alc885-gr Realtek Semiconductor Corporation, alc885-gr Datasheet - Page 95

• Manufacturer Part Number: alc885-gr
• Description: 7.1+2 Channel High-performance Hda Codec With Content Protection
• Manufacturer: Realtek Semiconductor Corporation

11.2.2.
A 5-bit resolution ADC operating at 64*SYNC clock rate is used to converts the DC level on VAR into 32
steps for the Volume knob. Hardware will not directly change the volume, the DC level change will be
reflected to software by unsolicited response in every 64 SYNC(=64*20.84usec)
7.1+2 Channel High-Performance HDA Codec
With Content Protection
92.0%< DC <= 95.0%
89.0%< DC <= 92.0%
86.0%< DC <= 89.0%
83.0%< DC <= 86.0%
80.0%< DC <= 83.0%
77.0%< DC <= 80.0%
74.0%< DC <= 77.0%
95.0%=< DC
Input DC
Voltage
Volume Control by External Variable Resistor
Volume
Code
1D
1C
1B
1A
1F
1E
19
18
Table 95. Volume Code Corresponding to DC Level at Pin 33
Figure 23. Volume Control by External Variable Resistor
71.0%< DC <= 74.0%
68.0%< DC <= 71.0%
65.0%< DC <= 68.0%
62.0%< DC <= 65.0%
59.0%< DC <= 62.0%
56.0%< DC <= 59.0%
53.0%< DC <= 56.0%
50.0%< DC <= 53.0%
Input DC
Voltage
Volume
Code
17
16
15
14
13
12
11
10
87
47.0%< DC <= 50.0%
44.0%< DC <= 47.0%
41.0%< DC <= 44.0%
38.0%< DC <= 41.0%
35.0%< DC <= 38.0%
32.0%< DC <= 35.0%
29.0%< DC <= 32.0%
26.0%< DC <= 29.0%
Input DC
Voltage
Volume
Code
0D
0C
0B
0A
0F
0E
09
08
23.0%< DC <= 26.0%
20.0%< DC <= 23.0%
17.0%< DC <= 20.0%
14.0%< DC <= 17.0%
11.0%< DC <= 14.0%
8.0%< DC <= 11.0%
5.0%< DC <= 8.0%
DC <= 5.0%
Input DC
Voltage
ALC885 Series
Datasheet
Volume
Code
Rev. 1.1
07
06
05
04
03
02
01
00