1. XC6501C25A7R-G Substitution Conclusion Based on a parameter comparison, the XC6501C25A7R-G is compatible in basic functionality (input/output voltage, current, enable control) and package footprint. However, it is not recommended as a direct substitute. The key differences are as follows: its dropout voltage is significantly higher (0.38V @200mA vs. 0.17V @100mA), making it more prone to entering dropout prematurely in low-input-voltage or battery-powered applications, which can lead to unstable output; its quiescent current is higher (19µA vs. 8µA), which is detrimental for portable devices sensitive to battery life; and its power supply rejection ratio (PSRR) is notably lower (50dB vs. 70dB @1kHz), resulting in poorer suppression of input ripple and noise that may affect the performance of downstream sensitive circuits. Substitution may only be considered in applications where dropout, power consumption, and noise rejection are not critical requirements. Otherwise, it is not advised.