Patent ID: 7834725

Claim:
A circuit comprising: a magnetically sensitive latching device operatively configured and arranged to change from a first output state to a second output state as a function of a magnetic field applied in a first direction, to maintain said second output state when said magnetic field is either no longer applied in said first direction or applied again in said first direction, and to change from said second output state to said first output state as a function of a magnetic field applied in a second direction different from said first direction; a power switching device coupled between a power source and a load; said power switching device coupled to said magnetically sensitive latching device; said magnetically sensitive latching device and said power switching device operatively configured and arranged such that said power switching device connects said power source and said load when said magnetically sensitive latching device is in said second state and disconnects said power source and said load when said magnetically sensitive latching device is in said first state; said magnetically sensitive latching device coupled to said power source; a magnetic switching device coupled between said magnetically sensitive latching device and said power source; said magnetic switching device having an open disconnected default state and operatively configured and arranged to change from said open default state to a closed connected state when said magnetic field is applied in said first direction and to return to said open default state when said magnetic field is removed; said power source, said magnetically sensitive latching device and said magnetic switching device arranged such that said magnetic field applied in said first direction causes said magnetic switching device to change from said open default state to said closed connected state, thereby powering said magnetically sensitive latching device, and said magnetically sensitive latching device to change from said first state to said second state, thereby signaling said power switching device to connect said power source and said load.