SN54BCT543, SN74BCT543
OCTAL REGISTERED TRANSCEIVERS
WITH 3ĆSTATE OUTPUTS
SCBS026C − NOVEMBER 1988 − REVISED APRIL 1994
•
•
•
•
SN54BCT543 . . . JT OR W PACKAGE
SN74BCT543 . . . DW OR NT PACKAGE
(TOP VIEW)
State-of-the-Art BiCMOS Design
Significantly Reduces ICCZ
3-State True Outputs
Back-to-Back Registers for Storage
ESD Protection Exceeds 2000 V
Per MIL-STD-883C, Method 3015
Package Options Include Plastic
Small-Outline Packages (DW), Ceramic
Chip Carriers (FK) and Flatpacks (W), and
Plastic and Ceramic 300-mil DIPs (JT, NT)
LEBA
OEBA
A1
A2
A3
A4
A5
A6
A7
A8
CEAB
GND
description
The ′BCT543 octal transceiver contains two sets
of D-type latches for temporary storage of data
flowing in either direction. Separate latch-enable
(LEAB or LEBA) and output-enable (OEAB or
OEBA) inputs are provided for each register to
permit independent control in either direction of
data flow.
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
VCC
CEBA
B1
B2
B3
B4
B5
B6
B7
B8
LEAB
OEAB
A1
OEBA
LEBA
NC
VCC
SN54BCT543 . . . FK PACKAGE
(TOP VIEW)
The A-to-B enable (CEAB) input must be low in
order to enter data from A or to output data from
B. If CEAB is low and LEAB is low, the A-to-B
latches are transparent; a subsequent low-to-high
transition of LEAB puts the A latches in the storage
mode. With CEAB and OEAB both low, the 3-state
B outputs are active and reflect the data present
at the output of the A latches. Data flow from B to
A is similar but requires using the CEBA, LEBA,
and OEBA inputs.
5
A2
A3
A4
NC
A5
A6
A7
3 2 1 28 27 26
25
4
6
24
7
23
8
22
9
21
10
20
11
19
12 13 14 15 16 17 18
B2
B3
B4
NC
B5
B6
B7
A8
CEAB
GND
NC
OEAB
LEAB
B8
The SN54BCT543 is characterized for operation
over the full military temperature range of − 55°C
to 125°C. The SN74BCT543 is characterized for
operation from 0°C to 70°C.
CEBA
B1
•
NC − No internal connection
FUNCTION TABLE†
INPUTS
OEAB
A
OUTPUT
B
X
X
X
Z
X
H
X
Z
L
H
L
X
L
L
L
L
B0‡
L
L
L
L
H
CEAB
LEAB
H
X
H
† A-to-B data flow is shown; B-to-A flow control is the
same except that it uses CEBA, LEBA, and OEBA.
‡ Output level before the indicated steady-state input
conditions were established.
Copyright 1994, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
• DALLAS, TEXAS 75265
• HOUSTON, TEXAS 77251−1443
POST OFFICE BOX 655303
POST OFFICE BOX 1443
2−1
