Dual 2-to-4 line decoder/demultiplexer

The 74LVC139 decodes two binary weighted address inputs (nA0, nA1) to four mutually exclusive outputs (nY0 to nY3). Each decoder features an enable input (nE). When nE is HIGH all outputs are forced HIGH. The enable input can be used as the data input for a 1-to-4 demultiplexer application. Inputs can be driven from either 3.3 V or 5 V devices. This feature allows the use of these devices as translators in mixed 3.3 V and 5 V environments.

Schmitt-trigger action at all inputs makes the circuit tolerant of slower input rise and fall times.