Patent ID: 7672806

Claim:
A portable device controlled by user-imparted motion, comprising: a handheld portable device; a detection device comprising: an acceleration sensor generating a first acceleration signal relating to a first axis of detection in response to user-imparted motion of the handheld portable device, and a displacement detection circuit connected to said acceleration sensor and comprising a first comparator stage for comparing said first acceleration signal with a first acceleration threshold and generating a first displacement detection signal indicative of a displacement of the device along the first axis of detection of the acceleration sensor relative to a reference position, said displacement detection circuit further comprises first filtering means arranged between said acceleration sensor and said first comparator stage and configured to reduce a DC component of said first acceleration signal that is due to an acceleration of gravity and reset the reference position of the device, the displacement detection circuit further comprising a hysteresis memory element having a first input and a second input; said first comparator stage having an output connected to said first input, and a second comparator stage having an output connected to said second input and adapted to compare said first acceleration signal with a second acceleration threshold lower than said first acceleration threshold; and a microprocessor coupled to the displacement detection circuit to generate control signals to the handheld portable device.