Patent ID: 6549056
Filing Date: 2003-04-15
Classification: H03F

Abstract:
A galvanically isolating circuit for converting an input voltage to an output variable, the output variable being either and output voltage or an output current, the circuit comprising:a first input terminal and a second input terminal for receiving the input voltage; a first output terminal and a second output terminal for producing the output variable; and a serial capacitance section for providing galvanic isolation from the input terminals to the output terminals, that galvanically isolating circuit further comprising: a first polarity switching means arranged to operationally connect the input terminals to the serial capacitance section by periodically reversing the polarity of the input terminals; a second polarity switching means arranged to operationally connect the serial capacitance section to the output terminals by periodically reversing the polarity of the output terminals, in synchronism with the first polarity switching means, the first polarity switching means comprising: a control input for receiving a control signal comprising a first half cycle and a second half cycle; a first transistor for connecting the first input terminal to a first capacitor of the serial capacitance section during said second half cycle; and a second transistor for connecting the second input terminal to the first capacitor of the serial capacitance section during said second half cycle, wherein the control input is operationally connected to control contacts of the transistors through a galvanically isolating connection.