a cmos output cell with multiple output modes is disclosed . in one embodiment , the cell drives a differential output signal on two output pads in one mode and two single - ended output signals on the two output pads in another mode . differential and single - ended driver transistors are included for this purpose . a logic circuit disables unused driver transistors , and supplies appropriate drive signals to those transistors for each mode . when disabled , the driver transistors serve an electrostatic discharge protection function , at least partially alleviating the need for esd - specific devices in the cell . the diminished need for esd - specific devices allows the cell to offer a highly flexible chip interface , with little or no increase in circuit area over a conventional cell that offers only single - ended or differential output .