What this QDR II SRAM does in the system
It organizes as 512K x 36, so each access grabs a full 36-bit word, which maps cleanly to a 32-bit data bus plus parity or ECC overhead. The 250 MHz clock means the memory delivers back-to-back read and write transactions on every rising and falling edge, no dead cycles between bus turnarounds. That matters when you are trying to sustain line-rate forwarding in a 10 GbE or 40 GbE design without stalling the pipeline.
Supply rails and temperature — the fit check
No separate I/O voltage is listed in the record — the QDR II interface itself operates at the same 1.8 V nominal level. If the BOM calls for extended temperature, you would step up to the I-grade variant of this family.
Package reality for layout
The package is a 165-ball FBGA, 13x15 mm body — a fine-pitch BGA that needs a multi-layer PCB with microvias or at least a tight via-in-pad strategy for the center balls. The 250 MHz clock rate means signal integrity on the data and address lines is not optional: controlled impedance traces, matched lengths within the byte lanes, and enough decoupling capacitance within 5 mm of each supply ball. The 1.8 V core is low enough that IR drop across the BGA array matters less than the return-current path through the ground plane. If you are laying out a board that already carries a Virtex or Stratix-class FPGA, the FBGA footprint and routing discipline will feel familiar.