User guide

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).
76543210
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