36Mbit DDR II+ SRAM at 450 MHz — the buffer workhorse
The Cypress CY7C1250KV18-450BZXC is a 36Mbit synchronous SRAM built on the DDR II+ architecture, clocked at 450 MHz. Organized as 1M x 36, it delivers back-to-back read/write transactions without dead cycles on the parallel bus — the DDR II+ interface eliminates the turnaround penalty that standard QDR or NoBL parts incur.
At 450 MHz, the DDR II+ interface transfers data on both clock edges, so the effective data rate is 900 MT/s per pin. The 36-bit-wide data bus delivers a theoretical peak of 32.4 Gbps. That kind of edge rate demands careful signal-integrity work on the PCB — trace impedance control, matched lengths, and a solid reference plane under the 165-ball LBGA.
If your system sees -40°C startup or 85°C internal air, this is the wrong temperature grade — look for the industrial or extended-range variant in the CY7C1250KV18 family.
Cypress (now part of Infineon) no longer manufactures this exact order code. For BOM lines that still specify this device, procurement must go through the independent distribution channel — surplus inventory, new-old-stock, or broker-sourced material.