1. 71V65703S80BQGI Substitution Conclusion From the perspectives of core electrical parameters, package, and functionality, the 71V65703S80BQGI is a highly viable direct replacement. Both devices are 3.3V, 256Kx36 organization, synchronous SRAMs in a 165-TBGA package, sharing the same rated operating frequency. The key differences are as follows: First, its access time (tAA) is 8ns, which is slightly slower than the original part's 7.5ns. This results in a marginally larger data output delay at the same 117MHz clock frequency, requiring verification of adequate system timing margin. Second, it is designated with "ZBT" (Zero Bus Turnaround) technology. This is an enhanced synchronous SRAM architecture designed to eliminate idle cycles between read and write operations. Compared to the original part's standard synchronous SDR architecture, ZBT theoretically offers higher data throughput efficiency during back-to-back read/write switching. However, it is crucial to confirm that the host controller can correctly adapt to the ZBT protocol timing. Provided the system timing meets the 8ns access time requirement and the controller is compatible with (or does not conflict with) ZBT, this part can successfully serve as a replacement.