The 100370 universal demultiplexer/decoder functions as either a dual 1-of-4 decoder or as a single 1-of-8 decoder, depending on the signal applied to the Mode Control (M) input. In the dual mode, each half has a pair of active-LOW Enable (E) inputs. Pin assignments for the E inputs are such that in the 1-of-8 mode they can easily be tied together in pairs to provide two active-LOW enables (E1a to E1b, E2a to E2b). Signals applied to auxiliary inputs Ha, Hb and Hc determine whether the outputs are active HIGH or active LOW. In the dual 1-of-4 mode the Address inputs are A0a, A1a and A0b,