2. IS64LF25636A-7.5B3LA3-TR Substitution Conclusion Requires careful evaluation, as it is a potential substitute with similar parameters but a different architecture. Two primary differences exist: first, its access time is shorter (7.5 ns), offering better performance; second, and more critically, its technical description lacks the "ZBT" designation, indicating it is likely a standard synchronous SDR SRAM that does not support the Zero Bus Turnaround (ZBT) protocol. While capacity, voltage, and package are identical, the absence of ZBT means its read/write timing cycles may not be fully compatible with the original part. If the host controller is designed for ZBT timing, direct substitution could lead to system instability or suboptimal performance. Rigorous timing verification is mandatory.