SN74HCT139D

The SN74HCT139D Encoder/Decoder/Multiplexer/Demultiplexer manufactured by Texas Instruments is a high-speed CMOS device with dual 2-of-4 line encoding/decoding logic levels. It features four active low active-high control inputs that can be used together to select one of four data lines as an output. It is designed to operate in both logic high and low voltage range and it has an operating supply voltage of 4.5 – 5.5V. It also has output enable pins that can be used for either active low enable or active high enable. The SN74HCT139D is perfect for various applications such as keyboard scanning or memory decoding.