CS4271 Datasheet, PDF (41/53 Pages) Cirrus Logic – 24-Bit, 192 kHz Stereo Audio CODEC

CS4271
itored and implemented for each channel. See Table 14 on page 41.
Soft Ramp and Zero Cross Enable
Soft Ramp and Zero Cross Enable dictate that signal level changes, either by attenuation changes or
muting, will occur in 1/8 dB steps and be implemented on a signal zero crossing. The 1/8 dB 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 does not encounter a zero crossing. The zero cross function is
independently monitored and implemented for each channel. See Table 14 on page 41.
Table 14. Soft Cross or Zero Cross Mode Selection
Soft
ZeroCross
Mode
0
0
Changes to affect immediately
0
1
Zero Cross enabled
1
0
Soft Ramp enabled (default)
1
1
Soft Ramp and Zero Cross enabled
8.3.3 ATAPI Channel Mixing and Muting (Bits 3:0)
Function:
The CS4271 implements the channel mixing functions of the ATAPI CD-ROM specification. See
Table 15 on page 42
Left Channel
Audio Data
A Channel
Volume
Control
AoutA
Σ
Right Channel
Audio Data
B Channel
Volume
Control
Figure 20. ATAPI Block Diagram
AoutB
DS592F1
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