Synchronous FIFO for real-time data buffering — now obsolete
The Cypress CY7C4241V-15JC is a synchronous FIFO memory with a 4K x 9 (36K) depth, clocked at 66.7 MHz and delivering an 11 ns access time. Typical applications include telecom line buffers, video frame stores, and any real-time data pipeline needing a fixed-depth queue with no FWFT support. The part supports depth and width expansion, and its programmable flags offload the host from tracking fill level.
At 66.7 MHz the FIFO can sustain a read or write every 15 ns cycle, with the 11 ns access time meaning the first data word appears on the bus within 11 ns of the read-enable edge. This gives roughly 4 ns of setup margin to a 66 MHz DSP or FPGA interface, enough for most synchronous backplanes without adding wait states. The 20 mA max supply current is modest for a 66 MHz synchronous part, keeping the thermal budget in the PLCC package manageable.
The CY7C4241V-15JC is marked obsolete by Cypress (now Infineon). For BOM lines still carrying this part, supply runs through independent distribution — new-old-stock or surplus lots, date-code and condition verified. There is no last-time-buy window open; buyers should qualify a drop-in replacement or secure remaining inventory while it is still findable.
Package and footprint — 32-PLCC (J-Lead)
The 32-PLCC (J-Lead) package measures 11.43 x 13.97 mm. It is a surface-mount, J-bend lead form suited for reflow or wave solder. The J-Lead gives a smaller footprint than an SOJ but requires a matching PLCC footprint — verify the land pattern against the supplier device package drawing before committing the board.