
-10 dB
-15 dB
Table 1. Example Analog Volume Settings
4.2.10 Channel A Digital Volume Control (address 04h) (DVOLA)
4.2.11 Channel B Digital Volume Control (address 05h) (DVOLB)
7
DVOLx7
0
6
DVOLx6
0
5
DVOLx5
0
4
DVOLx4
0
3
DVOLx3
0
2
DVOLx2
0
1
DVOLx1
0
0
DVOLx0
0
Default = 0 dB (No attenuation)
Function:
The Digital Volume Control registers allow independent control of the signal levels in 1 dB increments
from +18 to -96 dB. Volume settings are decoded using a 2’s complement code, as shown in Table 2.
The volume changes are implemented as dictated by the Soft and Zero Cross bits in the Power and Mut-
ing Control register. All volume settings less than -96 dB are equivalent to muting the channel via the
ATAPI bits (see Section 4.46).
Note: The digital volume control affects both the line outputs and the headphone outputs. Setting this
register to values greater than +18 dB will cause distortion in the audio outputs.
DS544PP1
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