54ACT16823, 74ACT16823
18-BIT BUS-INTERFACE FLIP-FLOPS
WITH 3-STATE OUTPUTS

SCAS160A – APRIL 1991 – REVISED APRIL 1996
1POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
C0068 Members of the Texas Instruments
Widebus Family
C0068 Inputs Are TTL-Voltage Compatible
C0068 Provide Extra Data Width Necessary for
Wider Address/Data Paths or Buses With
Parity
C0068 Flow-Through Architecture Optimizes PCB
Layout
C0068 Distributed V
CC
and GND Pin Configuration
Minimizes High-Speed Switching Noise
C0068 EPIC (Enhanced-Performance Implanted
CMOS) 1-µm Process
C0068 Package Options Include Plastic 300-mil
Shrink Small-Outline (DL) Packages Using
25-mil Center-to-Center Pin Spacings and
380-mil Fine-Pitch Ceramic Flat (WD)
Packages Using 25-mil Center-to-Center
Pin Spacings

description
These 18-bit flip-flops feature 3-state outputs
designed specifically for driving highly-capacitive
or relatively low-impedance loads. They are
particularly suitable for implementing wider buffer
registers, I/O ports, parity bus interfacing, and
working registers.
The ’ACT16823 can be used as two 9-bit flip-flops
or one 18-bit flip-flop. With the clock-enable
(CLKEN) input low, the D-type flip-flops enter data
on the low-to-high transitions of the clock. Taking
CLKEN high disables the clock buffer, thus
latching the outputs. Taking the clear (CLR) input
low causes the Q outputs to go low independently
of the clock.
A buffered output-enable (OE) input can be used to place the 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.
OE does not affect the internal operation of the flip-flops. Old data can be retained or new data can be entered
while the outputs are in the high-impedance state.
The 74ACT16823 is packaged in theTI shrink small-outline package, which provides twice the I/O pin count and
functionality of standard small-outline packages in the same printed-circuit-board area.
The 54ACT16823 is characterized for operation over the full military temperature range of 55°C to 125°C. The
74ACT16823 is characterized for operation from –40°C to 85°C
Copyright  1996, 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.

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 and Widebus are trademarks of Texas Instruments Incorporated.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
1CLR
1OE
1Q1
GND
1Q2
1Q3
V
CC
1Q4
1Q5
1Q6
GND
1Q7
1Q8
1Q9
2Q1
2Q2
2Q3
GND
2Q4
2Q5
2Q6
V
CC
2Q7
2Q8
GND
2Q9
2OE
2CLR
1CLK
1CLKEN
1D1
GND
1D2
1D3
V
CC
1D4
1D5
1D6
GND
1D7
1D8
1D9
2D1
2D2
2D3
GND
2D4
2D5
2D6
V
CC
2D7
2D8
GND
2D9
2CLKEN
2CLK
54ACT16823 . . . WD PACKAGE
74ACT16823 . . . DL PACKAGE
(TOP VIEW)