A power manager for managing power delivered to a battery operated
peripheral device is disclosed. The power manager includes an input
current limiter arranged to suppress a power surge associated with an
insertion event by a power cable arranged to provide an external voltage.
A voltage converter unit coupled to the input current limiter converts
the received external voltage to a supply voltage that is transmitted by
way of a main bus to a voltage sensor unit coupled thereto. During the
insertion event, a comparator unit coupled to the voltage sensor, sends a
first switching signal to a switchover circuit that responds by
connecting the peripheral device and an uncharged battery to the main bus
such that the supply voltage is provided thereto. When the battery is
substantially fully charged, the switchover circuit responds by
electrically disconnecting the battery so as to not overcharge the
battery.