07-29-2019 03:07 AM - edited 07-29-2019 03:10 AM
I want to know a V_IH of Filp Flop in CARRY4 SLICE. (Spartan6 SP605, in reference to Datasheet DS162)
Please tell me what type it is.
Also, tell me how to check this type. and Can I think of VIH as a Threshold Voltage for that device? Thank you.
07-30-2019 02:51 AM
The Carry 4 slice does not have an IO standard as it is internal to the FPGA. It runs on the core voltage (Vint) of the device. The IO buffers translate the signals on the pins to the internal voltage.
07-31-2019 05:38 AM
I expect that's confidential Xilinx information.
Unless you've actually decapsulated the chip and managed to get a tiny probe right onto the FDCE clock input, it's irrelevant - because there's no way to directly access that pin from outside the chip.
07-31-2019 05:47 AM
You say port,
do you mean an IO pin ?
its only IO pins on the package that have IO stadards ( as it says on the tin )
If you have conected this FF to a pin, then its in the pin voltage section, as defined in your constraints file.
if you have not connected the FF to an IO, then it has no IO voltage .
what tool ar eyou using to desing the part ?
vivado ? ISE ? which version ?