General Description

These data selectors/multiplexers contain full on-chip

binary decoding to select one-of-eight data sources, and

feature a strobe-controlled 3-STATE output. The strobe

must be at a low logic level to enable these devices. The 3-

STATE outputs permit direct connection to a common bus.

When the strobe input is HIGH, both outputs are in a highimpedance

state in which both the upper and lower transistors

of each totem-pole output are OFF, and the output neither

drives nor loads the bus significantly. When the strobe

is LOW, the outputs are activated and operate as standard

TTL totem-pole outputs.

To minimize the possibility that two outputs will attempt to

take a common bus to opposite logic levels, the output control

circuitry is designed so that the average output disable

time is shorter than the average output enable time.

Features

n 3-STATE version of DM74LS151

n Interface directly with system bus

n Perform parallel-to-serial conversion

n Permit multiplexing from N-lines to one line

n Complementary outputs provide true and inverted data

n Maximum number of common outputs: 129

n Typical propagation delay time (D to Y): 17 ns

n Typical power dissipation: 35 mW