Driver circuit for an attachment unit interface used in a network system

A driver circuit for an attachment unit interface used in a network system, said network system providing complementary data signals and an enable signal to said driver circuit, the driver circuit comprising:

• a constant current source;
• a differential transistor pair including a pair of differential transistors and a pair of load resistors, each of said differential transistors having a gate terminal which receives one of said complementary data signals, a drain terminal which is connected to one of said load resistors, and a source terminal which is connected to said constant current source;
• a switch network connected to said drain terminal of said differential transistors and activated by said enable signal so as to generate a differential voltage output;
• a pair of source followers, each having a gate terminal connected to said switch network and a source terminal, said source followers receiving said differential voltage output from said switch network;
• and
• a switching transistor having a gate terminal which receives said enable signal, and source and drain terminals which are connected to said source terminal of a respective one of said source followers and which are further connected to a respective external pull-down load resistor, said source and drain terminals of said switching transistor to be connected to said attachment unit interface.