When the EN pin of the TMUX1308-Q1 is pulled low, one of the switches is closed based on the state of the address lines. Similarly, when the EN pin of the TMUX1309-Q1 is pulled low, two of the switches are closed based on the state of the address lines. When the EN pin is pulled high, all the switches are in an open state regardless of the state of the address lines.

Unused logic control pins must be tied to GND or V_DD so that the device does /not consume additional current as highlighted in Implications of Slow or Floating CMOS Inputs. Unused signal path inputs (Sx and Dx) should be connected to GND.