The MC74AC139/74ACT139 is a high–speed, dual 1–of–4 decoder/demultiplexer. The device has two independent decoders, each accepting two inputs and providing four mutually–exclusive active–LOW outputs. Each decoder has an active–LOW Enable input which can be used as a data input for a 4–output demultiplexer. Each half of the MC74AC139/74ACT139 can be used as a function generator providing four minterms of two variables.

• Multifunctional Capability

• Two Completely Independent 1–of–4 Decoders

• Active LOW Mutually Exclusive Outputs

• Outputs Source/Sink 24 mA

• ′ACT139 Has TTL Compatible Inputs

74AC139属于集成电路（IC） > 信号开关，多路复用器，解码器。安森美半导体公司制造生产的74AC139信号开关，多路复用器，解码器逻辑型信号开关、多路复用器和编码器 IC 可用于对以数字格式表示数据的电信号进行路由和选择。这些器件与设计用于模拟信号的类似产品有所不同，它们保留的信息表示为两个电状态之一，而不是两个外部界限内的无穷变化量。