250 MHz QDR II — throughput and bus fit
The CY7C1314KV18-250BZI is a 18 Mbit QDR II synchronous SRAM organized as 512K x 36, clocked at 250 MHz. The QDR II interface delivers two data words per clock cycle on separate read and write ports, so the 250 MHz clock yields an effective 500 MHz data rate on each port — the bandwidth ceiling is set by the bus turnaround, not the core access time. The 36-bit word width maps directly to 36-bit wide lookup tables or tag RAMs in networking equipment — a single device covers a full 36-bit data path without byte-level muxing. The 1.7 V to 1.9 V supply rail is tighter than a standard 1.8 V ±5 %; the PCB regulator must hold within 100 mV across load transients to stay inside the operating window.
The 165-FBGA (13x15 mm) footprint uses a 1.0 mm ball pitch — standard PCB fab and X-ray inspection, but the BGA reflow profile must follow the JEDEC MSL rating on the reel label to avoid popcorning. The 165-LBGA package is the same body size as the FBGA variant; the 'L' prefix indicates a low-profile ball grid array with a seated height under 1.4 mm. Surface-mount assembly with no underfill is typical for this ball pitch in telecom line-card volumes.