Overview
The SN74AHCT125DRE4 is a quadruple bus buffer gate produced by Texas Instruments. This device features independent line drivers with 3-state outputs, making it versatile for various digital signal processing applications. Each buffer has its own output-enable (OE) input, allowing for individual control of each output. When the OE input is low, the buffer passes the data from the A input to its Y output, and when the OE input is high, the output is in a high-impedance state. This functionality is particularly useful in applications requiring signal isolation or multiplexing.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC Supply Voltage | 4.5 | 5.5 | V | |
| VIH High-Level Input Voltage | 2 | 2 | V | |
| VIL Low-Level Input Voltage | 0.8 | 0.8 | V | |
| VOH High-Level Output Voltage (IOH = -50 μA) | 4.4 | 4.5 | V | |
| VOL Low-Level Output Voltage (IOL = 8 mA) | 0 | 0.8 | V | |
| IOH High-Level Output Current | -8 | -8 | mA | |
| IOL Low-Level Output Current | 8 | 8 | mA | |
| TA Operating Free-Air Temperature | -40 | 125 | °C | |
| tPLH Propagation Delay Time (A to Y) | 3.8 | 5.5 | 6.5 | ns |
| tPHL Propagation Delay Time (A to Y) | 3.8 | 5.5 | 6.5 | ns |
Key Features
- Inputs are TTL-voltage compatible, allowing for seamless integration with TTL logic systems.
- Each buffer has its own output-enable (OE) input, enabling individual control of each output.
- 3-state outputs, which can be set to high impedance when the OE input is high.
- Latch-up performance exceeds 250 mA per JESD 17, ensuring robust operation against latch-up conditions.
- Operating supply voltage range of 4.5 V to 5.5 V, making it suitable for a variety of digital systems.
Applications
- Enable or disable digital signals in various applications.
- Control indicator LEDs by buffering and isolating the signal.
- Debounce switches to eliminate noise and ensure stable input signals.
- Eliminate slow or noisy input signals by buffering them.
- Act as a multiplexer to select specific data lines depending on the pin function selected on a microcontroller.
Q & A
- What is the primary function of the SN74AHCT125DRE4?
The primary function is to act as a quadruple bus buffer gate with 3-state outputs, allowing for individual control of each buffer.
- What is the operating supply voltage range for the SN74AHCT125DRE4?
The operating supply voltage range is from 4.5 V to 5.5 V.
- How do the output-enable (OE) inputs work?
When the OE input is low, the buffer passes the data from the A input to its Y output. When the OE input is high, the output is in a high-impedance state.
- What is the significance of TTL-voltage compatible inputs?
TTL-voltage compatible inputs allow the device to seamlessly integrate with TTL logic systems.
- What is the latch-up performance of the SN74AHCT125DRE4?
The latch-up performance exceeds 250 mA per JESD 17.
- What are some common applications of the SN74AHCT125DRE4?
Common applications include enabling or disabling digital signals, controlling indicator LEDs, debouncing switches, and eliminating slow or noisy input signals.
- How can the SN74AHCT125DRE4 be used in multiplexing applications?
The device can act as a multiplexer to select specific data lines depending on the pin function selected on a microcontroller.
- What is the maximum load capacitance the SN74AHCT125DRE4 can drive?
The device can drive a load with a total capacitance less than or equal to 50 pF while meeting all data sheet specifications.
- What are the thermal characteristics of the SN74AHCT125DRE4?
The device has various thermal metrics depending on the package type, such as θJA (junction-to-ambient thermal impedance) ranging from 76 to 147.7 °C/W.
- How should unused inputs be handled to ensure proper device operation?
All unused inputs must be held at VCC or GND to ensure proper device operation.
