The present invention comprises a microcontroller unit including a
processor for generating a power down signal. Control logic generates a
hold signal responsive to the power down signal. A voltage regulator
provides a regulated voltage responsive to an input voltage and powers
down responsive to the power down signal. At least one digital device
powered by the regulated voltage enters a powered down mode responsive to
the voltage regulator entering the powered down state. The at least one
digital device provides at least one digital output signal that is
provided to an input/output cell. The input/output cell also is connected
to receive a hold signal. The input/output cell maintains a last state of
the digital output signal responsive to the hold signal when the at least
one digital device enters the powered down state.