A circuit for generating a voltage waveform at an output node includes a first voltage rail configured to be held at a first voltage, the first voltage rail being connected to the output node via a first voltage rail switch, a second voltage rail configured to be held at a second voltage that is different from the first voltage, the second voltage rail being connected to the output node via a second voltage rail switch, at least one anchor node connected to the output node via an inductor and an anchor node switch, and a control unit configured to switch the circuit between: a first voltage outputting state in which the first voltage rail switch is closed and the second voltage rail switch is open, and a second voltage outputting producing state in which the second voltage rail switch is closed and the first voltage rail switch is open.