A method and system are disclosed for improving the efficiency of a
battery supplied power supply system. More particularly, a method and
system is provided for improving the voltage regulation efficiency for a
system in which the input voltage that is to be regulated may vary
widely. In the techniques disclosed, the voltage supply that is utilized
for the drive control circuitry of the voltage regulators is varied in
relation to variations in the input voltage. Thus in one embodiment, the
voltage supply that is utilized for the circuitry that drives a control
terminal of the output transistor of the regulation circuitry may be
varied in relation to variations in the input voltage. For example, an
inverse relationship may be established between the input voltage level
and the voltage level that is used for the gate drive circuitry that
controls the gates of regulator output transistors.