74HC125D

The 74HC125D is a specific variant of the 74HC125 quad buffer/line driver with 3-state outputs, belonging to the 74HC logic family. Here’s a breakdown of its key features:

• Function:

  • Buffering: Amplifies the input signal while maintaining its logic state (no inversion), isolating the input from other parts of the circuit and improving signal integrity.
  • Line Driving: Increases the current driving capability of a signal, allowing it to drive multiple outputs or long wires without signal degradation.
  • 3-State Outputs: Each output can be set to a high-impedance state (disconnected), a high logic level, or a low logic level, enabling features like data bus sharing or output isolation.

• Logic Family: 74HC – Uses high-speed CMOS technology, offering good noise immunity and relatively low power consumption.

• Number of Buffers: Four independent buffers within a single IC package.

• Input/Output Count:

  • Four data input pins (A1-A4)
  • Four data output pins (Y1-Y4)
  • One output enable pin (nOE) for all outputs

Additional Features of 74HC125D:

• Wide Supply Voltage Range: Typically operates between 2.0V and 6.0V, offering flexibility in circuit design.
• CMOS Low Power Dissipation: Consumes less power compared to older logic families like TTL.
• ESD Protection: Protects the IC from electrostatic discharge (ESD) events.

Applications:

• Similar to the general 74HC125: buffering signals, data bus transceivers, level shifting (limited), signal gating.

Important Note:

• Active-Low Output Enable (nOE): In the 74HC125D, the output enable pin (nOE) is active-low. This means that a low signal on nOE enables the outputs (Y1-Y4), allowing them to drive high or low logic levels based on the corresponding data inputs (A1-A4). Conversely, a high signal on nOE puts the outputs in a high-impedance state (disconnected).

Resources:

• You can find the datasheet for the 74HC125D online at various electronics component distributors or websites like:
  • Nexperia: https://www.nexperia.com/products/analog-logic-ics/logic/buffers-inverters-transceivers/buffers/series/74HC125-74HCT125.html
  • Alldatasheet (may include datasheets from various manufacturers): https://www.alldatasheet.com/

The resources above provide detailed specifications, pin configuration, truth table, and other relevant information for the 74HC125D.