SN54ACT574, SN74ACT574
OCTAL D-TYPE EDGE-TRIGGERED FLIP-FLOPS
WITH 3-STATE OUTPUTS
SCAS537C – OCTOBER 1995 – REVISED JANUARY 2000
SN54ACT574 . . . J OR W PACKAGE
SN74ACT574 . . . DB, DW, N, OR PW PACKAGE
(TOP VIEW)
Inputs Are TTL-Voltage Compatible
EPIC (Enhanced-Performance Implanted
CMOS) 1-µm Process
Package Options Include Plastic
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
OE
1D
2D
3D
4D
5D
6D
7D
8D
V
CC
Small-Outline (DW), Shrink Small-Outline
(DB), and Thin Shrink Small-Outline (PW)
Packages, Ceramic Chip Carriers (FK) and
Flatpacks (W), and Standard Plastic (N) and
Ceramic (J) DIPs
1Q
2Q
3Q
4Q
5Q
6Q
7Q
8Q
CLK
description
These 8-bit flip-flops feature 3-state outputs
designed specifically for driving highly capacitive
or relatively low-impedance loads. The devices
are particularly suitable for implementing buffer
registers, I/O ports, bidirectional bus drivers, and
working registers.
GND
SN54ACT574 . . . FK PACKAGE
(TOP VIEW)
The eight flip-flops of the ’ACT574 devices are
D-type edge-triggered flip-flops. On the positive
transition of the clock (CLK) input, the Q outputs
are set to the logic levels set up at the data (D)
inputs.
3
2
1
20 19
18
4
5
6
7
8
3D
4D
5D
6D
7D
2Q
3Q
4Q
5Q
6Q
17
16
15
14
A buffered output-enable (OE) input can be used
to place the eight outputs in either a normal logic
state (high or low logic levels) or the
high-impedance state. In the high-impedance
state, the outputs neither load nor drive the bus
lines significantly. The high-impedance state and
the increased drive provide the capability to drive
bus lines in a bus-organized system without need
for interface or pullup components.
9 10 11 12 13
OE does not affect internal operations of the flip-flop. Old data can be retained or new data can be entered while
the outputs are in the high-impedance state.
The SN54ACT574 is characterized for operation over the full military temperature range of –55°C to 125°C. The
SN74ACT574 is characterized for operation from –40°C to 85°C.
FUNCTION TABLE
(each flip-flop)
INPUTS
OUTPUT
Q
OE
L
CLK
D
H
L
↑
↑
H
L
L
L
H or L
X
X
X
Q
0
H
Z
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 is a trademark of Texas Instruments Incorporated.
Copyright 2000, Texas Instruments Incorporated
UNLESS OTHERWISE NOTED this document contains PRODUCTION
DATA information 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.
1
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