Datasheet
1
Data sheet acquired from Harris Semiconductor
SCHS168D
Features
• Typical Propagation Delay (A to B, B to A) of 7ns at
V
CC
= 5V, C
L
= 15pF, T
A
= 25
o
C
• Three-State Outputs
• Buffered Inputs
• Fanout (Over Temperature Range)
- Standard Outputs. . . . . . . . . . . . . . . 10 LSTTL Loads
- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
• Wide Operating Temperature Range . . . -55
o
C to 125
o
C
• Balanced Propagation Delay and Transition Times
• Significant Power Reduction Compared to LSTTL
Logic ICs
• HC Types
- 2V to 6V Operation
- High Noise Immunity: N
IL
= 30%, N
IH
= 30% of V
CC
at V
CC
= 5V
• HCT Types
- 4.5V to 5.5V Operation
- Direct LSTTL Input Logic Compatibility,
V
IL
= 0.8V (Max), V
IH
= 2V (Min)
- CMOS Input Compatibility, I
l
≤ 1µA at V
OL
, V
OH
Pinout
CD54HC243, CD54HCT243
(CERDIP)
CD74HC243, CD74HCT243
(PDIP, SOIC)
TOP VIEW
Description
The ’HC243 and ’HCT243 silicon-gate CMOS three-state
bidirectional noninverting buffers are intended for two-way
asynchronous communication between data buses. They
have high-drive-current outputs that enable high-speed oper-
ation when driving large bus capacitances. These circuits
possess the low power dissipation of CMOS circuits and
have speeds comparable to low-power Schottky TTL circuits.
They can drive 15 LSTTL loads.
The states of the output-enable (
OEB, OEA) inputs
determine both the direction of flow (A to B, B to A), and the
three-state mode.
OEB
NC
A0
A1
A2
A3
GND
V
CC
OEA
NC
B0
B1
B2
B3
1
2
3
4
5
6
7
14
13
12
11
10
9
8
Ordering Information
PART NUMBER
TEMP. RANGE
(
o
C) PACKAGE
CD54HC243F3A -55 to 125 14 Ld CERDIP
CD54HCT243F3A -55 to 125 14 Ld CERDIP
CD74HC243E -55 to 125 14 Ld PDIP
CD74HC243M -55 to 125 14 Ld SOIC
CD74HC243MT -55 to 125 14 Ld SOIC
CD74HC243M96 -55 to 125 14 Ld SOIC
CD74HCT243E -55 to 125 14 Ld PDIP
CD74HCT243M -55 to 125 14 Ld SOIC
NOTE: When ordering, use the entire part number. The suffix 96
denotes tape and reel. The suffix T denotes a small-quantity reel of
250.
November 1997 - Revised October 2003
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
Copyright
© 2003, Texas Instruments Incorporated
CD54HC243, CD74HC243,
CD54HCT243, CD74HCT243
High-Speed CMOS Logic
Quad-Bus Transceiver with Three-State Outputs
[
/Title
(
CD74
H
CT24
2
,
C
D74
H
C243
,
C
D74
H
CT24
3
)
/
Sub-
j
ect
(
High
S
peed
C
MOS
L
ogic
Q
uad-