onsemi MC74HCT365ADR2G Hex Buffer/Line Driver: Datasheet, Pinout, and Application Circuit Guide

The MC74HCT365ADR2G from onsemi is a high-speed, high-performance hex buffer and line driver integrated circuit belonging to the popular 74HCT family. This device is engineered to provide robust signal conditioning, voltage level shifting, and increased drive capability in a wide array of digital systems. Its high-noise-immunity characteristics and TTL-compatible inputs make it an ideal choice for interfacing between different logic families and driving heavy loads, such as buses and transmission lines.

This guide provides a detailed overview of its datasheet specifications, pinout configuration, and a practical application circuit to help engineers effectively integrate this component into their designs.

Datasheet Overview and Key Specifications

The MC74HCT365ADR2G is a hex non-inverting buffer with 3-state outputs. The "hex" denotes that it contains six independent buffers within a single 16-pin package. The "HCT" prefix indicates that it is fabricated with High-speed CMOS technology, offering the low power consumption of CMOS while maintaining compatibility with TTL input logic levels.

Key electrical characteristics from the datasheet include:

Operating Voltage: 4.5V to 5.5V, making it perfect for standard 5V systems.

Logic Family: 74HCT (High-Speed CMOS with TTL-compatible inputs).

Output Drive Capability: Can sink/sink up to ±35 mA at the output, providing strong current to drive multiple inputs or LEDs.

High Noise Immunity: Typical noise immunity of ~500 mV, ensuring reliable operation in electrically noisy environments.

3-State Outputs: Features an output enable (OE) input. When OE is held high, the outputs are placed in a high-impedance state (Hi-Z), allowing the device to be disconnected from a shared bus, which is critical for bus-oriented systems.

Package: The "D" in the part number signifies an SOIC-16 package, which is suitable for automated PCB assembly.

Pinout Configuration

Understanding the pinout is crucial for correct circuit design and PCB layout. The MC74HCT365ADR2G in the SOIC-16 package has the following pin configuration:

Pins 1, 3, 5, 9, 11, 13 (1A - 6A): These are the input pins for the six individual buffers.

Pins 2, 4, 6, 8, 10, 12 (1Y - 6Y): These are the corresponding non-inverting output pins.

Pin 15 (OE1): Output Enable input for buffers 1 through 3. Active LOW.

Pin 14 (OE2): Output Enable input for buffers 4 through 6. Active LOW.

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

Pin 16 (VCC): Positive supply voltage pin (typically +5V).

The dual output enable pins provide flexible control, allowing different banks of three buffers to be enabled independently.

Application Circuit Guide: 5V Microcontroller to LED Array Driver

A common application for the MC74HCT365ADR2G is to act as an interface between a low-current microcontroller (MCU) and a load requiring higher current. Here is a guide for building a simple 6-channel LED driver circuit.

Objective: To use a 5V MCU to power six LEDs brightly without overloading the MCU's GPIO pins.

Components Needed:

onsemi MC74HCT365ADR2G (IC1)

5V Microcontroller (e.g., Arduino, PIC, ARM)

6 x LEDs (LED1 - LED6)

6 x Current-limiting resistors (e.g., 220Ω, R1 - R6)

Power supply (5V)

Decoupling capacitor (0.1µF)

Circuit Connection:

1. Power: Connect VCC (Pin 16) to the +5V rail. Connect GND (Pin 7) to the common ground.

2. Enable: Tie both OE1 (Pin 15) and OE2 (Pin 14) to ground (GND) to permanently enable all six buffers. For bus applications, these would be connected to a control signal from the MCU.

3. Inputs: Connect the six MCU GPIO pins to the buffer inputs 1A through 6A (Pins 1, 3, 5, 9, 11, 13).

4. Outputs & LEDs: Connect each buffer output (1Y through 6Y) to the anode of an LED through a 220Ω current-limiting resistor. Connect the cathodes of all LEDs to ground.

5. Decoupling: Place a 0.1µF ceramic capacitor between the VCC and GND pins, close to the IC, to suppress high-frequency noise.

Operation: When an MCU GPIO pin is set to logic HIGH (5V), the corresponding buffer output also goes HIGH, lighting up the LED. The MC74HCT365ADR2G provides the necessary current (up to 35mA per output) to drive the LED brightly, while the MCU only needs to supply a minuscule amount of current into the high-impedance HCT input.

---

ICGOODFIND: The onsemi MC74HCT365ADR2G is a versatile and robust solution for signal buffering, voltage level translation, and high-current driving. Its 3-state outputs and high noise immunity make it indispensable in bus-based architectures and industrial applications. By following the pinout and application guidelines, designers can ensure signal integrity and improve the overall drive capability of their digital systems.

Keywords:

Hex Buffer

Line Driver

74HCT Logic

3-State Output

Level Shifting