onsemi MC74AC05DG Hex Inverter IC: Datasheet, Application Circuit, and Pinout Configuration

The MC74AC05DG from onsemi is a member of the advanced high-speed CMOS (AC) logic family, integrating six independent open-drain inverter gates into a single compact package. This IC is designed for 2.0V to 6.0V operation, making it suitable for interfacing between different voltage level systems and for wired-AND applications. Its open-drain outputs require an external pull-up resistor to function, providing significant design flexibility.

Pinout Configuration

The MC74AC05DG is housed in a 14-pin SOIC package. The pinout is standardized for hex inverter ICs:

Pins 1, 3, 5, 9, 11, 13 (Inputs): The inputs to the six individual inverters (1A through 6A).

Pins 2, 4, 6, 8, 10, 12 (Outputs): The corresponding open-drain outputs (1Y through 6Y).

Pin 7 (GND): Ground (0V reference).

Pin 14 (VCC): Positive supply voltage pin (typically +5V).

Key Datasheet Specifications

Critical parameters from the datasheet define the IC's performance and operating limits:

Logic Family: 74AC

Supply Voltage Range (VCC): 2.0V to 6.0V

Output Type: Open-Drain

High-Level Output Current (IOH): -24 mA (with external pull-up)

Low-Level Output Current (IOL): 24 mA (sink current)

Propagation Delay (tPD): Typically 7.5 ns at 5V

Operating Temperature Range: -40°C to +85°C

Application Circuit

A fundamental application of the open-drain output is level shifting. For example, to interface a 3.3V logic signal to a 5V system:

1. The input (e.g., 1A) is driven by the 3.3V logic signal.

2. The open-drain output (1Y) is connected to a pull-up resistor (e.g., 10kΩ) tied to the 5V supply rail.

3. When the input is LOW, the internal MOSFET is ON, pulling the output LOW (near 0V).

4. When the input is HIGH, the internal MOSFET is OFF, allowing the external pull-up resistor to pull the output HIGH to 5V.

This simple circuit effectively translates the logic level from 3.3V to 5V. Furthermore, multiple open-drain outputs can be tied together to a single pull-up resistor, creating a wired-AND configuration, which is useful for bus structures and interrupt lines.

ICGOODFIND Summary

The onsemi MC74AC05DG is a highly versatile hex inverter IC whose open-drain outputs are its defining feature. It excels in applications requiring level translation, wired-AND logic, and interface buffering. Its wide operating voltage range and robust output sink current capability make it a reliable and flexible component for a vast array of digital design projects.

Keywords: Open-Drain, Level Shifting, Hex Inverter, 74AC Logic, Wired-AND