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Do Altera Cyclone III FPGAs have an internal oscillator?

Altera_Forum
Honored Contributor II
‎04-20-2009 09:29 PM
1,436 Views

I am new to this. 

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? 

 

Thanks
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Altera_Forum
Honored Contributor II
‎04-20-2009 11:42 PM
670 Views

Hi, 

 

The CIII 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.
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