1. LM2902EDR2G Substitution Conclusion The LM2902EDR2G is not recommended as a direct substitute for the TL074CDG4. Although both parts are pin-compatible quad op-amps, their core electrical specifications are fundamentally different. The TL074CDG4 utilizes a JFET input stage, featuring an extremely low input bias current of 65 pA. This is three orders of magnitude lower than the 90 nA typical of the LM2902EDR2G's general-purpose BJT input stage. Consequently, the TL074CD is specifically designed for applications highly sensitive to input current, such as high-impedance sensor interfaces and precision integrator circuits. Substituting with the LM2902EDR2G in these scenarios would introduce unacceptable errors. Furthermore, the TL074CDG4 offers superior dynamic performance, with a higher gain-bandwidth product (5.25 MHz) and slew rate (13 V/µs), making it suitable for medium-to-high-speed signal processing. In contrast, the LM2902, as a general-purpose low-speed op-amp, typically falls significantly short in these parameters. It is therefore unsuitable for circuits with higher bandwidth demands, such as audio stages or active filters. Substitution may only be considered in non-critical applications like DC or low-frequency general-purpose amplification and voltage comparison, where input impedance, bandwidth, and slew rate are not critical requirements. Even then, a thorough re-evaluation of circuit accuracy and stability is mandatory.