Manufacturer | Part No. | Datasheet | Description |
 National Semiconductor ... | 74F257APC |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
 National Semiconductor ... | 74F257ASC |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
 National Semiconductor ... | 74F257ASCSCX |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
74F257ASCSJX |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
 National Semiconductor ... | 74F257ASJ |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
74F257ASJSCX |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |
74F257ASJSJX |  157Kb / 8P | Quad 2-Input Multiplexer with TRI-STATE Outputs |