1. LM258AST Substitution Conclusion From the perspective of key performance parameters, direct substitution of MC33078DGKR with LM258AST carries significant risks and is generally not recommended. The primary differences are as follows: The LM258AST has a gain-bandwidth product (1.1 MHz) and slew rate (0.6 V/µs) far lower than those of the original part (16 MHz, 7 V/µs). This will result in significantly slower response when processing high-frequency or fast-changing signals, potentially leading to waveform distortion or insufficient dynamic performance. Moreover, its input offset voltage (1 mV) is an order of magnitude higher than that of the original part (150 µV), directly degrading DC accuracy and likely failing to meet error requirements in applications demanding high-precision amplification. Although the LM258AST offers advantages such as lower power consumption, a wider single-supply operating voltage range (3–30V), and automotive-grade qualification, these benefits cannot compensate for its critical shortcomings in bandwidth, speed, and accuracy. Therefore, it is only suitable as a substitute in low-frequency, non-precision applications with minimal demands for dynamic performance and accuracy.