Synchronous FIFO for buffered data paths
The Infineon (Cypress) CY7C4231V-25AXCT is a synchronous FIFO memory from the CY7C series, organized as 2K x 9 bits (18K total).
At 40 MHz, the cycle period is 25 ns, leaving 10 ns of margin beyond the access time for clock skew, PCB trace delay, and setup/hold at the receiving logic. This margin is adequate for backplane or mid-plane designs with moderate trace lengths, but a timing analysis should confirm hold times at the load side, especially if the FIFO is clocked from a separate PLL domain.
Infineon (formerly Cypress) has discontinued this specific variant. For BOM lines requiring this exact part, procurement must rely on independent distribution channels, where inventory is sourced from surplus, overstock, or last-time-buy stockpiles.
Package and footprint — 32-TQFP (7x7 mm)
This is a surface-mount, fine-pitch quad flat pack requiring reflow soldering. The Tape & Reel (TR) packaging indicates it was originally intended for automated pick-and-place assembly.
Programmable flags and expansion support
The FIFO supports programmable flags for almost-full and almost-empty thresholds, which allows the system to manage flow control without polling the fill level. Expansion in both depth and width is supported, enabling cascading multiple devices for larger buffer sizes or wider data words. Note that retransmit capability and FWFT (First-Word Fall-Through) support are not available on this part, so designs relying on those features will need a different FIFO family.