CS4351
4. APPLICATIONS
4.1 Sample Rate Range/Operational Mode Detect
The device operates in one of three operational modes. The allowed sample rate range in each mode will
depend on whether the Auto-Detect Defeat bit is enabled/disabled.
4.1.1 Auto-Detect Enabled
The Auto-Detect feature is enabled by default. In this state, the CS4351 will auto-detect the correct
mode when the input sample rate (F ), defined by the LRCK frequency, falls within one of the rang-
s
es illustrated in Table 2. Sample rates outside the specified range for each mode are not supported.
Input Sample Rate (F )
MODE
S
4 kHz - 50 kHz
84 kHz - 100 kHz
170 kHz - 200 kHz
Single Speed Mode
Double Speed Mode
Quad Speed Mode
Table 2. CS4351 Auto-Detect
4.1.2 Auto-Detect Disabled
The Auto-Detect feature can be defeated only by the format bits in the control port register 02h. In
this state, the CS4351 will not auto-detect the correct mode based on the input sample rate (F ). The
s
operational mode must then be set manually according to one of the ranges illustrated in Table 3.
Please refer to section 6.2.3 for implementation details. Sample rates outside the specified range
for each mode are not supported. In stand-alone mode it is not possible to disable auto-detect of
sample rates.
FM1
FM0
Input Sample Rate (F )
MODE
S
0
0
1
1
0
1
0
1
Auto speed mode detect
4 kHz - 50 kHz
50 kHz - 100 kHz
100 kHz - 200 kHz
Auto
Single Speed Mode
Double Speed Mode
Quad Speed Mode
Table 3. CS4351 Mode Select
16
DS566PP2
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