Based on the CDCE6214 datasheet, the Expected Output Frequency (FOUT) value is 24.576 MHz. What is the formula to calculate the value?
Are you referring to table 8?
In the description "PSA = 4, IOD = 25" -- And the equation is "FVCO = PSA × IOD × FOUT."
So the VCO frequency is 4 * 25 * 24.756 MHz = 2457.6 MHz.
And the output frequency can be solved as = FVCO / PSA / IOD.
The VCO frequency can be calculated from the reference frequency using:
VCO = xxxREF / PLL_R * (PLL_N + PLL_num / PLL_den)
If the doubler is used then:
VCO = xxxREF * 2 * (PLL_N + PLL_num / PLL_den)
In this example they don't give us the (PRI|SEC)REF input frequency. But they state their phase detector frequency is 25 MHz. 25 MHz could be the reference frequency with PLL R = 1.
VCO = 25 MHz / 1 * (98 + 152000 / 500000)
Hopefully this gives you an idea of the equations used for the PLL.
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