In accordance with one embodiment of the present invention, a circuit provides power stability functions for a
microcontroller, during startup and normal operations performing
power on reset functions and an array of power stability functions. The
power on reset functions hold the
microcontroller in a safe reset condition, reinforce the POR hold, and force its switch mode pump to drive up
voltage provided to its common supply source. The power stability functions constitute a
power on reset function, a power supply health, e.g., power state
condition monitoring function, a
control function for dynamically controlling the common supply source, and auxiliary functions, which may be protective of a
flash memory. The power on reset function operates at a fixed and / or programmably changeable
voltage levels. In one embodiment, the POR circuit is interconnected with a processor through a
bus, enabling programmatic processor control of
microcontroller power through interaction with the POR circuitry.