1. Reverse Leakage Current (Ir @ Vr): PG5391 is rated at 1µA, while the 1N5391GP-TP is rated at 5µA. The MCC device exhibits a slightly higher off-state leakage at maximum rated junction temperature and voltage. However, for typical 50V, 1.5A general rectifier circuits, both values fall within the standard range. This discrepancy has no material impact on circuit functionality, such as efficiency or thermal performance. 2. Junction Capacitance (Cj @ Vr, F): PG5391 is specified at 25pF, compared to 15pF for the 1N5391GP-TP. The lower junction capacitance of the MCC device may offer marginally better impedance characteristics at high frequencies, potentially resulting in less switching harmonic noise. Nevertheless, for the line-frequency or low-frequency rectification applications both parts target, this parameter difference holds no practical significance. 3. Manufacturer & Price: The different manufacturers (Panjit vs. MCC) lead to a significant price difference ($0.24 vs. $0.06). This reflects factors like brand premium, supply chain costs, or minor process variations, which are not evident in the core electrical specifications. For cost-sensitive designs, the MCC part offers a clear advantage. Overall Assessment: The key parameters (Vr, Io, Vf, Speed, Package) for both devices are identical. The noted differences fall within the normal parameter distribution range for standard rectifier diodes of this class and do not affect basic rectification function or reliability. When substituting, it is recommended to verify compatibility under specific application conditions (e.g., extreme temperatures, peak current) in the final product and to consider long-term supply stability.