The HEF4052BP is a dual 4-channel Analogue Multiplexer or Demultiplexer with common channel select logic. It has four independent inputs/outputs (nY0 to nY3) and a common input/output (nZ). The common channel select logic includes two select inputs (S1 and S2) and an active low enable input (E). Both multiplexers/demultiplexers contain four bi-directional analogue switches, each with one side connected to an independent input/output (nY0 to nY3) and the other side connected to a common input/output (nZ). With E low, one of the four switches is selected (low-impedance ON-state) by S1 and S2. With E high, all switches are in the high-impedance OFF-state, independent of S1 and S2. If break before make is needed, then it is necessary to use the enable input.