These data selectors/multiplexers contain full binary decoding to select one of eight data sources and feature strobe-controlled complementary outputs. The 3-state outputs can interface with and drive data lines of bus-organized systems. When the strobe (G\) 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.

The SN54F251B is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74F251B is characterized for operation from 0°C to 70°C.