The SY100S370 is a universal demultiplexer/decoder that can be used as either a dual 1-of-4 decoder or as a single 1-of-8 decoder and is designed for use in highperformance ECL systems. The Mode control (M) input determines the function. In the dual 1-of-4 mode, each 4input group has a pair of active-LOW Enable (E) inputs. The Enable pins are assigned such that in the single 1-of8 mode they can be tied together in pairs to result in two active-LOW Enable inputs. E1a will be tied to E1b and E2a to E2b.