72Mbit DDR II+ SRAM at 400 MHz — what the specs mean for a BOM line
The CY7C2568KV18-400BZXC is a 72Mbit synchronous SRAM from Infineon, organized as 4M x 18 and clocked at 400 MHz. The DDR II+ interface doubles data rate on each clock edge, delivering a peak read/write bandwidth of 7.2 Gbps across the 18-bit parallel bus — the 400 MHz clock is the limiting factor for latency-critical look-up tables and packet buffers in high-end networking or test equipment. Operating from a 1.7V to 1.9V core supply, this part sits in the low-voltage SRAM family that reduces I/O power without sacrificing throughput. The commercial temperature range (0°C to 70°C) suits controlled-environment racks and lab instrumentation.
Obsolete — sourcing reality and the last-time-buy window
Infineon lists the CY7C2568KV18-400BZXC as Obsolete. No official successor part number is recorded, meaning a direct pin-compatible drop-in from the same manufacturer is not available. For existing designs already qualified to this SRAM, the only path is the surplus and broker channel. We source this part through independent distribution — each lot is verified for date-code authenticity and traceability.
Package and board-fit — 165-FBGA footprint
The fine-pitch BGA demands a multi-layer PCB with controlled impedance for the parallel data bus at 400 MHz — signal integrity on the DQ and address lines is critical at this speed. Supplied in tray packaging, it is suitable for pick-and-place assembly in medium-to-high volume production. The 1.7V-1.9V supply rail must be clean; a dedicated LDO or switching regulator with low ripple is recommended to stay within the SRAM's voltage tolerance.