DM74LS251N
数据手册.pdf3 - STATE 1 - 8线数据选择器/多路复用器 3-STATE 1-of-8 Line Data Selector/Multiplexer
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
Features
■3-STATE version of DM74LS151
■Interface directly with system bus
■Perform parallel-to-serial conversion
■Permit multiplexing from N-lines to one line
■Complementary outputs provide true and inverted data
■Maximum number of common outputs: 129
■Typical propagation delay time D to Y: 17 ns
■Typical power dissipation: 35 mW