CD54HC245 Datasheet, PDF (2/7 Pages) Texas Instruments – High Speed CMOS Logic Octal-Bus Transceiver, Three-State, Non-Inverting

CD54HC245, CD54HCT245, CD74HC245, CD74HCT245
Description
and the HC/HCT643.
The Harris CD54HC245, CD54HCT245, and CD74HC245,
CD74HCT245 are high-speed octal three-state bidirectional
transceivers intended for two-way asynchronous
communication between data buses. They have high drive
current outputs which enable high-speed operation while
driving large bus capacitances. They provide the low power
consumption of standard CMOS circuits with speeds and
drive capabilities comparable to that of LSTTL circuits.
The CD54HC245, CD54HCT245, CD74HC245 and
CD74HCT245 allow data transmission of the B bus or from
the B bus to the A bus. The logic level at the direction input
(DIR) determines the direction. The output enable input
(OE), when high, puts the I/O ports in the high-impedance
state.
The HC/HCT245 is similar in operation to the HC/HCT640
Ordering Information
TEMP.
PART NUMBER RANGE (^oC)
PACKAGE
PKG.
NO.
CD54HC245F
-55 to 125 20 Ld CERDIP F20.3
CD54HCT245F
-55 to 125 20 Ld CERDIP F20.3
CD74HC245E
-55 to 125 20 Ld PDIP
E20.3
CD74HCT245E
-55 to 125 20 Ld PDIP
E20.3
CD74HC245M
-55 to 125 20 Ld SOIC
M20.3
CD74HCT245M
-55 to 125 20 Ld SOIC
M20.3
NOTES:
1. When ordering, use the entire part number. Add the suffix 96 to
obtain the variant in the tape and reel.
2. Wafer or die for this part number is available which meets all elec-
trical specifications. Please contact your local sales office or
Harris customer service for ordering information.
Functional Diagram
2
A0
3
A1
4
A2
5
A3
6
A4
7
A5
8
A6
9
A7
1
DIR
19
OE
18
B0
17
B1
16
B2
15
B3
14
B4
13
B5
12
B6
11
B7
TRUTH TABLE
CONTROL INPUTS
OE
DIR
OPERATION
L
L
B Data to A Bus
L
H
A Data to B Bus
H
X
Isolation
H = High Level, L = Low Level, X = Irrelevant
To prevent excess currents in the High-Z (Isolation) modes all I/O
terminals should be terminated with 10kΩ to 1MΩ resistors.
2