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Max input Voltage for single ended clock input (Stratix IV)

SHard2
Novice
311 Views

Hi

We have an existing board containing a EP4SE360F35I3 (F1152 PACKAGE). I am trying to determine the maximum input Voltage that can be safely be fed into a dedicated clock input pin (single ended). Specifically CLK8P and CLK10P. (CLK8P is bank 5C which is at 2.5V, CLK10P is bank 6C which is at 2.5V.)

 

The documentation states that a single-ended clock input should be treated as IO. In which case, from the table below (for a 2.5V Vccio) the maximum 'Vih' it can safely accept is 3.6V.

 

If you could confirm this for me it would be greatly appreciated?

 

Many thanks

Simon

 

Stratix_IV_SingleEnded_IO_Standards.png

 

 

 

 

 

 

 

 

0 Kudos
7 Replies
ShafiqY_Intel
Employee
190 Views

Hi Simon,

 

May I know which document/user guide you are referring? (table above)

Please provide me the link.

 

Thanks

SHard2
Novice
190 Views

Good morning

There seems to be a problem with the support system. I had already replied with this information but it did not appear in the support case.

The original support case has reference number 04561609, but the link in your email opens a different case without my replies in it.

Regards

Simon

 

 

**** Previous Email ****

Good morning and thank you for getting back to me.

The table was taken from the following document…

 

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/stratix-iv/stx4_siv54001...

 

Table 1-17 (Single-Ended I/O Standards) on page 1-12.

 

Best regards

Simon

SHard2
Novice
190 Views

 

​Good morning

I have not heard back from you and wondered if you were able to provide an answer.The table I included in the original post was taken from the following document...

ttps://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/stratix-iv/stx4_siv54001.pdf

Table 1-17 (Single-Ended I/O Standards) on page 1-12.

 

If you are able to advise it would be much appreciated.

Best regards

Simon

 

 

 

 

 

ShafiqY_Intel
Employee
190 Views

Hi Simon,

 

I'm apologize for late reply for this thread.

 

Yes, the User Guide you referring is the correct User Guide.

The recommended Vccio for I/O standard 2.5 V is (min 2.375, typical 2.5, max 2.625).

 

And if you are looking for input voltage, the table 1-17 is correct.

  • VIL = minimum -0.3V, maximum 0.7V
  • VIH = minimum 1.7V, maximum 3.6V

 

Thanks

SHard2
Novice
190 Views

​Hi,

Thanks you for getting back to me.

So just to confirm, we can safely feed a single ended clock signal (maximum 3.0V) into CLK8P and CLK10P?

(Both bank 5C and 6C use a Vccio of 2.5V.)

 

This should be safely within the ViH limit of 3.6V as shown in the table.

 

Best regards

Simon

 

 

 

 

 

 

 

 

ShafiqY_Intel
Employee
190 Views

Hi Simon,

 

Yes, you're right.

You can safely feed a single ended clock signal (maximum 3.0V) into CLK8P and CLK10P.

 

Thanks

SHard2
Novice
190 Views

​Hi

Thank you for confirming this for us.

That covers everything we need to know.

 

Best regards

Simon

 

 

 

 

 

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