The CY7C425-10AXCT: The 10 ns access time sets the window for the read-enable-to-data-valid timing; at 50 MHz the write cycle is 20 ns, so the 10 ns access gives roughly half a cycle for the read side to settle before the next edge. The 9-bit width (8 data plus one parity bit) suits designs that need a parity lane without a second device. The 32-TQFP (7x7 mm) package is a surface-mount footprint common for mid-density FIFOs.
Cypress lists the CY7C425-10AXCT as Obsolete. No last-time-buy window or successor part is recorded in the official lifecycle data. Stock that surfaces now comes from distributor overstock or end-of-life buy lots; date-code verification and basic parametric screening (access time, supply current) are recommended before committing to a production run.
Retransmit capability and expansion
The device supports retransmit — a feature that lets the read pointer reset to the beginning of the stored data without a full FIFO reset, useful in packet retry or error-recovery flows. Expansion is depth- and width-expandable, meaning multiple CY7C425-10AXCTs can be cascaded for larger buffers (wider data words or deeper queues) using external logic. No FWFT (First-Word Fall-Through) or programmable flags are supported; flag logic is fixed (empty, full, half-full, and retransmit).
This limits the CY7C425-10AXCT to indoor, temperature-controlled equipment — telecom line cards, test equipment, industrial controllers in conditioned cabinets, and similar environments where the ambient stays within the commercial window. Not suitable for outdoor, under-hood, or extended-temperature industrial zones without active thermal management.