1. LM258DRG3 Substitution Conclusion The LM258DRG3 is pin‑for‑pin compatible (both in 8‑SOIC) and functionally equivalent (dual general‑purpose op‑amp) to the original LT2078IS8TRPBF. However, key parametric differences limit its suitability as a drop‑in replacement: Accuracy: The LM258’s input offset voltage (3 mV) is significantly higher than the LT2078’s (70 µV), which could introduce substantial error in high‑precision amplification or DC signal processing. Power Consumption: The LM258’s quiescent current (500 µA per channel) is roughly ten times that of the LT2078 (47 µA per channel), making it unsuitable for battery‑powered or low‑power systems. Dynamic Performance: The LM258 offers a higher gain‑bandwidth product (700 kHz) and slew rate (0.3 V/µs), making it better suited for mid‑frequency signal processing. In contrast, the LT2078’s extremely low input bias current (6 nA) is more appropriate for high‑impedance sensor interfaces. Supply Compatibility: The LT2078 supports a wider supply range (2.2 V to 36 V), particularly advantageous in low‑voltage or single‑supply designs, whereas the LM258 requires a minimum supply of 3 V. If the application demands tight accuracy, low power, or low‑voltage operation—such as in portable measurement equipment or high‑impedance signal conditioning—substitution is not recommended. The LM258 may be considered only in mid‑frequency, non‑precision, and stable‑supply general‑purpose amplification scenarios, provided system error and power consumption are re‑evaluated.