1. ADA4622-1BRZ-R7 Substitution Conclusion The ADA4622-1BRZ-R7 can serve as a direct drop-in replacement for the OPA197IDR in terms of package and basic functionality, but critical performance differences must be carefully evaluated. The ADA4622-1BRZ-R7 features a J‑FET input stage, offering an input bias current of 2 pA, which is significantly lower than the 5 pA typical of the BJT‑input OPA197. This makes it advantageous for applications with high‑impedance signal sources. However, its input offset voltage of 400 µV is considerably higher than the OPA197’s 25 µV, which may degrade DC accuracy and introduce errors in precision measurement circuits. Additionally, the ADA4622-1BRZ-R7 has a slightly narrower supply range (5 V to 30 V) compared to the OPA197 (4.5 V to 36 V), potentially limiting its use in wide‑supply or low‑voltage applications. On the other hand, its lower quiescent current (715 µA) contributes to better power efficiency. In summary, substitution is feasible if the application is not sensitive to offset voltage and requires high input impedance. If high DC precision or a wider supply range is critical, a redesign or device screening is recommended.