450 MHz DDR II+ — what it buys you
The CY7C11681KV18-450BZC is a 18Mbit synchronous SRAM from Infineon (originally Cypress) using the DDR II+ architecture. It clocks at 450 MHz, delivering two data transfers per clock cycle on a 1M x 18 organisation. The parallel interface and 1.7V to 1.9V core supply target high-bandwidth buffer applications — think network switch packet memory, telecom line-card look-up tables, or cache for DSP arrays where every nanosecond of access latency matters.
Obsolete — sourcing path
Infineon lists the CY7C11681KV18-450BZC as Obsolete. That means the factory line is shut; no new production runs are planned. For a BOM that still calls out this exact order code, the supply route goes through independent distribution — surplus stock, last-time-buy leftovers, or broker-held inventory. Date codes will vary, and the tray quantity (standard for 165-FBGA) may not match original reel volumes. Every unit we quote is screened for authenticity and tested to the datasheet limits before shipment. No official replacement part has been announced by Infineon, so any substitution must be validated against the 450 MHz timing, 1.7V–1.9V rail, and FBGA footprint.
165-FBGA — board-level considerations
The 165-ball FBGA (13x15 mm body) uses a standard pitch for this generation of Cypress DDR II+ SRAM. The 1.7V–1.9V supply is tighter than the older 2.5V or 3.3V families — the board regulator must hold that rail within spec under load transients. For rework, the FBGA needs a pre-bake if the moisture barrier has been breached — standard MSL handling applies.