According to one embodiment, an apparatus comprises a differential signaling bus, a tristate transmitter connected with the differential signaling bus, the tristate transmitter configured to provide a signal on the differential signaling bus responsive to a corresponding control signal, a receiver, a pair of differential inputs of the receiver connected with the differential signaling bus and configured to receive the signal from the differential signaling bus, and a termination circuit configured to couple a first differential input of the pair of differential inputs to a first voltage source and to couple a second differential input of the pair of differential inputs to a second voltage source, wherein the first and second voltage sources have different voltage levels.