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Altera_Forum
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11 years ago

[CPLD MAX 10] Connecting the internal oscillator clock to the input of PLL

Hello, So I wish to utilise the internal oscillator of the CPLD MAX10 as the clock source in my system. The minimum clock frequency that the oscillator can output is 55MHz (it's a 10M08), wh...
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Altera_Forum
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11 years ago

in the "MAX 10 Clocking and PLL User Guide"

section 3-2 "Internal Oscillator Design Considerations"

"You cannot drive the PLLs with internal oscillator."

i think that is the reason.

integrate a oscillator in a fpga is a great progress, but if it can not be connected to a pll, the internal oscillator can not be used in most case.

i do not know why