74AC16823 Datasheet, PDF (1/9 Pages) Texas Instruments – 16-BIT BUS INTERFACE FLIP-FLOPS WITH 3-STATE OUTPUTS

54AC16823, 74AC16823
18ĆBIT BUS INTERFACE FLIPĆFLOPS
WITH 3ĆSTATE OUTPUTS
SCAS243A − APRIL 1991 − REVISED APRIL 1996
D Members of the Texas Instruments
Widebus  Family
D Provides Extra Data Width Necessary for
Wider Address/Data Paths or Buses With
Parity
D Flow-Through Architecture Optimizes
PCB Layout
D Distributed V_CC and GND Pin Configuration
Minimizes High-Speed Switching Noise
D EPIC  (Enhanced-Performance Implanted
CMOS) 1-µm Process
D 500-mA Typical Latch-Up Immunity
at 125°C
D Package Options Include Plastic 300-mil
Shrink Small-Outline (DL) Package Using
25-mil Center-to-Center Pin Spacings and
380-mil Fine-Pitch Ceramic Flat (WD)
Package 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 ’AC16823 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.
54AC16823 . . . WD PACKAGE
74AC16823 . . . DL PACKAGE
(TOP VIEW)
1CLR 1
1OE 2
1Q1 3
GND 4
1Q2 5
1Q3 6
V_CC 7
1Q4 8
1Q5 9
1Q6 10
GND 11
1Q7 12
1Q8 13
1Q9 14
2Q1 15
2Q2 16
2Q3 17
GND 18
2Q4 19
2Q5 20
2Q6 21
V_CC 22
2Q7 23
2Q8 24
GND 25
2Q9 26
2OE 27
2CLR 28
56 1CLK
55 1CLKEN
54 1D1
53 GND
52 1D2
51 1D3
50 V_CC
49 1D4
48 1D5
47 1D6
46 GND
45 1D7
44 1D8
43 1D9
42 2D1
41 2D2
40 2D3
39 GND
38 2D4
37 2D5
36 2D6
35 V_CC
34 2D7
33 2D8
32 GND
31 2D9
30 2CLKEN
29 2CLK
The output enable (OE) input can be used to place the outputs in either a normal logic state (high or low) 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 74AC16823 is packaged in TI’s shrink small-outline package (DL), which provides twice the I/O pin count
and functionality of standard small-outline packages in the same printed-circuit-board area.
The 54AC16374 is characterized for operation over the full military temperature range of −55°C to 125°C. The
74AC16823 is characterized for operation from −40°C to 85°C.
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.
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.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
• POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
Copyright  1996, Texas Instruments Incorporated
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