The CY7C1049B-15VC: It runs on a 4.5–5.5 V supply and comes in a 36-pin SOJ surface-mount package. This part is designed for commercial-temperature (0–70°C) environments.
For a 5 V system running a 33 MHz bus (30 ns cycle), this gives about one clock cycle of margin for address decode, PCB trace delay, and setup time at the controller — tight but workable. Slower 20 ns or 25 ns parts would eat into that margin, potentially forcing a wait state or a slower clock. If your timing closure spreadsheet shows less than 2 ns slack on the address-to-data path, the 15 ns rating is what keeps the bus running at full speed without adding a wait state.
Obsolete — the sourcing reality for CY7C1049B-15VC
Every lot we source is date-code verified against the manufacturer's last production window to avoid post-EOL re-marked parts.
Package and footprint: SOJ-36
The CY7C1049B-15VC is supplied in a 36-pin SOJ package, body width 0.400 inches (10.16 mm).
This limits the part to indoor, temperature-controlled environments.
Supply rail: 5 V only
If your system uses 3.3 V logic, you would need level translators on the address, data, and control lines, which adds cost and board area. The 5 V requirement also affects power budgeting: at 15 ns access time, the dynamic current is higher than a comparable 3.3 V low-power SRAM. For a battery-powered or thermally constrained design, a 3.3 V part would be a better fit.