Asynchronous FIFO — 10 ns access, 9-bit wide, 5 V only
The Cypress CY7C460A-10JC is a 72K (8K x 9) asynchronous FIFO memory from the CY7C series, designed for buffering data between asynchronous clock domains in 5 V logic systems. Its 10 ns access time and 50 MHz data rate support back-to-back read/write cycles without dead cycles, critical for maintaining throughput in real-time data acquisition or telecom line-card applications. The 9-bit width accommodates an eighth data bit plus a ninth bit for parity, tag, or control signaling — a common requirement in datacom framing and storage controllers. It supports depth and width expansion for scaling buffer capacity, and includes retransmit capability for re-reading data without a full reset — useful in protocol retry sequences.
Cypress (now part of Infineon) no longer produces this FIFO in volume, and no direct replacement with the same pinout and function is listed in the current portfolio. For a BOM line that must be filled, the procurement path is spot-market or surplus inventory. The 32-PLCC footprint is not shared by newer FIFO families, so a board redesign would be required to migrate to an active alternative. If this is a repair or legacy-production run, securing a last-time-buy quantity through a broker is the standard approach.
5 V supply and commercial temperature — fit check
Maximum supply current of 60 mA is modest for a 72K FIFO at 50 MHz; the 10 ns access time gives the system designer a 100 MHz equivalent read/write cycle window when accounting for setup and hold margins on a 5 V bus.