The breakdown voltage rating of the diode is preferred to be 25% higher than the maximum input voltage. In the target application, the current rating for the diode must be equal to the maximum output current for best reliability in most applications. In cases where the input voltage is not much greater than the output voltage the average diode current is lower. In this case it is possible to use a diode with a lower average current rating, approximately (1-D) × IOUT, however the peak current rating must be higher than the maximum load current. A 1-A to 2-A rated diode is a good starting point.