CS4351
6.5
Channel A Volume Control - Register 05h
Channel B Volume Control - Register 06h
7
VOL7
0
6
VOL6
0
5
VOL5
0
4
VOL4
0
3
VOL3
0
2
VOL2
0
1
VOL1
0
0
VOL0
0
6.5.1 DIGITAL VOLUME CONTROL (VOL7:0) BITS 7-0
Default = 00h (0 dB)
Function:
The Digital Volume Control registers allow independent control of the signal levels in 1/2 dB increments
from 0 to -127.5 dB. Volume settings are decoded as shown in Table 10. The volume changes are im-
plemented as dictated by the Soft and Zero Cross bits in the Power and Muting Control register.
The actual attenuation is determined by taking the decimal value of the volume register and multiplying
by 6.02/12.
Binary Code
00000000
00000001
00000110
11111111
Decimal Value
Volume Setting
0 dB
0
1
6
-0.5 dB
-3.0 dB
-127.5 dB
255
Table 10. Example Digital Volume Settings
6.6
Ramp and Filter Control - Register 07h
7
SZC1
1
6
SZC0
0
5
RMP_UP
1
4
RMP_DN
1
3
Reserved
0
2
FILT_SEL
0
1
Reserved
0
0
Reserved
1
6.6.1 SOFT RAMP AND ZERO CROSS CONTROL (SZC1:0) BITS 7-6
Default = 10
SZC1 SZC0
Description
Immediate Change
Zero Cross
0
0
1
1
0
1
0
1
Soft Ramp
Soft Ramp on Zero Crossings
Function:
Immediate Change
When Immediate Change is selected all level changes will take effect immediately in one step.
Zero Cross
Zero Cross Enable dictates that signal level changes, either by attenuation changes or muting, will occur
on a signal zero crossing to minimize audible artifacts. The requested level change will occur after a time-
out period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sample rate) if the signal
32
DS566PP2
CIRRUS [ CIRRUS LOGIC ]
