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Altera_Forum
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16 years ago

Cyclone III Clock

Hi Dear all I am new in this forume and also FPGA projects I want to use one of the cyclone III FPGAs in my project (EP3C80 probebly 8N) and I want to make sure what is the clock frequency inpu...
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Altera_Forum
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16 years ago

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do I need to connect all CLK0 to CLK15 pins to input clock source

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Surely not all of them. If your application probably requires multiple PLLs, you may want to provide a direct clock input to each of the four PLLs for optimal performance, e.g. CLK0,4,8,12. But Cyclone III has also an option to use a global clock source as PLL input, so if clock jitter isn't that critical, a single clock input can supply all PLLs.