The 74125 is a high-speed, quad bus buffer gate featuring 3-state outputs. This integrated circuit belongs to the 7400 series of TTL logic devices and is designed to provide high-performance buffering for digital systems. Each of the four buffers is controlled by an independent output enable input, allowing for flexible bus interfacing and signal isolation.
This component is particularly useful in bus-oriented systems where multiple devices need to share a common bus without interference. The 3-state outputs provide high impedance when disabled, effectively disconnecting the buffer from the bus. The 74125 is characterized for operation over a wide temperature range and is available in multiple package options.
The 74125 finds application in various digital systems where bus buffering and signal isolation are required:
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (VCC) | 7 | V |
| Input Voltage | 5.5 | V |
| Output Voltage (High State) | 5.5 | V |
| Operating Free Air Temperature Range | 0 to +70 | °C |
| Storage Temperature Range | -65 to +150 | °C |
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage (VCC) | 4.75 | 5.0 | 5.25 | V |
| High-Level Input Voltage | 2.0 | - | - | V |
| Low-Level Input Voltage | - | - | 0.8 | V |
| Operating Ambient Temperature | 0 | - | 70 | °C |
| Parameter | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| High-Level Output Voltage | VCC = Min, IOH = -400µA | 2.4 | 3.4 | - | V |
| Low-Level Output Voltage | VCC = Min, IOL = 16mA | - | 0.2 | 0.4 | V |
| Input Clamp Voltage | VCC = Min, II = -18mA | - | -1.5 | - | V |
| High-Level Input Current | VCC = Max, VI = 2.7V | - | 40 | µA | |
| Low-Level Input Current | VCC = Max, VI = 0.4V | - | -1.6 | mA |
| Parameter | Test Conditions | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Propagation Delay (A to Y) | VCC = 5V, CL = 15pF | - | 8 | 15 | ns |
| Output Enable Time (OE to Y) | VCC = 5V, CL = 15pF | - | 12 | 22 | ns |
| Output Disable Time (OE to Y) | VCC = 5V, CL = 15pF | - | 15 | 25 | ns |
The 74125 is available in several package options to accommodate different application requirements: