74LS251 DIP 8-Line to 1-Line Data Selector/Multiplexer with 3-State Outputs
The 74LS251 is a high speed TTL integrated circuit that functions as a 1-of-8 data selector or multiplexer. It features three binary select inputs (S0, S1, S2) that determine which one of the eight individual data inputs (D0–D7) is routed to the output. A critical feature of this device is its 3-state output capability, which allows the output to be placed in a high-impedance state when the output enable (OE) is high, making it ideal for bus-oriented system architectures.
The IC provides both true (Y) and complementary (W) outputs, offering maximum flexibility for system logic and signal routing. The 74LS251 is widely used for data routing, signal multiplexing, and as a function generator for complex boolean logic. Because the outputs can be disconnected from the bus, multiple 74LS251 units can be connected to a common data line without the need for additional gates, facilitating the creation of larger multiplexers or data distribution networks.
KEY FEATURES
- 8-channel to 1-channel data selection and multiplexing
- 3-state outputs for direct connection to system buses
- Provides both true (Y) and complementary (W) outputs
- Binary select inputs for easy digital control
- Low power Schottky technology for high speed and efficiency
- Standard 16 pin dual in line package
SPECIFICATIONS
- Supply Voltage 4.75V to 5.25V
- Operating Temperature 0 to 70 Celsius
- Logic Type TTL Low Power Schottky
- Typical Propagation Delay 17ns
- High Level Output Current -2.6mA
- Low Level Output Current 24mA
- Input Voltage High 2.0V Minimum
INTERFACES
- D0 to D7 Data inputs
- S0 S1 S2 Binary select inputs
- OE BAR Output enable input active low
- Y True data output
- W Complementary data output
- VCC Positive supply voltage
- GND Ground reference
