54ACT16841 Datasheet, PDF (1/6 Pages) Texas Instruments – 20-BIT BUS-INTERFACE D-TYPE LATCHES WITH 3-STATE OUTPUTS

54ACT16841, 74ACT16841
20-BIT BUS-INTERFACE D-TYPE LATCHES
WITH 3-STATE OUTPUTS
SCAS174A – MAY 1991 – REVISED APRIL 1996
D Members of the Texas Instruments
Widebus ™ Family
D Inputs Are TTL-Voltage Compatible
D 3-State Outputs Drive Bus Lines Directly
D Provide Extra Bus Driving/Latches
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 Thin
Shrink Small-Outline (DGG) Packages,
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 20-bit latches feature 3-state outputs
designed specifically for driving highly capacitive
or relatively low-impedance loads. They are
particularly suitable for implementing buffer
registers, I/O ports, bidirectional bus drivers, and
working registers.
54ACT16841 . . . WD PACKAGE
74ACT16841 . . . DGG OR DL PACKAGE
(TOP VIEW)
1OE 1
1Q1 2
1Q2 3
GND 4
1Q3 5
1Q4 6
V_CC 7
1Q5 8
1Q6 9
1Q7 10
GND 11
1Q8 12
1Q9 13
1Q10 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
2Q10 27
2OE 28
56 1LE
55 1D1
54 1D2
53 GND
52 1D3
51 1D4
50 V_CC
49 1D5
48 1D6
47 1D7
46 GND
45 1D8
44 1D9
43 1D10
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 2D10
29 2LE
The ’ACT16841 can be used as two 10-bit latches
or one 20-bit latch. The 20 latches are transparent
D-type. While the latch-enable (1LE or 2LE) input
is high, the Q outputs of the corresponding 10-bit
latch follow the data (D) inputs. When LE is taken
low, the Q outputs are latched at the levels that
were set up at the D inputs.
A buffered output-enable (1OE or 2OE) input can be used to place the outputs of the corresponding 10-bit latch
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 latches. Old data can be retained or new data can be entered
while the outputs are in the high-impedance state.
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.
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Copyright © 1996, Texas Instruments Incorporated
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