1 Features

• Operating voltage range of 4.5V to 5.5V

• TTL-compatible inputs

• Continuous ±24mA output drive at 5V

• Supports up to ±75mA output drive at 5V

in short bursts

• Drives 50Ω transmission lines

• Fast operation with delay of 10.2ns max

2 Applications

• Memory device selection with shared data bus

• Reduce required number of outputs for chip select

applications

• Route data

3 Description

The SN74ACT139 contains two two-to-four decoders

with one active low output strobe (G). When the

strobe input is inactive (G = HIGH), the outputs for

that channel are all forced into the high state. When

strobe input is active (G = LOW), only the selected

output is low while all others are high.