SN54ABT623A, SN74ABT623
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS

SCBS114D – FEBRUARY 1991 – REVISED MAY 1997
1POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
C0068 State-of-the-Art EPIC-II B BiCMOS Design
Significantly Reduces Power Dissipation
C0068 ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
C0068 Latch-Up Performance Exceeds 500 mA Per
JEDEC Standard JESD-17
C0068 Typical V
OLP
(Output Ground Bounce) < 1 V
at V
CC
= 5 V, T
A
= 25°C
C0068 High-Drive Outputs (–32-mA I
OH
, 64-mA I
OL
)
C0068 Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages, Ceramic Chip Carriers (FK),
Ceramic Flat (W) Package, and Plastic (N)
and Ceramic (JT) DIPs
description
The SN54ABT623A and SN74ABT623 bus
transceivers are designed for asynchronous
communication between data buses. The
control-function implementation allows for
maximum flexibility in timing. The SN54ABT623A
and SN74ABT623 provide true data at their
outputs.
These devices allow data transmission from the
A bus to the B bus or from the B bus to the A bus,
depending on the logic levels at the output-enable
(OEAB and OEBA) inputs.
The output-enable inputs can be used to disable the device so that the buses are effectively isolated. The
dual-enable configuration gives the transceivers the capability of storing data by simultaneously enabling OEAB
and OEBA. Each output reinforces its input in this configuration. When both OEAB and OEBA are enabled and
all other data sources to the two sets of bus lines are at high impedance, both sets of bus lines (16 total) remain
at their last states.
To ensure the high-impedance state during power up or power down, OEBA should be tied to V
CC
through a
pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.
OEAB should be tied to GND through a pulldown resistor; the minimum value of the resistor is determined by
the current-sourcing capability of the driver.
The SN54ABT623A is characterized for operation over the full military temperature range of –55°C to 125°C.
The SN74ABT623 is characterized for operation from –40°C to 85°C.
Copyright  1997, 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.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
EPIC-II B is a trademark of Texas Instruments Incorporated.
SN54ABT623A . . . JT OR W PACKAGE
SN74ABT623 . . . DB, DW, N, OR PW PACKAGE
(TOP VIEW)
SN54ABT623A . . . FK PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
OEAB
A1
A2
A3
A4
A5
A6
A7
A8
GND
V
CC
OEBA
B1
B2
B3
B4
B5
B6
B7
B8
3212019
910111213
4
5
6
7
8
18
17
16
15
14
B1
B2
B3
B4
B5
A3
A4
A5
A6
A7
A2 A1 OEAB
B7 B6
V OEBA
A8
GND
B8
CC