1. AD8500AKSZ-R2 Substitution Conclusion Direct substitution is entirely non-viable. The AD8500AKSZ-R2 and the original OPA364 differ by orders of magnitude in their core performance specifications, making them devices intended for fundamentally different application scenarios. The AD8500AKSZ-R2 features extremely low gain-bandwidth product (7 kHz) and slew rate (0.004 V/µs). It is only capable of processing signals at very low frequencies with extremely slow transitions, rendering it completely unsuitable for the typical audio, sensor signal conditioning, or ADC buffer applications—which require a certain level of speed—handled by the OPA364 (7 MHz, 5 V/µs). Furthermore, its output drive capability (5 mA) is significantly weaker than that of the OPA364 (85 mA), preventing it from driving similar loads. While its input bias current and offset voltage are comparable or superior to the OPA364, and its quiescent current (750 nA) is exceptionally low, these advantages are only relevant within its intended domain of ultra-low-power, DC or near-DC signal processing (e.g., portable instrumentation, long-term monitoring sensor front-ends). For the original design, a direct substitution would lead to severe degradation of the circuit's dynamic performance or outright functional failure.