4Mbit async SRAM, 20 ns — the speed grade that matters for bus timing
The CY7C1041BNL-20VXCT is a 4 Mbit asynchronous SRAM organized 256K words by 16 bits, with a 20 ns access time that sets the read-cycle floor on a 5 V parallel bus. At 20 ns, the memory can deliver data within one clock edge of a 50 MHz controller — but the address-to-output propagation, not the clock rate, is the binding constraint for hold-time margin on the bus. If the rest of the board has migrated to lower voltages, a level translator on the address/data bus is needed to avoid over-stressing the SRAM inputs or under-driving the output buffers.
44-SOJ package — footprint and reflow
Housed in a 44-lead SOJ (Small Outline J-lead) package, 0.400-inch body width, 10.16 mm. The J-lead footprint is standard for wide-body SOJ — the same pad pattern used across the Cypress/Infineon 4 Mbit async SRAM family. Tape & Reel packaging feeds directly into pick-and-place; no tube handling required. The commercial temperature grade (0°C to 70°C) limits this to indoor, non-condensing environments. No industrial or automotive qualification — not suitable for engine bay, outdoor telecom cabinets without climate control, or extended cold storage.
For a BOM that requires this exact speed grade (20 ns) and package (44-SOJ), the only path is spot-market procurement.