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SCAS267A − MARCH 1993 − REVISED MAY 1995
DGG OR DL PACKAGE
(TOP VIEW)
D Member of the Texas Instruments
Widebus Family
D EPIC (Enhanced-Performance Implanted
D ESD Protection Exceeds 2000 V Per
MIL-STD-883C, Method 3015; Exceeds
200 V Using Machine Model (C = 200 pF,
R = 0)
OE
Q1
Q2
GND
Q3
Q4
1
2
3
4
5
6
7
8
9
10
56 CLK
55 D1
54 D2
53 GND
52 D3
51 D4
CMOS) Submicron Process
D Latch-Up Performance Exceeds 250 mA
V
50
V
CC
CC
Per JEDEC Standard JESD-17
Q5
Q6
Q7
GND 11
Q8 12
49 D5
48 D6
D Bus Hold On Data Inputs Eliminates the
Need for External Pullup/Pulldown
Resistors
47
D7
46 GND
45 D8
D Package Options Include Plastic 300-mil
Shrink Small-Outline (DL) and Thin Shrink
Small-Outline (DGG) Packages
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
Q9
Q10
Q11
Q12
Q13
GND
Q14
Q15
Q16
D9
D10
D11
D12
D13
GND
D14
D15
D16
description
This 20-bit flip-flop is designed specifically for
low-voltage (3.3-V) V operation; it is tested at
CC
2.5-V, 2.7-V, and 3.3-V V
.
CC
The SN74ALVC16721’s 20 flip-flops are edge-
triggered D-type flip-flops with qualified clock
storage. On the positive transition of the clock
(CLK) input, the device provides true data at the
Q outputs if the clock-enable (CLKEN) input is low.
If CLKEN is high, no data is stored.
V
V
CC
CC
Q17
Q18
GND
Q19
Q20
NC
D17
D18
GND
D19
D20
A buffered output-enable (OE) input places the
20 outputs in either a normal logic state (high
or low level) or a high-impedance state. In the
high-impedance state, the outputs neither load
CLKEN
nor drive the bus lines significantly. The high-impedance state and increased drive provide the capability to drive
bus lines without 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.
Active bus-hold circuitry holds unused or floating data inputs at a valid logic level.
The SN74ALVC16721 is available in TI’s shrink small-outline (DL) and thin shrink small-outline (DGG)
packages, which provide twice the I/O pin count and functionality of standard small-outline packages in the
same printed-circuit-board area.
The SN74ALVC16721 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.
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Copyright 1995, Texas Instruments Incorporated
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ꢢ ꢦ ꢣ ꢢꢛ ꢜꢯ ꢞꢝ ꢡ ꢩꢩ ꢧꢡ ꢟ ꢡ ꢠ ꢦ ꢢ ꢦ ꢟ ꢣ ꢌ
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1
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