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Cyclone V - LVDS input on a bank with Vccpd=2.5V and Vccio=1.8V

Zak
New Contributor I
553 Views

Hello,

I'd like to have a confirmation of what I found on the Cyclone V Device Handbook regarding mixed voltage standards on a single bank.

In my design I have multiple I/Os @ 1.8V and LVDS inputs on the same bank. Quartus doesn't issue any errors and the project compiles and fits successfully. I've done this because on the Handbook (Table 5-9: Cyclone V I/O Standards Voltage Levels) it's specified that LVDS inputs are only dependent to Vccpd, which is equal to 2.5V on my bank. There's also a note which says: "Input buffers for the SSTL, HSTL, Differential SSTL, Differential HSTL, LVDS, RSDS, Mini-LVDS, LVPECL, HSUL, and Differential HSUL are powered by VCCPD".

Can someone confirm that?
Thank you

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1 Solution
ShafiqY_Intel
Employee
540 Views

Hi Zak,

 

There is no issue to use mixed voltage standards on a single bank. As long as that particular I/O bank supported your I/O standard (Vccpd=2.5V and Vccio=1.8V)

 

Regards,

Matt

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3 Replies
ShafiqY_Intel
Employee
541 Views

Hi Zak,

 

There is no issue to use mixed voltage standards on a single bank. As long as that particular I/O bank supported your I/O standard (Vccpd=2.5V and Vccio=1.8V)

 

Regards,

Matt

Zak
New Contributor I
532 Views

Hi Matt,

I know that there is no issue to use mixed voltage standards on a single bank. What I don't understand is if I can do it with LVDS inputs, since the Vccio requirements in Table 5-9 of the Device Handbook for LVDS inputs is not so clear.

For LVDS outputs the requirements are Vccpd=2.5V and Vccio=2.5V.

For LVDS inputs the requirements are Vccpd=2.5V and Vccio=? Is it not relevant since only Vccpd is used for input LVDS buffers?

Thank you

ShafiqY_Intel
Employee
467 Views

Hi Zak,

 

For LVDS inputs the requirements is Vccio=Vccpd

For LVDS outputs the requirements is Vccio=2.5V

 

And for Cyclone V, the value for Vccpd is 2.5V

 

Regards,

Matt

 

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