Texas Instruments SN74ABT16821DGGR, SN74ABT16821DL, SN74ABT16821DLR Datasheet
SN54ABT16821, SN74ABT16821
20-BIT BUS-INTERFACE FLIP-FLOPS
WITH 3-STATE OUTPUTS
SCBS216B – JUNE 1992 – REVISED JANUARY 1997
D
Members of the Texas Instruments
Widebus
D
State-of-the-Art
Family
EPIC-ΙΙB
BiCMOS Design
Significantly Reduces Power Dissipation
D
ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
D
T ypical V
(Output Ground Bounce) < 1 V
OLP
at VCC = 5 V, TA = 25°C
D
Distributed VCC and GND Pin Configuration
Minimizes High-Speed Switching Noise
D
Flow-Through Architecture Optimizes PCB
Layout
D
High-Drive Outputs (–32-mA IOH,
64-mA I
D
Package Options Include Plastic Thin
OL
)
Shrink Small-Outline (DGG), 300-mil Shrink
Small-Outline (DL) Packages and 380-mil
Fine-Pitch Ceramic Flat (WD) Package
Using 25-mil Center-to-Center Spacings
description
These 20-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, bidirectional bus drivers with
parity, and working registers.
The ’ABT16821 can be used as two 10-bit
flip-flops or one 20-bit flip-flop. The 20 flip-flops
are edge-triggered D-type flip-flops. On the
positive transition of the clock (CLK) input, the
device provides true data at the Q outputs.
SN54ABT16821 . . . WD PACKAGE
SN74ABT16821 . . . DGG OR DL PACKAGE
1OE
1Q1
1Q2
GND
1Q3
1Q4
V
CC
1Q5
1Q6
1Q7
GND
1Q8
1Q9
1Q10
2Q1
2Q2
2Q3
GND
2Q4
2Q5
2Q6
V
CC
2Q7
2Q8
GND
2Q9
2Q10
2OE
(TOP VIEW)
1
56
2
55
3
54
4
53
5
52
6
51
7
50
8
49
9
48
10
47
11
46
12
45
13
44
14
43
15
42
16
41
17
40
18
39
19
38
20
37
21
36
22
35
23
34
24
33
25
32
26
31
27
30
28
29
1CLK
1D1
1D2
GND
1D3
1D4
V
CC
1D5
1D6
1D7
GND
1D8
1D9
1D10
2D1
2D2
2D3
GND
2D4
2D5
2D6
V
CC
2D7
2D8
GND
2D9
2D10
2CLK
A buffered output-enable (OE
) input can be used to place the ten outputs in either a normal logic state (high
or low logic level) 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 need for interface or pullup components.
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.
T o ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup
resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.
The SN54ABT16821 is characterized for operation over the full military temperature range of –55°C to 125°C.
The SN74ABT16821 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.
Widebus and EPIC-ΙΙB 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
Copyright 1997, Texas Instruments Incorporated
1
SN54ABT16821, SN74ABT16821
20-BIT BUS-INTERFACE FLIP-FLOPS
WITH 3-STATE OUTPUTS
SCBS216B – JUNE 1992 – REVISED JANUARY 1997
OE
L ↑ H H
L ↑ LL
L LX Q
H X X Z
FUNCTION TABLE
(each flip-flop)
INPUTS
CLK D
OUTPUT
Q
0
logic symbol
†
1OE
1CLK
2OE
2CLK
1D1
1D2
1D3
1D4
1D5
1D6
1D7
1D8
1D9
1D10
2D1
2D2
2D3
2D4
2D5
2D6
2D7
2D8
2D9
2D10
1
56
28
29
55
54
52
51
49
48
47
45
44
43
42
41
40
38
37
36
34
33
31
30
EN2
EN4
1D
3D
C1
C3
10
12
13
14
15
16
17
19
20
21
23
24
26
27
2
1Q1
3
1Q2
5
1Q3
6
1Q4
8
1Q5
9
1Q6
1Q7
1Q8
1Q9
1Q10
2Q1
2Q2
2Q3
2Q4
2Q5
2Q6
2Q7
2Q8
2Q9
2Q10
2
4
†
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
logic diagram (positive logic)
1
1OE
SN54ABT16821, SN74ABT16821
20-BIT BUS-INTERFACE FLIP-FLOPS
WITH 3-STATE OUTPUTS
SCBS216B – JUNE 1992 – REVISED JANUARY 1997
1CLK
1D1
2OE
2CLK
2D1
56
55
28
29
42
One of Ten
Channels
One of Ten
Channels
C1
1D
To Nine Other Channels
C1
1D
15
2
1Q1
2Q1
To Nine Other Channels
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, VCC –0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, VI (see Note 1) –0.5 V to 7 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage range applied to any output in the high or power-off state, VO –0.5 V to 5.5 V. . . . . . . . . . . . . . . . . . .
Current into any output in the low state, IO: SN54ABT16821 96 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74ABT16821 128 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
Output clamp current
Package thermal impedance, θJA (see Note 2): DGG package 81°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output negative-voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
2. The package thermal impedance is calculated in accordance with EIA/JEDEC Std JESD51.
(V
< 0) –18 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IK
I
(V
, IOK
< 0) –50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
O
DL package 74°C/W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
–65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
stg
†
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
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