The present invention provide a motion detection circuit for a handheld item detection system, where the motion detection circuit includes an accelerometer outputting at least one signal corresponding to a measured acceleration. A differentiator differentiates the measured acceleration. A motion detection device evaluates a discriminated version of the acceleration and a discriminated version of the acceleration to determine whether the handheld item detection system is in motion. The present invention extends battery life and allows a handheld system to quickly enter an active operational mode without any user intervention other than handling (moving) the system.