ꢀꢁꢂ ꢃ ꢄꢅ ꢀ ꢆꢇ ꢈ ꢃ ꢉ ꢊꢋ ꢀꢁꢌ ꢃ ꢄꢅ ꢀ ꢆ ꢇ ꢈ ꢃ ꢉ ꢊꢋ ꢀꢁꢌ ꢃ ꢄꢅ ꢀꢆ ꢇꢈꢃ ꢃ
ꢇ ꢍ ꢎꢏ ꢐ ꢋꢎ ꢑꢀ ꢋ ꢏ ꢁꢐ ꢒꢓꢔꢄꢕꢒ ꢋꢖꢍ ꢐ ꢗꢘ ꢒꢋ ꢅꢄꢐ ꢕꢙꢒꢀ ꢋꢚ ꢏꢐ ꢙꢋ ꢉ ꢍ ꢀꢐꢄꢐ ꢒꢋ ꢛ ꢑꢐ ꢘꢑ ꢐꢀ
SDAS151A − D2910 — JUNE 1988 — REVISED JANUARY 1990
• 3-State Buffer-Type Outputs Drive Bus
SN54ALS29843 . . . JT Package
SN74ALS29843 . . . DW or NT Package
Lines Directly
(Top View)
• Bus-Structured Pinout
• Provide Extra Bus Driving Latches
OC
1D
2D
3D
4D
5D
6D
7D
8D
V
CC
1
24
23
22
21
20
19
18
17
16
15
14
13
Necessary For Wider Address/Data Paths
or Buses With Parity
1Q
2Q
3Q
4Q
5Q
6Q
7Q
8Q
9Q
PRE
C
2
3
• Buffered Control Inputs to Reduce DC
4
Loading
5
6
• Power-Up High-Impedance
7
• Package Options Include Plastic “Small
Outline” Packages and Standard Plastic
and Ceramic 300-Mil DIPs
8
9
9D
CLR
GND
10
11
12
description
These 9-bit latches feature three-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.
SN74ALS29844 . . . DW or NT Package
(Top View)
The nine latches are transparent D-type. The
′ALS29843 has noninverting data (D) inputs. The
′ALS29844 has inverting D inputs.
OC
1D
2D
3D
4D
5D
6D
7D
8D
V
1
24
23
22
21
20
19
18
17
16
15
14
13
CC
1Q
2Q
3Q
4Q
5Q
6Q
7Q
8Q
9Q
PRE
C
2
3
A buffered output control (OC) input can be used
to place the nine outputs in either a normal logic
state (high or low levels) or a high-impedance
state. The outputs are also in the high-impedance
state during power-up and power-down
conditions. The outputs remain in the
high-impedance state while the device is
powered-down. 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 the
bus lines in a bus-organized system without need
for interface or pullup components.
4
5
6
7
8
9
9D
CLR
GND
10
11
12
The output control (OC) does not affect the internal operation of the latches. Old data can be retained or new
data can be entered while the outputs are off.
The SN54ALS29843 is characterized for operation over the full military range of − 55°C to 125°C. The
SN74ALS29843 and SN74ALS29844 are characterized for operation from 0°C to 70°C.
ꢘꢓ ꢛ ꢖꢑ ꢕ ꢐꢏ ꢛ ꢁ ꢖ ꢄꢐꢄ ꢜꢝ ꢞ ꢟꢠ ꢡꢢ ꢣꢜꢟ ꢝ ꢜꢤ ꢥꢦ ꢠ ꢠ ꢧꢝꢣ ꢢꢤ
ꢟꢞ ꢨꢦ ꢩꢪ ꢜꢥ ꢢ ꢣ ꢜ ꢟꢝ ꢫꢢ ꢣ ꢧ ꢬ ꢘꢠ ꢟ ꢫꢦꢥ ꢣꢤ ꢥꢟ ꢝꢞꢟꢠ ꢡ ꢣꢟ
Copyright 1990, Texas Instruments Incorporated
ꢤ ꢨꢧ ꢥ ꢜ ꢞꢜ ꢥ ꢢ ꢣ ꢜꢟ ꢝꢤ ꢨꢧ ꢠ ꢣ ꢭꢧ ꢣꢧ ꢠ ꢡꢤ ꢟꢞ ꢐꢧꢮ ꢢꢤ
ꢏꢝ ꢤ ꢣꢠ ꢦ ꢡ ꢧ ꢝꢣ ꢤ ꢤ ꢣ ꢢ ꢝꢫ ꢢ ꢠꢫ ꢯ ꢢꢠ ꢠ ꢢ ꢝꢣꢰꢬ ꢘꢠ ꢟꢫꢦ ꢥꢣ ꢜꢟꢝ
ꢨꢠ ꢟ ꢥ ꢧ ꢤ ꢤ ꢜꢝ ꢱ ꢫꢟ ꢧ ꢤ ꢝꢟ ꢣ ꢝꢧ ꢥꢧ ꢤꢤ ꢢꢠ ꢜꢪ ꢰ ꢜꢝꢥ ꢪꢦꢫ ꢧ
ꢣ ꢧ ꢤ ꢣꢜ ꢝꢱ ꢟꢞ ꢢ ꢪꢪ ꢨꢢ ꢠ ꢢ ꢡ ꢧ ꢣ ꢧ ꢠ ꢤ ꢬ
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