An embodiment of a transmitter includes an amplifier having first and second differential output nodes, a first supply node, a first pull-up impedance having a first node coupled to the first differential output node and having a second node coupled to the supply node, and a second pull-up impedance having a first node coupled to the second differential output node and having a second node coupled to the supply node. An embodiment of a receiver includes an amplifier having first and second differential input nodes, a first supply node, a first pull-up impedance having a first node coupled to the first differential input node and having a second node coupled to the supply node, and a second pull-up impedance having a first node coupled to the second differential input node and having a second node coupled to the supply node. In an embodiment, the transmitter and receiver are capacitively coupled to one another.