Abstract: An output circuit is provided for obtaining an output signal at one of two voltages regardless of the relative difference between the voltage levels. The output circuit includes a first switching circuit that contains two current sources for selectively producing one of two constant currents. A second switching circuit receives one of the two constant currents. The first and second switches are connected by four series-connected forward biased diodes. There are also bypass connectors for selectively providing current around the first and fourth diodes. An output terminal is located between the second and third diodes. A high voltage source is located between the first switching circuit and the first diode. A low voltage source is located between the fourth diode and the second switching circuit. Depending which of the current sources are actuated, the signal present at the output terminal is either that of the high voltage source or that of the low voltage source.