What would happen if VCCPD is less than VCCIO?

[AThai8]

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?

[YuanLi_S_Intel]

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]

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]

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