Obsolete — sourcing reality for this 72Mbit DDR II+ SRAM
The CY7C25682KV18-400BZC: This is a 72Mbit synchronous SRAM with DDR II+ architecture, clocked at 400 MHz and organized as 4M x 18 bits.
What the 400 MHz clock and DDR II+ interface mean for your design
The 400 MHz clock rate on a DDR II+ (Double Data Rate, second-generation plus) SRAM means data is transferred on both edges of the clock, yielding an effective 800 MT/s data rate per pin. With a 4M x 18 organization, the part delivers 18-bit-wide data at that rate — suited for high-bandwidth lookup tables, packet buffers, or cache in networking and test equipment where latency matters more than density. The parallel memory interface requires careful PCB routing — the 165-ball FBGA footprint with 0.80 mm ball pitch demands controlled impedance traces and matched-length routing for the address/control bus.
Sourcing an obsolete SRAM — what to expect
Because the CY7C25682KV18-400BZC is obsolete, new stock is sourced through independent distribution and surplus channels.