R1 and R2: From the Section 7.2 section, V_OUT1 can be determined to be equal to V_FB × (R1 + R2) / R2, and because V_FB = 2.5 V, the ratio of R1 to R2 calculates as 3:1. Standard values of 3.01 kΩ (R1) and 1.00 kΩ (R2) are chosen. Other values can be used as long as the 3:1 ratio is maintained. The selected values, however, provide a small amount of output loading (2.5 mA) in the event that the main load is disconnected and allows the circuit to maintain regulation until the main load is reconnected.