HD74LS251
1 of 8 Data Selector / Multiplexer (with strobe and three-state outputs)
REJ03D0467–0300 Rev.
3.
00
Jul.
15.
2005
This data selector / multiplexer contains full on-chip binary decoding to select one-of-eight data sources and features a strobe-controlled 3-state output.
The strobe must be at a low logic level to enable this device.
The 3-state outputs permit a number of outputs to be connected to a common bus.
When the strobe input is high, both outputs are in a high-impedance 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 oper...