Patent ID: 6611921
Filing Date: 2003-08-26
Classification: G06F,Y02D

Abstract:
A user operated data input device comprising:first and second data input signal generating means for generating respective first and second data input signals; a power supply for selectively supplying electrical power to said first and second input signal generating means; a sensing system for sensing the presence of an operation instrumentality in contact with or close proximity to said input device and generating a signal indicative of an ON state wherein said operation instrumentality is in contact with or close proximity to said input device, and an OFF state wherein said operation instrumentality is not in contact with or close proximity to said input device; a power management system for controlling the supply of power to said first and second input signal generating means, said power management system providing switching between at least three power states, wherein: in a first of said power states each of said first and second input signal generating means is powered-up to a normal operation level and sampled for input activity; in a second of said power states each of said first and second input signal generating means are cycled between a powered-up state wherein sampling for input activity is carried out, and a powered down state; in a third of said power states said first signal generating means remains powered down while said second signal generating means is cycled between a powered-up state wherein sampling for input activity is carried out, and a powered down state; a transition from said first power state to said third power state occurs upon a transition of said sensing system from said ON state to said OFF state; a transition from said third power state to one of said first and second power states occurs upon a transition of said sensing system from said OFF state to said ON state; and a transition from said second power state to said first power state occurs upon a detection of input activity during said sampling of said first and second input signal generating means.