The output current of a fixed-frequency DC to DC converter is sensed, creating a voltage representative of the load current. This voltage is then compared to one or more threshold voltages using a plurality of comparators, creating a plurality of logic signals indicative of which of a plurality of ranges the output current falls within. These logic signals are coupled to a multiplexer which decodes the logical inputs to one-of-n and selects one gate drive voltage from a plurality of such voltages, each optimized for its corresponding current range. The selected gate drive voltage is then used as the gate drive in a known art DC to DC converter, thereby increasing efficiency over a wide range of output current.