© 2005 Fairchild Semiconductor Corporation

DS005165

www.fairchildsemi.com

September 1983

Revised May 2005

MM74HC245A

Octal 3-STATE Transceiver

General Description

The MM74HC245A 3-STATE bidirectional buffer utilizes

advanced silicon-gate CMOS technology, and is intended

for two-way asynchronous communication between data

buses. It has high drive current outputs which enable high

speed operation even when driving large bus capaci-

tances. This circuit possesses the low power consumption

and high noise immunity usually associated with CMOS cir-

cuitry, yet has speeds comparable to low power Schottky

TTL circuits.

This device has an active LOW enable input G and a direc-

tion control input, DIR. When DIR is HIGH, data flows from

the A inputs to the B outputs. When DIR is LOW, data flows

from the B inputs to the A outputs. The MM74HC245A

transfers true data from one bus to the other.

This device can drive up to 15 LS-TTL Loads, and does not

have Schmitt trigger inputs. All inputs are protected from

ground.

Features

■ Typical propagation delay: 13 ns

■ Wide power supply range: 2–6V

■ Low quiescent current: 80

PA maximum (74 HC)

■ 3-STATE outputs for connection to bus oriented systems

■ High output drive: 6 mA (minimum)

■ Same as the 645

Ordering Code:

Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.

Connection Diagram

Pin Assignments for DIP, SOIC, SOP and TSSOP

Top View

Truth Table

H

HIGH Level

L

LOW Level

X

Irrelevant

Order Number

Package Number

Package Description

MM74HC245AWM

M20B

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide

MM74HC245ASJ

M20D

20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide

MM74HC245AMTC

MTC20

20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide

MM74HC245AN

N20A

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide

Control

Inputs

Operation

G

DIR

L

L

B data to A bus

L

H

A data to B bus

HX

Isolation