For a 5V DSP running at 40 MHz to 66 MHz, this gives enough margin to avoid wait states on back-to-back reads. If your system clock is faster than 66 MHz or you need zero dead cycles on a shared bus, you would typically step to a synchronous SRAM or a pipelined NoBL part — but for the installed base of 5V asynchronous designs, 15 ns is the performance tier that keeps the BOM compatible.
For sustainment programs — medical imaging, avionics test equipment, legacy telecom — this part is now sourced through independent distribution on a last-time-buy or surplus basis.
Package and footprint — what the layout engineer needs
The 44-TSOP II (0.400" body width, 10.16 mm) is a surface-mount package with gull-wing leads on 0.8 mm pitch. The footprint matches JEDEC MO-142 variation, and the same land pattern serves the entire CY7C1041B family. Decoupling: place a 0.1 µF ceramic within 3 mm of each VDD pin, plus a 10 µF bulk tantalum near the package. The supply range is 4.5V to 5.5V, so a 5V ±10% rail is within spec. No thermal pad or exposed paddle — all heat dissipates through the leads and the PCB copper.