3-State Buffer-Type Outputs Drive Bus
Lines Directly
Bus-Structured Pinout
Package Options Include Plastic
Small-Outline (DW) Packages, Ceramic
Chip Carriers (FK), and Plastic (NT) and
Ceramic (JT) DIPs

description
These dual 4-bit D-type latches feature 3-state
outputs designed specifically for bus driving.
These devices are particularly suitable for
implementing buffer registers, I/O ports,
bidirectional bus drivers, and working registers.
The dual 4-bit latches are transparent D-type
latches. While the latch-enable (LE) input is high,
the Q outputs follow the data (D) inputs in true
form, according to the function table. When LE is
low, the outputs are latched. When the clear (CLR)
input goes low, the Q outputs go low
independently of LE. The outputs are in the
high-impedance state when the output-enable
(OE) input is at a high logic level.
The SN54ALS873B and SN54AS873A are
characterized for operation over the full military
temperature range of −55°C to 125°C. The
SN74ALS873B and SN74AS873A are
characterized for operation from 0°C to 70°C.