• Local Bus-Latch Capability
• Noninverting Logic
• Package Options Include Plastic
Small-Outline Packages, Ceramic Chip
Carriers, and Standard Plastic and Ceramic
These octal bus transceivers are designed for
asynchronous communication between data
buses. The control function implementation allows
for maximum flexibility in timing.
These devices allow data transmission from the A
bus to the B bus or from the B bus to the A bus
depending upon 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 in all)
will remain at their last states.
The SN54F621 is characterized for operation over
the full military temperature range of – 55°C to
125°C. The SN74F621 is characterized for
operation from 0°C to 70°C.
OCTAL BUS TRANSCEIVERS
WITH OPEN-COLLECTOR OUTPUTS
SDFS004B – D2932, MARCH 1987 – REVISED OCTOBER 1993
SN54F621 . . . J PACKAGE
SN74F621 . . . DW OR N PACKAGE
SN54F621 . . . FK PACKAGE
3 2 1 20 19
9 10 11 12 13
L L B data to A bus
B data to A bus,
A data to B bus
H H A data to B bus
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.
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Copyright © 1993, Texas Instruments Incorporated