The 74LS series of integrated circuits (ICs) was one of the most popular logic families of transistor-transistor logic (TTL) logic chips. 74LS series is a bipolar, low-power Schottky IC. 74LS126 bus buffers feature three-state outputs that, when enabled, have the low impedance characteristics of a TTL output with additional drive capability at high logic levels to permit driving heavily loaded bus lines without external pullup resistors.

74LS126 Features
- Four Independent Non-Inverting Buffer Gates
- Enabled Mode
- Fast Switching Times
- Operating Temperature up to 70°C
- Standard TTL Switching Voltages
74LS126 Specifications
Supply Voltage | 4.75 – 5.25Vdc |
Maximum Clock Frequency | 40Mhz |
Power Dissipation | 2mW/gate @100kHz |
Minimum Output Current | 8mA |
Propagation Delay | 10nS |
Fan Out (TTL Loads) | 20 |
74LS126 Pinout Diagram

74LS126 Pin Description
Pin No | Pin Name | Description |
1 | 1G, 1G*’ | LOW/High pin of Buffer 1 |
2 | 1A | Input Of Buffer 1 |
3 | 1Y | Output Of Buffer 1 |
4 | 2G,2G*’ | LOW/High pin of Buffer 2 |
5 | 2A | Input Of Buffer 2 |
6 | 2Y | Output Of Buffer 2 |
7 | GND | Ground |
8 | 3Y | Output Of Buffer 3 |
9 | 3A | Input Of Buffer 3 |
10 | 3G,3G*’ | LOW/High pin of Buffer 3 |
11 | 4Y | Output Of Buffer 4 |
12 | 4A | Input Of Buffer 4 |
13 | 4G,4G*’ | LOW/High pin of Buffer 4 |
14 | VCC | Positive Supply |
74LS126 Circuit
Applications
- A digital buffer (or a voltage buffer) is an electronic circuit element used to isolate input from the output.
74LS126 Alternative Equivalent
74LS125, 74ls367
Download 74LS126 Quad Bus Buffer Tri-State Datasheet from the link given below.