the cd4067 is a 16-channel analog multiplexer/demultiplexer with four address inputs (a0 to a3), an active low enable input (e), sixteen independent inputs/outputs (y0 to y15) and a common input/output (z). the device contains sixteen bidirectional analog switches, each with one side connected to an independent input/output (y0 to y15) and the other side connected to the common input/output (z). withe low, one of the sixteen switches is selected (low-impedance on-state) by a0 to a3. all unselected switches are in the high-impedance off-state. withe high all switches are in the high-impedance off-state, independent of a0 to a3. the analog inputs/outputs (y0 to y15 and z) can swing between vdd as a positive limit and vss as a negative limit. vdd to vss may not exceed 9v.