A method and apparatus for implementing a CMOS buffer for driving a reference voltage that consumes very low current in normal operating conditions but drive high current when output voltage is off, tracking the required reference voltage. The circuit is operating in a “deadzone” most of the time, where pull-up and pull-down current paths are blocked, and ultra-low power comparators, with build-in offset, are monitoring the output voltage continuously, and driving compensation current, when needed. The circuit can be manufactured with a standard CMOS processing technology.