A multi-level signal transmitter includes a voltage selection circuit, which is configured to select one amongst a plurality of driving voltages, which have different voltage levels, in response to input data including at least two bits of data therein. A driver circuit is also provided, which is configured to generate an output data signal as a multi-level signal, in response to the selected one of the plurality of driving voltages. This selected signal is provided as a body bias voltage to at least one transistor within the driver circuit. This driver circuit may include a totem-pole arrangement of first and second MOS transistors having respective first and second body bias regions therein, and at least one of the first and second body bias regions may be responsive to the selected one of the plurality of driving voltages.