Intel® Quartus® Prime Software
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generate 24.5760 MHz with ALTPLL

Altera_Forum
Honored Contributor II
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Hi  

 

I'm using an Arria II GX FPGA and want to generate 24.576 MHz with the MegaWizard Function ALTPLL. The input frequency to the PLL is 125MHz. The output frequency is calculated with fout = fin * (M/N). N and M are integer variables from 0-512. It seems that it is not possible to create exactly 24.576 MHz (+- 50ppm) with ALTPLL. The 24.576MHz are used to clock an Analog Digital Converter. Are there other ways to create the needed clock frequency? 

 

Thanks for any help 

 

Christoph
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Altera_Forum
Honored Contributor II
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Nop. You'll have to get an external 24.5760 MHz clock.

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Altera_Forum
Honored Contributor II
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Thanks for your answer. I'will using the adc onboard oscillator.  

 

best regards
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