Cirrus Logic CS4270 - Manual (Page 37)

DS686F1 37
CS4270
8.8 DAC Channel B Volume Control - Address 08h
Function:
The digital volume control allows the user to attenuate the signal in 0.5 dB increments from 0 to -127 dB.
VOL0 activates a 0.5 dB attenuation when set, and no attenuation when cleared. VOL[7:0] activates at-
tenuation equal to their decimal value (in dB). Example volume settings are decoded as shown in
Table 14 . The volume changes are implemented as dictated by the DAC_SOFT and DAC_ZC bits in the
Transition Control register (see Section 8.5.2 ).
7 6 5 4 3 2 1 0
DACB
VOL7
DACB
VOL6
DACB
VOL5
DACB
VOL4
DACB
VOL3
DACB
VOL2
DACB
VOL1
DACB
VOL0
Binary Code Volume Setting
00000000 0 dB
00000001 -0.5 dB
00101000 -20 dB
00101001 -20.5 dB
11111110 -127 dB
11111111 -127.5 dB
Table 14. Digital Volume Control