09-20-2013 06:38 AM
We are planning to interface 2 No.s of Micron’s MT41J256M16HA-093:E DDR-3 Memories to the Zynq processor. As I see, this part number is not readily available under the drop down menu of "Memory Interface(DDR2/3, LPDDR2 controller)" of Zynq 7000, we need to define it as a custom DDR-3 device.
The selected DDR-3 device is of speed grade 93(2133 MT/s) and speed grade supported by Zynq is only 187(1066MT/s). When we choose to customize this part in the Zynq Memory Interface tab we are seeing that the maximum operating frequency achievable is 533.333333MHz. If we decide to operate the above mentioned part at 533.333333 MHz then parameters like CAS Latency, CAS Write Latency, RAS to CAS delay, Precharge Time should be chosen from which Speed Bins table from the data sheet? Should it be chosen from “DDR3-1066” Speed Bins having speed grade (-187E/187) with the Operating Frequency 533.333333 MHz or should we choose the parameters from “DDR3-2133” Speed Bins having speed grade as (-093)? Kindly confirm.
09-20-2013 09:09 AM
You mean DDR3 interface in PS or or PL like any other device ?
So for custom part you can change the timing parameters from your target device (DDR3-2133) datasheet but the memory operating frequency range is based on the base part only!
Do you use Vivado MIG IP catalogue/IPI ?
09-21-2013 12:37 PM
Its DDR3 interface in PS using ISE toolflow .
From the reply below can i infer that "If we decide to operate the above mentioned part at 533.333333 MHz then parameters like CAS Latency, CAS Write Latency, RAS to CAS delay, Precharge Time can be chosen from Data sheet of (DDR3-2133) but the memory operating frequency range is based on the base part only! which is 533 .33 MHZ.
09-21-2013 06:57 PM
Yes, this is because if you select a base part speed grade say -n1, the custom part wizard timing parameters will allow you only to a certain range, so ideally you cannot create a part which is -(n1+3), in case if it allows you may tweak them to achieve -(n1+1).
Again custom part is somthing which is not characterized by MIG, so you may have to run simulations and verify the behavour.
Hope this clarifies.