Patent ID: 7629771
Filing Date: 2009-12-08
Classification: H02H

Abstract:
1. A protection device for non-common ground buses, the non-common ground buses including a first bus and a second bus, the protection device comprising: a controller coupled in parallel to a battery, the controller generating a first control signal and a second control signal; a level shifter coupled to the battery and the controller, the level shifter receiving the first control signal and generating a third control signal; a first group of switches coupled to the controller via the first bus and to an external element via the second bus, the first group of switches being controlled by the second control signal from the controller and the third control signal from the level shifter; and a second group of switches coupled between a ground terminal of the battery and a ground terminal of the external element, the second group of switches being controlled by the second control signal from the controller and the third control signal from the level shifter, wherein at least part of the first group of switches are turned off to isolate the first bus from the second bus when an abnormal situation occurs.