Patent ID: 7508096

Claim:
A circuit for servicing a load connectable with a power supply, the circuit comprising: a plurality of three-terminal switches which define a series conduction path connectable between the power supply and the load, the series conduction path comprising a source terminal and a drain terminal of each of the plurality of three-terminal switches, and each source terminal of the plurality of three-terminal switches is connected to a drain terminal of an adjacent three-terminal switch, respectively; one control supply in power connection between a gate terminal of each of the plurality of three-terminal switches and a source terminal of one of the plurality of three-terminal switches, the control supply producing a control voltage; and a plurality of isolator circuits corresponding to the plurality of three-terminal switches, and each disposed in power connection between the one control supply and a source terminal and a gate terminal of each of the three-terminal switches of the plurality of three-terminal switches, and comprising a transformer which transforms the control voltage received from the one control supply at the respective three-terminal switch into a specified voltage to close the respective three-terminal switch, and each of the plurality of three-terminal switches is responsive to the control voltage at its respective gate terminal, thereby closing a connection between the respective source terminal and respective drain terminal of each of the plurality of three-terminal switches based on the specified voltage.