MM74HCT245 Octal 3-STATE Transceiver
February 1984
Revised February 1999
MM74HCT245
Octal 3-STATE Transceiver
General Description
The MM74HCT245 3-STATE bi-directional 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
of CMOS circuitry, yet has speeds comparable to low
power Schottky TTL circuits.
This device is TTL input compatible and can drive up to 15
LS-TTL loads, and all inputs are protected from damage
due to static discharge by diodes to V
CC
and ground.
The MM74HCT245 has one active low enable input (G),
and a direction control (DIR). When the DIR input is HIGH,
data flows from the A inputs to the B outputs. When DIR is
LOW, data flows from B to A.
MM74HCT devices are intended to interface between TTL
and NMOS components and standard CMOS devices.
These parts are also plug-in replacements for LS-TTL
devices and can be used to reduce power consumption in
existing designs.
Features
s
TTL input compatible
s
3-STATE outputs for connection to system busses
s
High output drive current: 6 mA (min)
s
High speed: 16 ns typical propagation delay
s
Low power: 80
碌A(chǔ)
(74HCT Series)
Ordering Code:
Order Number
MM74HCT245WM
MM74HCT245SJ
MM74HCT245MTC
MM74HCT245N
Package Number
M20B
M20D
MTC20
N20A
Package Description
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300鈥?Wide
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300鈥?Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter 鈥淴鈥?to the ordering code.
Connection Diagram
Pin Assignments for DIP, SOIC, SOP and TSSOP
Truth Table
Control
Inputs
G
L
L
H
H
=
HIGH Level
L
=
LOW Level
X
=
Irrelevant
Operation
DIR
L
H
X
245
B data to A bus
A data to B bus
isolation
Top View
漏 1999 Fairchild Semiconductor Corporation
DS005366.prf
www.fairchildsemi.com
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