HEF4539B Overview
The HEF4539B is a dual 4-input multiplexer with mon select logic. Each multiplexer has four multiplexer inputs (I0 and I3), an active LOW enable input (E) and a multiplexer output (O). When HIGH, E forces O of the respective multiplexer LOW, independent of the select inputs (S0 to S1) and I0 to I3.