The Infineon CY7C1515AV18-250BZC is a 72 Mbit Quad Data Rate II synchronous SRAM organized as 2M x 36 bits, clocked at 250 MHz. QDR II architecture delivers separate read and write data ports, eliminating bus-turnaround dead cycles that standard synchronous SRAM incurs on mixed read/write traffic.
250 MHz clock — timing margin and bus design
The 250 MHz clock rate defines the data rate at 500 MT/s per port (double-data-rate on both read and write clocks). At this speed, board-level signal integrity becomes the limiting factor: trace-length matching within ±50 ps, controlled impedance, and minimal via stubs on the FBGA fan-out are non-negotiable. The parallel interface uses separate address and control buses for read and write, so the pin count is high (165 balls) but the protocol avoids the arbitration overhead of a shared bus.
The core supply range of 1.7V to 1.9V centers on a nominal 1.8V rail. The ±0.1V tolerance is tighter than a typical 1.8V ±5% regulator output, so the power rail needs a low-noise LDO or a switching regulator with <10 mV ripple. Each supply ball should see a 100 nF ceramic within 2 mm of the ball, plus a 10 µF bulk cap per quadrant of the FBGA. The 165-ball FBGA (15x17 mm) has a 1.0 mm ball pitch — standard PCB fab can route two traces between balls, but a four-layer stackup with a dedicated power plane is recommended to keep IR drop under 30 mV across the array.
Infineon (formerly Cypress) no longer manufactures this specific speed/density/temperature variant. If the board is still in design, consider migrating to a current-generation QDR II+ or QDR IV device before the layout is locked.