What this 18Mbit DDR II+ SRAM does in the system
The Infineon CY7C1168KV18-550BZXC is a 18Mbit synchronous SRAM using DDR II+ architecture, organized as 1M x 18 bits and clocked at 550 MHz. It sits in the high-speed data path — think network switch buffers, test equipment capture memory, or any design that needs back-to-back read/write throughput without dead cycles. The DDR II+ interface doubles the data rate on each clock edge, so the controller sees 1.1 G transfers per second on the data bus. Supply runs from 1.7V to 1.9V, which means a clean 1.8V rail is expected — no mixing with 3.3V or 2.5V I/O domains without level translation.
At 550 MHz, this part is built for the fast lane. The DDR II+ architecture means data transfers on both rising and falling clock edges, so the effective data rate is 1.1 G transfers per second per pin. For a 36-bit or 72-bit memory bus, that adds up fast. The trade-off: timing closure on the PCB gets tighter — trace length matching and signal integrity matter more than with slower synchronous SRAM. If your FPGA or ASIC memory controller doesn't support DDR II+ at this speed, the part won't run at its rated clock. Check the controller's I/O timing budget before committing the BOM line.
Package and board integration — 165-FBGA
The 165-FBGA (13x15 mm) is a fine-pitch BGA. No lab, no bench — you need a reflow oven and X-ray inspection to verify solder joints. The 1.7V to 1.9V core supply means dedicated power plane or a local LDO feeding the VDD pins. Decoupling should follow the layout guidelines in the datasheet; at 550 MHz, the transient current draw is fast enough that a few nH of via inductance can cause supply droop.
For production planning, that means it's still a supported, manufacturable part — no last-time-buy crunch to navigate.