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Do Altera Cyclone III FPGAs have an internal oscillator?

bluesea

I would like to use if Altera Cyclone III FPGAs have an internal clock (oscillator) that I can use. Or am I required to use an external clock input?image

  • Hi,

     

    The Cyclone III fpga is designed to use a external clock source. The internal clock source OSC mentioned in the literature is not available to the user design only for internal startup operations of the FPGA. Technically you can create a ring oscillator with inverters as a hack, but the quality of clock would not controlled compared to using a external clock chip which has clear timing specifications.

     

    You might also like to join http://www.alterauserforums.org

     

    Just wondering what is the application that you will be designing ?

     

    Cheers,

     

    Edmund.

  • Yes! You can use it in your design, or you can route it outside. Just use an IP: Basic Functions -> Configuration and Programming -> Internal Oscillator

    It uses altera_int_osc megafunction