1. LM2904D Substitution Conclusion Direct substitution is not recommended. The LM2904D is a standard bipolar-input operational amplifier. Its input bias current (20 nA) is nearly three orders of magnitude higher than that of the original J-FET type TL062 (30 pA). When used in applications such as high-impedance signal sources, integrator circuits, or precision current sensing, this will result in significantly greater input error and offset voltage. Furthermore, its slew rate (0.3 V/µs) is only about one-tenth that of the TL062 (3.5 V/µs). This severely limits signal processing speed and large-signal bandwidth, leading to degraded square-wave response and distortion of high-speed waveforms. Although the two are pin-compatible and have partially overlapping supply voltage ranges, their fundamental input architectures and dynamic performance differ substantially. Substitution may only be considered for general-purpose amplification applications with minimal requirements for input current and signal speed, and a full circuit performance re-evaluation would be mandatory.