1. LTC2857IMS8-1TRPBF Substitution Conclusion Direct substitution of the LTC2857IMS8-1TRPBF for the ISL83078EIUZA-T is generally not feasible due to two critical technical differences. First, the supply voltage ranges differ: the LTC2857 requires 4.5V to 5.5V, whereas the original part operates from 3V to 3.6V. Direct replacement could result in power supply incompatibility or device damage. Second, the duplex modes are mismatched: the LTC2857 supports full-duplex operation, while the original device is half-duplex. This difference affects communication protocol and circuit design, as full-duplex requires separate transmit and receive channels, potentially necessitating hardware connection changes and software reconfiguration. Although both devices support RS422/RS485 standards, offer the same data rate (20Mbps) and package (8-MSOP), and the LTC2857 provides higher receiver hysteresis (25mV) for slightly improved noise immunity, the voltage and duplex mismatches require reevaluation of the power architecture and communication design. Therefore, this is not a drop-in compatible solution.