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SN54AHCT574, SN74AHCT574
OCTAL EDGE-TRIGGERED D-TYPE FLIP-FLOPS
WITH 3-STATE OUTPUTS
SCLS245J – OCTOBER 1995 – REVISED JANUARY 2000
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
EPIC
(Enhanced-Performance Implanted
CMOS) Process
Inputs Are TTL-Voltage Compatible
Latch-Up Performance Exceeds 250 mA Per
JESD 17
ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
Package Options Include Plastic
Small-Outline (DW), Shrink Small-Outline
(DB), Thin Very Small-Outline (DGV), Thin
Shrink Small-Outline (PW), and Ceramic
Flat (W) Packages, Ceramic Chip Carriers
(FK), and Standard Plastic (N) and Ceramic
(J) DIPs
description
The ’AHCT574 devices are octal edge-triggered
D-type flip-flops that feature 3-state outputs
designed specifically for driving highly capacitive
or relatively low-impedance loads. These devices
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 logic levels of the data
(D) inputs.
A buffered output-enable (OE) input places the eight outputs in either a normal logic state (high or low) 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 without interface or
pullup components.
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.
To ensure the high-impedance state during power up or power down, OE 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.
The SN54AHCT574 is characterized for operation over the full military temperature range of –55
°
C to 125
°
C.
The SN74AHCT574 is characterized for operation from –40
°
C to 85
°
C.
Copyright
2000, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
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 is a trademark of Texas Instruments Incorporated.
SN54AHCT574 . . . J OR W PACKAGE
SN74AHCT574 . . . DB, DGV, DW, N, OR PW PACKAGE
(TOP VIEW)
SN54AHCT574 . . . FK PACKAGE
(TOP VIEW)
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
GND
V
CC
1Q
2Q
3Q
4Q
5Q
6Q
7Q
8Q
CLK
3
2 1 20 19
9 10 11 12 13
4
5
6
7
8
18
17
16
15
14
2Q
3Q
4Q
5Q
6Q
3D
4D
5D
6D
7D
2
1
O
8
7
1
8
G
C
V
C