Abstract: An apparatus for enabling an IC pin to function in a dual mode, which apparatus includes a first switch for coupling the IC pin to an input terminal when the IC pin operates in an input mode, and a charging circuit for sourcing current to the IC pin during a charging cycle of a timer mode. The inventive apparatus further includes a discharging circuit for sinking current from the IC pin during a discharging cycle of the timer mode. In one embodiment, the inventive apparatus further includes a comparator for generating an activation signal, the activation signal being activated when a potential at the IC pin equals or exceeds a predefined voltage in the timer mode. In another embodiment, the comparator is disabled during the input mode.

Abstract: A charge pump circuit operates from a voltage provided on an input rail at a first potential relative to a reference potential rail and that provides second and third potentials relative to the reference potential rail on first and second output rails, respectively. The charge pump circuit includes first, second and third charge reservoir capacitors, an oscillator and control logic circuit for providing timing control signals, and a switch network responsive to the timing control signals for coupling the first, second and third capacitors in a plurality of configurations.

Abstract: A charge pump circuit operates from a voltage provided on an input rail at a first potential relative to a reference potential rail and that provides second and third potentials relative to the reference potential rail on first and second output rails, respectively. The charge pump circuit includes first, second and third charge reservoir capacitors, an oscillator and control logic circuit for providing timing control signals, and a switch network responsive to the timing control signals for coupling the first, second and third capacitors in a plurality of configurations. The switch network also provides for the decoupling of the capacitors from between the input rail and the reference potential rail between transitions of these configurations.