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Altera_Forum
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8 years ago

Internal Oscillator for MAX10 device

Hello. I am trying to use internal oscillator in MAX10 FPGA. It works but I am getting 83 mhz instead of desired 55 mhz. Already confusing the frequency setting in IP altera_int_osc. It says C...
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Altera_Forum
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8 years ago

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You don't get a choice. The internal oscillator for the smaller MAX10 devices is spec'ed to be in the range of 55MHz to 116MHz, nominal 82MHz. Your oscillator is more or less on spec as typical at 83MHz.

If you need a repeatable, accurate frequency source, then you need to use an external source based on a crystal, and possibly feed it to a PLL internal to the MAX10.

The internal oscillator is provided as a 'freebie' but you don't get to choose the value, you only know is is between 55MHz and 116MHz, and may change widely over voltage and temperature.

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Hello

If it is so it is very bad news you provided.

Is there any doc which state that we cannot set this value?

Regarding PLL, "you cannot drive the plls with internal oscillator"

https://www.altera.com/en_us/pdfs/literature/hb/max-10/ug_m10_clkpll.pdf page 33

Anyway, thanks for the reply.