We are using the MPC5554 in one of our product. A transorb and a capacitor is connected on the ADC input line through 1K ohms series resistor, we will test each and every production board. This testing is in power off condition. Because of the transorb testing, as per simulation we see a voltage of 16Vdc & 20mA for 60mSec on ADC input line in powered off condition. Please let us know, if the 16Vdc & 20mA for 60mS on ADC input line is safe and will not impact the ADC functionality.