1. ADM3485EARZ Substitution Conclusion The feasibility of using the ADM3485EARZ as a direct substitute is low, primarily due to critical electrical parameter incompatibilities with the original part. The key discrepancy lies in the supply voltage: the original SP1485EEN-L/TR is designed for a 5V system (4.75V-5.25V), whereas the ADM3485EARZ only supports a 3.3V system (3V-3.6V). Direct substitution would necessitate a redesign of the power supply circuitry; otherwise, the device will not function. Secondly, its data rate (10 Mbps) is only half that of the original part (20 Mbps), directly limiting communication bandwidth and making it unsuitable for high-speed transmission requirements. Although its receiver hysteresis (50 mV) is higher than the original's 20 mV, offering improved signal stability in noisy environments, this advantage does not offset the fundamental voltage and speed mismatches. Substitution may only be considered in applications where speed is not a constraint and the system power supply can be adjusted to 3.3V.