A high efficiency power converter comprises a boost converter for
converting an input voltage to a first voltage on a first output, a buck
converter for converting the input voltage to a second voltage on a
second output, a linear regulator for converting the first voltage to a
third voltage on the second output when the second voltage is lower than
a first threshold, and a voltage detector for detecting the input voltage
for preventing a reverse current flowing from the second output to the
buck converter when the input voltage is lower than a second threshold.