CS42325 Datasheet, PDF (28/71 Pages) Cirrus Logic – 10-In, 6-Out, 2 Vrms Audio CODEC with Headphone

4. APPLICATIONS
CS42325
4.1 System Clocking
The CS42325 will operate at sampling frequencies from 4 kHz to 108 kHz. This range is divided into two
speed modes as shown in Table 2.
Speed Mode
Single-Speed
Double-Speed
Master Mode Sampling
Frequency
4-54 kHz
50-108 kHz
Slave Mode
Sampling Frequency
4-54 kHz
50-108 kHz
Table 2. Speed Modes
The CS42325 has two serial ports which can operate synchronously or asynchronously. Serial Port 1
(SP1) consists of the SCLK1 and LRCK1 signals. Serial Port 2 (SP2) consists of the SCLK2 and LRCK2
signals. The serial audio output, SDOUT, and serial audio inputs, SDIN1 and SDIN2, can be independent-
ly assigned to either of the two serial ports for ease of clocking. Each serial port may be independently
placed into Single- or Double-Speed Mode. The serial ports may also be independently placed into Master
or Slave Mode.
4.1.1
Master Clock
In both Synchronous and Asynchronous Modes, MCLKx (MCLK1 and/or MCLK2) and the corresponding
LRCKx must maintain an integer ratio. Some common ratios are shown in Tables 3 and 4. The LRCKx
frequency is equal to Fs, the frequency at which audio samples for each channel are clocked into or out
of the device. The SP1_SPEED and SP2_SPEED bits and the MCLKx FREQ bits configure the device to
generate the proper clocks in Master Mode and receive the proper clocks in Slave Mode when auto detect
mode is disabled. Tables 3 and 4 illustrate several standard audio sample rates and the required MCLKx
and LRCKx frequencies.
Mode
SINGLE SPEED
MODE (SSM)
MCLKx FREQ [1:0]
MDIV pin
LRCKx
(kHz)
32
44.1
48
128x
-
-
-
-
-
192x
-
-
-
-
-
MCLKx (MHz)
256x
384x
8.1920
12.2880
11.2896 16.9344
12.2880 18.4320
00
01
0
-
512x
16.3840
22.5792
24.5760
10
1
768x
24.5760
33.8680
36.8640
11
-
Table 3. Single-Speed Mode Common Clock Frequencies
Mode
DOUBLE SPEED
MODE (DSM)
MCLKx FREQ [1:0]
MDIV pin
LRCKx
(kHz)
64
88.2
96
128x
8.1920
11.2896
12.2880
00
0
192x
12.2880
16.9344
18.4320
01
-
MCLKx (MHz)
256x
384x
16.3840 24.5760
22.5792 33.8680
24.5760 36.8640
10
11
1
-
512x
-
-
-
-
-
Table 4. Double-Speed Mode Common Clock Frequencies
768x
-
-
-
-
-
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