3-State Bus Driving Inverting Outputs
Buffered Control Inputs
Package Options Include Plastic
Small-Outline (DW), Ceramic Chip Carriers
(FK), and Standard Plastic (N) and Ceramic
(J) 300-mil DIPs

description
These octal D-type edge-triggered flip-flops
feature 3-state outputs designed specifically for
driving highly capacitive or relatively lowimpedance
loads. They are particularly suitable
for implementing buffer registers, I/O ports,
bidirectional bus drivers, and working registers.
On the positive transition of the clock (CLK) input,
the Q outputs are set to the complement of the
logic states set up at the data (D) inputs. The
’ALS534A and SN74AS534 have inverted outputs,
but otherwise are functionally equivalent to
the ’ALS374A and SN74AS374.
A buffered output-enable (OE) input places the
eight outputs in either a normal logic state (high or
low logic levels) or a high-impedance state. In the
high-impedance state, the outputs neither load
nor drive the bus lines significantly. The
high-impedance state and increased drive
provide the capability to drive bus lines without
interface or pullup components.
OE does not affect the internal operations of the flip-flops. Old data can be retained or new data can be entered
while the outputs are off.
The SN54ALS534A is characterized for operation over the full military temperature range of –55°C to 125°C.
The SN74ALS534A and SN74AS534 are characterized for operation from 0°C to 70°C.