Cirrus Logic CS4382A - Manual (Page 35)

DS618F2 35
CS4382A
DSD Mode: The relationship between the oversampling ratio of the DSD audio data and the required
master clock-to-DSD-data-rate is defined by the Digital Interface Format pins.
6.3 Mode Control 3 (Address 03h)
6.3.1 Soft Ramp and Zero Cross Control (SZC)
Default = 10
00 - Immediate Change
01 - Zero Cross
10 - Soft Ramp
11 - 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
does not encounter a zero crossing. The zero cross function is independently monitored and implemented
for each channel.
Soft Ramp
Soft Ramp allows level changes, both muting and attenuation, to be implemented by incrementally ramp-
ing, in 1/8 dB steps, from the current level to the new level at a rate of 1 dB per 8 left/right clock periods.
Soft Ramp on Zero Crossing
Soft Ramp and Zero Cross Enable dictates 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.
DIF2 DIF1 DIFO DESCRIPTION
0 0 0 64x oversampled DSD data with a 4x MCLK to DSD data rate
0 0 1 64x oversampled DSD data with a 6x MCLK to DSD data rate
0 1 0 64x oversampled DSD data with a 8x MCLK to DSD data rate
0 1 1 64x oversampled DSD data with a 12x MCLK to DSD data rate
1 0 0 128x oversampled DSD data with a 2x MCLK to DSD data rate
1 0 1 128x oversampled DSD data with a 3x MCLK to DSD data rate
1 1 0 128x oversampled DSD data with a 4x MCLK to DSD data rate
1 1 1 128x oversampled DSD data with a 6x MCLK to DSD data rate
Table 6. Digital Interface Formats - DSD Mode
7 6 5 4 3 2 1 0
SZC1 SZC0 SNGLVOL RMP_UP MUTEC+/- AMUTE Reserved MUTEC
1 0 0 0 0 1 0 0