The SN74HC139DR with Encoders, Decoders, Multiplexers & Demultiplexers is a dual 2 to 4-line decoder/demultiplexer manufactured by Texas Instruments. It is a logic signal device capable of transforming two binary logic level inputs into four independent output lines. It is commonly used in logic-level translation and signal switching applications, such as multiplexers or decoders. The output level of the device is determined by the logic levels of the input signals supplied. The device is manufactured with either the SN74HC139 or the SN74HC139A logic chip series, and operates over a wide range of voltages, from 2.0V to 6.0V. With an active LOW enable input, the device is capable of decoding two binary coded inputs to four output lines, while the active HIGH enable input functions as a data select input to demultiplex two address inputs into four outputs. It also provides a common output enable (OE) for quick disabling or enabling of all output lines.