It uses a parallel memory interface and is packaged in a 165-FBGA (13x15 mm) footprint. This is a high-bandwidth, low-latency memory part originally designed for networking equipment — think switch fabric buffers, router lookup tables, and telecom line-card packet memory — where the DDR II interface doubles the data rate without doubling the bus clock.
250 MHz clock — what it buys the system
At 250 MHz, the DDR II interface delivers a 500 MT/s data rate on a 36-bit-wide bus. That is enough bandwidth to feed a 10 GbE lookup engine or a mid-range packet processor without stalling. The 1M x 36 depth gives you 4 MB of working space — enough for a few thousand IPv4 route entries or a moderate packet buffer. If your design needs more depth, you would be looking at the 72 Mbit or 144 Mbit variants in this family, but the footprint changes.
The 165-ball FBGA measures 13x15 mm with a fine-pitch ball array. This is not a hand-solderable part — you need a rework station with a bottom heater and a stencil for the BGA. It is not rated for the thermal cycling of an outdoor base station or an engine bay. If the board lives in a conditioned space, the temp range is fine.
The CY7C1424KV18-250BZCT is officially marked obsolete. Cypress (now part of Infineon) no longer manufactures this specific speed and package variant. There is no direct pin-compatible replacement listed in the official records — the DDR II SRAM family has largely been superseded by QDR and RLDRAM architectures in new designs.