Crystal Selection
Exact 12.288MHz crystal is not available in the nearby market.
Can I use a 12.000MHz crystal. Since I am using only the analog input and outputs... it wouldn't matter if the sampling frequency is not exactly 48KHz.
Also would it be ok if I use a 22pF load capacitance crystal.
Also should I change the PLL component values?
crystal
Yes, a 12 MHz crystal will work. You will have to remember that because your sampling frequency will scale, the center frequency of all of your filters will scale, as well. For example, a 12 MHz crystal will give you an fs that's 0.977 times the fs with a 12.288 MHz crystal. So, your new fs will be 46.875 kHz. If you change the master clock and fs rate, but use the same filter coefficients, then the center frequency of your filter will be off by the same ratio.
The PLL filter component values do not need to change for a small variation in sampling frequency like this. They are valid for a wide range of clock frequencies.
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