72 Mbit DDR-II SRAM at 200 MHz — bus timing and buffer depth
The Infineon CY7C1520AV18-200BZI is a 72 Mbit synchronous DDR-II SRAM organized as 2M x 36 bits, clocked at 200 MHz over a parallel interface. The 1.7 V to 1.9 V core supply and -40 to 85 °C temperature range suit industrial applications.
At 200 MHz the DDR-II interface transfers data on both clock edges. The synchronous double-data-rate architecture eliminates dead cycles on back-to-back reads and writes.
Package and footprint — 165-FBGA (15x17 mm)
The 165-ball FBGA measures 15 mm by 17 mm, a standard high-density SRAM footprint. Board layout must route the 36 data lines plus address and control signals with matched trace lengths to maintain setup/hold margins at 200 MHz. The fine-pitch BGA requires micro-via or blind-via stack-ups on anything above two layers; a four-layer PCB with a dedicated VDD plane and ground plane is the typical starting point.
