18 Mbit DDR II SRAM at 250 MHz — what it delivers on the bus
The Infineon CY7C1318KV18-250BZC is a 18 Mbit synchronous SRAM with a Double Data Rate II interface, organized as 1M x 18. It clocks at 250 MHz, meaning data transfers on both edges of the clock for an effective 500 MT/s throughput on a 18-bit-wide bus. This class of memory is typically specified for high-bandwidth, low-latency applications such as network packet buffers, telecom line cards, test equipment waveform storage, and high-end FPGA cache where the deterministic access time of SRAM beats DRAM's refresh overhead.
Supply rail tolerance — the 200 mV window
That means the PCB's power rail feeding this SRAM needs a regulator with better than ±5% accuracy — a standard 1.8 V rail at ±3% is fine, but a rail that droops below 1.7 V under load will cause read/write failures. Budget a low-noise LDO or a switching regulator with tight load regulation for this rail.
It belongs in office-environment equipment, lab instruments, and climate-controlled telecom shelters. Not specified for outdoor base stations, automotive under-hood, or industrial floor applications without additional system-level thermal management or qualification.
Supplied in a 165-ball LBGA (13x15 mm body, 1.0 mm ball pitch typical for this class). Surface-mount BGA requires a solder reflow profile per J-STD-020, X-ray inspection for voiding and shorts, and controlled impedance layout for the 250 MHz clock traces.
Infineon lists the CY7C1318KV18-250BZC as Active on its product status.