A level shifter circuit is provided that uses a boosting circuit. The boosting circuit is configured to improve the operation of the level shifter circuit when the high voltages of voltage domains across the level shifter circuit are widely separated. A circuit apparatus includes a core level shifter circuit that changes a first voltage of an input signal to a second voltage of an output signal. The circuit apparatus further includes a first boosting circuit that is coupled to the core level shifter circuit and generates a first transient voltage applied to the core level shifter circuit when the input signal transitions from a low value to a high value. The circuit apparatus also includes a second boosting circuit that is coupled to the core level shifter circuit and generates a second transient voltage applied to the core level shifter circuit when the input signal transitions from a high value to a low value.