Intel® Quartus® Prime Software
Intel® Quartus® Prime Design Software, Design Entry, Synthesis, Simulation, Verification, Timing Analysis, System Design (Platform Designer, formerly Qsys)
Announcements
Intel Support hours are Monday-Fridays, 8am-5pm PST, except Holidays. Thanks to our community members who provide support during our down time or before we get to your questions. We appreciate you!

Need Forum Guidance? Click here
Search our FPGA Knowledge Articles here.
15331 Discussions

What would happen if VCCPD is less than VCCIO?

AThai8
Beginner
239 Views

Hi, I am using the Cyclone V GT. What would happen if my VCCPD is 2.5V and VCCIO is 3.3V for the same bank?

0 Kudos
3 Replies
YuanLi_S_Intel
Employee
149 Views

Hi AN Thai,

 

There is no problem as both power rail are different. Supplying different VCCPD and VCCIO is depending on the I/O standard that you are going to use. You may refer to device user guide for more information about it.

 

Thank You.

AThai8
Beginner
149 Views

Hi,

 

Thank you for the response.

 

Please allow me to elaborate a bit further. Based on the data sheet VCCPD must be 3.3V when VCCIO is 3.3V and must be 2.5V when VCCIO is less than or equal to 2.5V. I have an adjustable VCCIO between 1.2V and 3.3V, my question is as my VCCIO varies, can VCCPD stays at 2.5V? Or should I switch VCCPD between 2.5V and 3.3V as VCCIO changes?

 

Thank you.

YuanLi_S_Intel
Employee
149 Views

Hi AN Thai,

 

First of all, the VCCIO shouldnt be changing. It must be fixed at all the time. Thus, it is not appropriate for the method.

 

Thank You

Reply