A system and method to provide voltage to a device from the operating mode
of an integrated circuit is disclosed. In a particular embodiment, the
disclosed system includes an integrated circuit having an input/output
pin and a DC-DC converter circuit that is coupled to the input/output pin
and including a transistor element. The DC-DC converter circuit has a
first mode of operation and a second mode of operation. In the first mode
of operation, the DC-DC converter circuit performs voltage conversion and
in the second mode of operation, the transistor element of the DC-DC
converter circuit is used to selectively apply a voltage supply to an
external module coupled to the input/output pin.