74LS251 is a high speed 8-Input Digital Multiplexer. These ICs contain full on-chip binary decoding to select one of eight data sources and feature a strobe-controlled three-state output. The strobe must be at a low logic level to enable these devices. The three-state outputs permit a number of outputs to be connected to a common bus. The output of the IC always comes in TTL which makes it easy to work with other TTL devices and microcontrollers. The IC also constitutes a wide array of features such as thermal overload protection & ESD protection. The IC 74LS251 is smaller in size and it has a much faster speed which makes it reliable in every kind of device.
What is a Data Selector/Multiplexer?
A multiplexer/data selector is a digital combinational logic circuit that toggles one of several input lines to a single common output line. The select lines determine which input is connected to the output, and also to increase the amount of data that can be sent over a network within a certain time. It is also called a data selector.
74LS251 Pinout
74LS251 Pin Configuration
| Pin No | Pin Name | Description |
|---|---|---|
| 1 | I3 | Multiplexer Input I3 |
| 2 | I2 | Multiplexer Input I2 |
| 3 | I1 | Multiplexer Input I1 |
| 4 | I0 | Multiplexer Input I0 |
| 5 | Z | Multiplexer Output Z |
| 6 | Z’ | Complementary Multiplexer Output Z’ |
| 7 | E0′ | Active Low Output Enable Input |
| 8 | GND | Ground Pin |
| 9 | S2 | Data Select Input S2 |
| 10 | S1 | Data Select Input S1 |
| 11 | S0 | Data Select Input S0 |
| 12 | I7 | Multiplexer Input I7 |
| 13 | I6 | Multiplexer Input I6 |
| 14 | I5 | Multiplexer Input I5 |
| 15 | I4 | Multiplexer Input I4 |
| 16 | Vcc | Chip Supply Voltage |
74LS251 Features & Specifications
- Technology Family: LS
- Function: Encoder, Multiplexer
- Configuration: 8:1
- Channels (#): 1
- VCC (Min) (V): 4.75
- VCC (Max) (V): 5.25
- Input type: TTL
- Output type: TTL
- Tri-State Version of the 74LS151
- Interface Directly with the System Bus
- Perform Parallel to Serial Conversion
- Complementary Outputs Provide True and Inverted Data
- Standard TTL Switching Voltages
Applications
- The 74LS251 IC can be used as a universal function generator to generate any logic function of fosur variables.
- Sometimes also used to encode the output of a flash analog to digital converter.
You can download this Datasheet for 74LS251 8 To 1 Data Selector/Multiplexer from the link given below:
See Also: 74LS93 4-Bit Binary/Decade Counter IC – Datasheet | 74LS14 Schmitt Trigger Hex Inverter IC – Datasheet | 74LS04 Hex Inverter IC / NOT Gate IC – Datasheet
