Home > Microcontrollers & Processors > Digital Signal Processors (DSP) > 74HC245D

74HC245D

Octal bus transceiver, bidirectional, 3-state, SOIC-20

5000

Effective Inventory

Go to Inquiry

Image for reference only

Manufacturer Part：

74HC245D

Package：

SOIC-20 / SOT163-1 (12.8×7.5×2.65 mm, 1.27mm pitch)

Description

Product Overview

The 74HC245D from Nexperia is an octal bidirectional bus transceiver with 3-state outputs in an SOIC-20 package. It features an output enable (OE, active-LOW) and direction control (DIR) for bidirectional data flow between two 8-bit buses. With ±7.8 mA output drive, CMOS low power, and non-inverting 3-state outputs, it is the standard choice for bus interfacing and bidirectional data communication.

Key Specifications

Logic Function	Octal bus transceiver, 3-state
Supply Voltage	2.0V to 6.0V
Propagation Delay	10 ns typical @ 5V
Output Drive	±7.8 mA @ 5V
Direction Control	DIR pin (A→B or B→A)
Output Enable	OE pin (active-LOW)
Max Frequency	36 MHz
Input Levels	CMOS (74HC245)
Operating Temperature	-40°C to +125°C
Package	SOIC-20 (SOT163-1, 12.8×7.5 mm)

Features

Octal bidirectional bus interface with 3-state outputs
Direction control (DIR): A-to-B or B-to-A
Output enable (OE, active-LOW) for bus isolation
Non-inverting outputs
±7.8 mA output drive at 5V
Input clamp diodes for overvoltage interface
CMOS low power dissipation

Applications

Microprocessor/microcontroller bus interfacing
Bidirectional data bus communication
Memory and I/O bus buffering and isolation
Level translation between mixed-voltage buses

Product Introduction:74HC245D Product Introduction

The 74HC245D from Nexperia is an octal bidirectional bus transceiver with 3-state outputs in an SOIC-20 package. With DIR direction control and OE output enable, ±7.8 mA drive, and CMOS low power, it is the standard choice for microprocessor bus interfacing, bidirectional data communication, and memory I/O bus buffering.

Working Principle:74HC245D Working Principle

The 74HC245D provides bidirectional data transfer between two 8-bit buses (A and B). The DIR pin controls the data flow direction: when DIR is HIGH, data flows from A to B; when DIR is LOW, data flows from B to A. The OE pin (active-LOW) controls the output enable: when OE is HIGH, all outputs enter high-impedance state, effectively isolating the two buses. When OE is LOW, data flows in the direction selected by DIR. The eight transceiver channels are non-inverting and provide 3-state outputs for bus sharing. Multiple 74HC245Ds can share a common bus using OE-based arbitration. The input clamp diodes protect against voltages exceeding VCC.

Pin Description:74HC245D Pin Definition and Functions

Pin	Name	Type	Function
1	DIR	Input	Direction control (HIGH=A→B, LOW=B→A)
2-9	A0-A7	I/O	Bus A data (bidirectional)
10	GND	Power	Ground (0V)
11-18	B0-B7	I/O	Bus B data (bidirectional)
19	OE	Input	Output enable (active LOW)
20	VCC	Power	Supply voltage (2.0-6.0V)

Application Scenarios:In which products and applications is74HC245D used

Microprocessor/microcontroller bidirectional bus interfacing
Data bus communication between subsystems
Memory and I/O bus buffering and isolation
Level translation between mixed-voltage buses

Alternative Models:What chips are recommended as replacements for 74HC245D

Manufacturer	Part Number	Package	Notes
Nexperia	74HCT245D	SOIC-20	TTL input levels (4.5-5.5V)
TI	SN74HC245DW	SOIC-20	Functionally equivalent
ON Semi	MC74HC245ADWR2G	SOIC-20	Functionally equivalent
Nexperia	74HC245PW	TSSOP-20	Smaller footprint
Nexperia	74HC640D	SOIC-20	Inverting transceiver version