1. XC6501A2717R-G Substitution Conclusion The substitution is feasible under the premise of basic functionality and package compatibility, but involves clear performance degradation and requires careful evaluation based on the application. The key differences are as follows: First, the dropout voltage increases significantly, from 0.17V@100mA for the original part to 0.38V@200mA. Under full load or during input voltage sags, the substitute requires a higher minimum input voltage (Vin_min ≈ Vout + 0.38V) to maintain a stable output, reducing the operating margin in low-input-voltage applications such as battery-powered systems. Second, the quiescent current increases from 8µA to 20µA, a rise of approximately 1.5x. This directly increases system power consumption in always-on standby circuits, adversely affecting battery life. Third, the power supply rejection ratio degrades from 70dB to 50dB (@1kHz). The substitute's ability to reject noise introduced from the power supply, particularly in the mid-frequency range, is inferior. When used in circuits with significant supply ripple or in noise-sensitive analog/RF applications, this may lead to degraded output power quality.