Asynchronous FIFO — 9K buffer, 20 ns access, 50 MHz ceiling
The CY7C425-20VXCT is a 9K (1K x 9) asynchronous FIFO with 20 ns access time and 50 MHz data rate. It operates from 4.5 V to 5.5 V supply and is rated 0°C to 70°C.
The 20 ns access time means the FIFO can present valid data on the output bus within 20 ns of the read enable going active. For a system running a 50 MHz read clock (20 ns period), this timing leaves essentially no margin for board trace delay or logic propagation — the host controller must latch the data on the same clock edge that drives the read enable. Designs with slower controllers or relaxed timing can run comfortably below the 50 MHz ceiling, but the 20 ns access is the hard floor for cycle time.
Commercial temperature only — indoor, controlled environments
Not suitable for automotive under-hood, outdoor telecom cabinets, or factory floor applications without thermal management.
The CY7C425-20VXCT is formally obsolete per Cypress's product lifecycle status. No official replacement order code is listed in the available documentation.
No FWFT — standard asynchronous handshake only
This FIFO does not support First-Word Fall-Through (FWFT) operation. Data is read using the standard asynchronous handshake: the empty flag goes low when data is available, the host asserts read enable, and data appears on the bus after the access time. No automatic data pre-fetch on the output — the controller must manage the read cycle explicitly.
28-SOJ surface mount — compact footprint for dense boards
Packaged in a 28-lead SOJ (Small Outline J-lead) body, 0.300-inch wide, 7.62 mm pitch. Surface mount only — no through-hole variant in this order code.