User guide

CS4392
10 DS459PP3
3.4 Interpolation Filter
To accommodate the increasingly complex requirements of digital audio systems, the CS4392 incorpo-
rates selectable interpolation filters for each mode of operation. A fast and a slow roll-off filter is available
in each of Single, Double, and Quad Speed modes. These filters have been designed to accommodate a
variety of musical tastes and styles. Bit 5 of the Mode Control 3 register (06h) is used to select which filter
is used. Filter specifications can be found in Section 8, and filter response plots can be found in Figures 12
to 35.
In stand-alone mode, only the fast roll-off filter is available.
3.5 System Clocking
The required MCLK to LRCK and suggested SCLK to LRCK ratios are outlined in table 1. MCLK can be
at any phase in regards to LRCK and SCLK. SCLK, LRCK and SDATA must meet the phase and timing
relationships outlined in Section 7. Some common MCLK frequencies have been outlined in tables 2 to 4.
*Note:These clocking ratios are only available in Control Port Mode when the MCLK Divide bit is enabled.
MCLK/LRCK SCLK/LRCK LRCK
Single Speed 256, 384, 512, 768, 1024* 32, 48, 64, 96, 128 Fs
Double Speed 128, 192, 256, 384, 512* 32, 48, 64 Fs
Quad Speed
64 32 (16 bits only) Fs
96 32, 48 Fs
128, 256* 32, 64 Fs
192 32, 48, 64, 96 Fs
Table 1. Clock Ratios
Sample Rate
(kHz)
MCLK (MHz) See Note
256x 384x 512x 768x 1024x*
32 8.1920 12.2880 16.3840 24.5760 32.7680
44.1 11.2896 16.9344 22.5792 33.8688 45.1584
48 12.2880 18.4320 24.5760 36.8640 49.1520
Table 2. Single Speed (4 to 50 kHz sample rates) Common Clock Frequencies
Sample Rate
(kHz)
MCLK (MHz) See Note
128x 192x 256x 384x 512x*
64 8.1920 12.2880 16.3840 24.5760 32.7680
88.2 11.2896 16.9344 22.5792 33.8688 45.1584
96 12.2880 18.4320 24.5760 36.8640 49.1520
Table 3. Double Speed (50 to 100 kHz sample rates) Common Clock Frequencies
Sample Rate
(kHz)
MCLK (MHz) See Note
64x 96x 128x 192x 256x*
176.4 11.2896 16.9344 22.5792 33.8688 45.1584
192 12.2880 18.4320 24.5760 36.8640 49.1520
Table 4. Quad Speed (100 to 200 kHz sample rates) Common Clock Frequencies