Abstract: A single cell power unit for a motorized surgical power tool includes a single cell power unit enclosure. A high temperature battery cell is mechanically supported within and disposed at about a center of the single cell power unit enclosure. An electrical connector having a plurality of connector pins is configured to couple to a mating electrical connector of a tool part having a motor. A motorized surgical handpiece tool which prevents the motor from operating when the power unit is removed, a method to start a multi-phase brushless sensorless motor of a surgical hand piece tool in a controlled manner, a power unit for a motorized surgical power tool with a battery insulated by a flexible circuit boards, and a safety switch system for a motorized surgical power tool with a lever magnet motor speed control are also described.

Abstract: A single cell power unit for a motorized surgical power tool includes a single cell power unit enclosure. A high temperature battery cell is mechanically supported within and disposed at about a center of the single cell power unit enclosure. An electrical connector having a plurality of connector pins is configured to couple to a mating electrical connector of a tool part having a motor. A motorized surgical handpiece tool which prevents the motor from operating when the power unit is removed, a method to start a multi-phase brushless sensorless motor of a surgical hand piece tool in a controlled manner, a power unit for a motorized surgical power tool with a battery insulated by a flexible circuit boards, and a safety switch system for a motorized surgical power tool with a lever magnet motor speed control are also described.

Abstract: A single cell power unit for a motorized surgical power tool includes a single cell power unit enclosure. A high temperature battery cell is mechanically supported within and disposed at about a center of the single cell power unit enclosure. An electrical connector having a plurality of connector pins is configured to couple to a mating electrical connector of a tool part having a motor. A motorized surgical handpiece tool which prevents the motor from operating when the power unit is removed, a method to start a multi-phase brushless sensorless motor of a surgical hand piece tool in a controlled manner, a power unit for a motorized surgical power tool with a battery insulated by a flexible circuit boards, and a safety switch system for a motorized surgical power tool with a lever magnet motor speed control are also described.

Abstract: A minimally invasive detection circuit for determining whether a current flow is present in an electrical conductor, such as a telephone line, without appreciably loading the conductor. A load is placed in series with the conductor to generate a voltage drop when current flows therethrough. The voltage drop is detected by powered components that provide a signal, across an electrical isolation barrier, to an electrically isolated output. The powered components are powered by a voltage source that is on the isolated or remote side of the isolation barrier and whose voltage output is provided to the powered components across the isolation barrier so as to maintain electrical isolation between the powered components and the output and thereby avoid unnecessary loading of the conductor.