The 74F251A is a logic implementation of a single 8-position switch with the switch position controlled by the state of three Select (S0, S1, S2) inputs. True (Y) and complementary (Y) outputs are both provided. The output enable (OE) is active Low. When OE is High, both outputs are in High impedance state, allowing multiple output connections to a common bus without driving nor loading the bus significantly. All but one device must be in High impedance state to avoid high currents that would exceed the maximum ratings when the outputs of the 3-State devices are tied together. When the output of more than one device is tied together the user must ensure that there is no overlap in the active Low portion of the output enable voltages.