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VCC_CLKIN on cyclone iv gx150

CNash2
Beginner
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If I have single ended CLK inputs 3.3V LVTTL in bank3a, b or 8a, b does it matter what voltage is applied to VCC_CLKIN.

 

I guess it only matters if one of those bank is using a differential input clock, when the pin must be set to 2.5v

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a_x_h_75
New Contributor III
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The threshold at which a clock edge is detected will be derived from VCC_CLKIN. So generally it will matter. However, in your case it shouldn't.

 

Cheers,

Alex

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CNash2
Beginner
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Thanks Alex..

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Rahul_S_Intel1
Employee
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Hi, The VCC_CLKIN is only used for bank 3 and 8 remaining not.Kindly find the page no:4 for the below document. https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/dp/cyclone-iv/pcg-01008.pdf For other banks no need to consider
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CNash2
Beginner
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I have 3.3v LVTTL clock signals on bank 3a, 3b and 8a, but differential clock input on 8b. So I will put 2.5V on Vcc_clkin8b but 3.3V on the others. Is this correct?

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Rahul_S_Intel1
Employee
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Yes others places which ever IO standard supports

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