A bidirectional interface apparatus, the apparatus comprising: a pair of terminals (305, 310) configured to electrically connect to a differential circuit; a pair of electrical nodes, each of the electrical nodes electrically coupled to a corresponding one of the pair of terminals (305, 310); a transmit driver circuit coupled to each of the pair of terminals (305, 310) via the pair of electrical nodes, wherein the transmit driver circuit comprises a plurality of slices, each slice in the plurality of slices comprising: (i) an output driver circuit (Q4-Q7); and, (ii) a programmable pre-driver circuit (U4-U7) coupled to selectively enable or disable the output driver circuit in the same slice in response to an enable signal, the programmable pre-driver circuit operable in a receive mode and a transmit mode, wherein, in the receive mode, the programmable pre-driver circuit is operable to apply a protective bias voltage to the control terminals of each of the transistors of the respective output driver circuit to protect the output driver circuits from voltage stress impartable by a receive signal that has a higher drive voltage than the safe operating specification of the transmit driver circuit, and, in the transmit mode, the programmable pre-driver circuit is selectively enabled, a receive buffer circuit coupled to each of the pair of terminals (305, 310) via the pair of electrical nodes; and, a control circuit coupled to the transmit driver circuit, wherein the control circuit is configured to determine one or more of the slices to selectively enable based on an output resistance of the transmit driver circuit and to generate the enable signal based on the one or more slices to enable. a pair of terminals (305, 310) configured to electrically connect to a differential circuit; a pair of electrical nodes, each of the electrical nodes electrically coupled to a corresponding one of the pair of terminals (305, 310); a transmit driver circuit coupled to each of the pair of terminals (305, 310) via the pair of electrical nodes, wherein the transmit driver circuit comprises a plurality of slices, each slice in the plurality of slices comprising: (i) an output driver circuit (Q4-Q7); and, (ii) a programmable pre-driver circuit (U4-U7) coupled to selectively enable or disable the output driver circuit in the same slice in response to an enable signal, the programmable pre-driver circuit operable in a receive mode and a transmit mode, wherein, in the receive mode, the programmable pre-driver circuit is operable to apply a protective bias voltage to the control terminals of each of the transistors of the respective output driver circuit to protect the output driver circuits from voltage stress impartable by a receive signal that has a higher drive voltage than the safe operating specification of the transmit driver circuit, and, in the transmit mode, the programmable pre-driver circuit is selectively enabled, (i) an output driver circuit (Q4-Q7); and, (ii) a programmable pre-driver circuit (U4-U7) coupled to selectively enable or disable the output driver circuit in the same slice in response to an enable signal, the programmable pre-driver circuit operable in a receive mode and a transmit mode, wherein, in the receive mode, the programmable pre-driver circuit is operable to apply a protective bias voltage to the control terminals of each of the transistors of the respective output driver circuit to protect the output driver circuits from voltage stress impartable by a receive signal that has a higher drive voltage than the safe operating specification of the transmit driver circuit, and, in the transmit mode, the programmable pre-driver circuit is selectively enabled, a receive buffer circuit coupled to each of the pair of terminals (305, 310) via the pair of electrical nodes; and, a control circuit coupled to the transmit driver circuit, wherein the control circuit is configured to determine one or more of the slices to selectively enable based on an output resistance of the transmit driver circuit and to generate the enable signal based on the one or more slices to enable.