CS4362A Datasheet, PDF (36/47 Pages) Cirrus Logic – 114 dB, 192 kHz 6-channel D/A Converter

5.3 Filter Control (address 04h)
7
Reserved
0
6
Reserved
0
5
Reserved
0
4
FILT_SEL
0
3
Reserved
0
2
DEM1
0
CS4362A
1
DEM0
0
0
RMP_DN
0
5.3.1 Interpolation Filter Select (FILT_SEL)
Default = 0
0 - Fast roll-off
1 - Slow roll-off
Function:
This function allows the user to select whether the interpolation filter has a fast or slow roll off. For filter
characteristics please see Section 2.
5.3.2 De-Emphasis Control (DEM)
Default = 00
00 - Disabled
01 - 44.1 kHz
10 - 48 kHz
11 - 32 kHz
Function:
Selects the appropriate digital filter to maintain the standard 15 µs/50 µs digital de-emphasis filter response
at 32, 44.1 or 48 kHz sample rates. (see Figure 13)
De-emphasis is only available in Single Speed Mode.
5.3.3 Soft Ramp-Down before Filter Mode Change (RMP_DN)
Default = 0
0 - Disabled
1 - Enabled
Function:
If either the FILT_SEL or DEM bits are changed the DAC will stop conversion for a period of time to change
filter values. This bit selects how the data is effected prior to and after the change of the filter values. When
this bit is enabled the DAC will ramp down the volume prior to a filter mode change and ramp from mute to
the original volume value after a filter mode change according to the settings of the Soft and Zero Cross
bits in the Mode Control 3 register. When disabled, an immediate mute and unmute is performed.
Loss of clocks or a change in the FM bits will always cause an immediate mute; Unmute in these conditions
is affected by the RMP_UP bit.
Notes: For best results, it is recommended that this feature be used in conjunction with the RMP_UP bit.
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