User Manual

48 DS656F3
CS4245
occur after a time-out period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sam-
ple rate) if the signal does not encounter a zero crossing. The zero cross function is independently mon-
itored and implemented for each channel. See Table 16.
6.9.2 Analog Input Selection (Bits 2:0)
Function:
These bits are used to select the input source for the PGA and ADC. Please see Table 17.
6.10 DAC Channel A Volume Control - Address 0Ah
See 6.11 DAC Channel B Volume Control - Address 0Bh.
6.11 DAC Channel B Volume Control - Address 0Bh
6.11.1 Volume Control (Bits 7:0)
Function:
The digital volume control allows the user to attenuate the signal in 0.5 dB increments from 0 to -127 dB.
The Vol0 bit activates a 0.5 dB attenuation when set, and no attenuation when cleared. The Vol[7:1] bits
activate attenuation equal to their decimal equivalent (in dB). Example volume settings are decoded as
PGASoft PGAZeroCross Mode
0 0 Changes to affect immediately
0 1 Zero Cross enabled
1 0 Soft Ramp enabled
1 1 Soft Ramp and Zero Cross enabled (default)
Table 16. PGA Soft Cross or Zero Cross Mode Selection
Sel2 Sel1 Sel0 PGA/ADC Input
0 0 0 Microphone-Level Inputs (+32 dB Gain Enabled)
0 0 1 Line-Level Input Pair 1
0 1 0 Line-Level Input Pair 2
0 1 1 Line-Level Input Pair 3
1 0 0 Line-Level Input Pair 4
1 0 1 Line-Level Input Pair 5
1 1 0 Line-Level Input Pair 6
1 1 1 Reserved
Table 17. Analog Input Multiplexer Selection
76543210
Vol7 Vol6 Vol5 Vol4 Vol3 Vol2 Vol1 Vol0