A control terminal driver IC for a switching circuit having series connected high and low side output transistors, an associated split power supply and a floating input, the gate drive IC, an exemplary, but non-limiting, example of which is a Class D audio amplifier. The IC includes an input circuit, a voltage to current converter connected to the input circuit, a level shifter formed in a mid well of the IC, which is operative to transfer the input signal to the low side without the need for a power supply input to the mid well, a current to voltage converter on the low side coupled to the level shifter; and an output circuit which is operative to generate control terminal drive signals for the high and low side transistors.