10-10-2018 10:43 AM
I just need to basically interface to a DDR3 memory and a parallel ADC.
I am looking at A35T or A50T for logic count.
Which package is the easiest to work with in term or pcb layout or other complexity ?
10-10-2018 11:08 AM - edited 10-10-2018 11:22 AM
Depends on what your definition of easiest but usually for a BGA it centers around the pitch size. The finer the pitch the less room you have for signal routing between the BGA balls. Also I am not sure why you are not considering or looking at the spartan-7 equivalents. They have about the same logic, can support DDR3 and contains an ADC but due to not having any transceivers are considerably cheaper. If you were to go spartan-7 I'd recommend the FTBG196 or CSGA324 depending on if how many IOs you need as well as if you can tolerate the 0.8mm finer pitch on the CSGA than the standard 1.0mm on the FTBG. The nice thing about these two packages are that they come in both the 25T and the 50T die densities so if 25T turns out is not enough logic you can just get a 50T in the same package and still use the same board.
For Artix, I would say the same as above for the CSG325 except there is also a 35T density as well and the CSG325 is compatible with all three 25T/35T/50T. There is also a couple other packages as well that are compatible between only 35T and 50T but CSG325 gives you the most flexibility if that is important to you. One thing to note again here is it is 0.8mm pitch...
Finally I would recommend looking through the below links to help you understand more about 7-series product offerings and guidelines on Xilinx BGA layout.