1. Substitution Conclusion for XC6501C25A7R-G Substitution is feasible, but the application's sensitivity to key parameters must be evaluated. The primary differences are as follows: The substitute's quiescent current (19 µA) is significantly lower than the original's (50 µA), which is beneficial for standby power consumption in battery-powered devices. However, its dropout voltage (0.38V @ 200mA) is substantially higher than the original's (0.17V @ 100mA). When normalized to the same 100mA load, this disparity becomes even more pronounced. With an input voltage close to the output setpoint, the substitute may enter dropout earlier, potentially causing output instability. Furthermore, its Power Supply Rejection Ratio (PSRR) of 50dB is inferior to the original's 70dB, indicating weaker suppression of input ripple and noise. Therefore, substitution is acceptable if the application has stringent low Iq requirements, sufficient input-to-output voltage headroom, and low sensitivity to supply noise. It is not recommended for systems operating near the critical dropout condition or for designs demanding high power supply purity.