54AC253
54ACT253
Dual 4-Input Multiplexer with TRI-STATE
Outputs
General Description
The 'AC/'ACT253 is a dual 4-input multiplexer with
TRI-STATE outputs. It can select two bits of data from four
sources using common select inputs. The outputs may be in-
dividually switched to a high impedance state with a HIGH
on the respective Output Enable (OE) inputs, allowing the
outputs to interface directly with bus oriented systems.
Features
n
I
CC
and I
OZ
reduced by 50%
n
Multifunction capability
n
Noninverting TRI-STATE outputs
n
Outputs source/sink 24 mA
n
'ACT253 has TTL-compatible inputs
n
Standard Military Drawing (SMD)
-- 'AC253: 5962-87693
-- 'ACT253: 5962-87761
Logic Diagrams
Pin Names
Description
I
0a
I
3a
Side A Data Inputs
I
0b
I
3b
Side B Data Inputs
S
0
, S
1
Common Select Inputs
OE
a
Side A Output Enable Input
OE
b
Side B Output Enable Input
Z
a
, Z
b
TRI-STATE Outputs
TRI-STATE
is a registered trademark of National Semiconductor Corporation.
FACT
is a registered trademark of Fairchild Semiconductor Corporation.
DS100285-1
IEEE/IEC
DS100285-2
August 1998
54AC253
54ACT253
Dual
4-Input
Multiplexer
with
TRI-ST
A
T
E
Outputs
1998 National Semiconductor Corporation
DS100285
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Connection Diagrams
Functional Description
The 'AC/'ACT253 contains two identical 4-input multiplexers
with TRI-STATE outputs. They select two bits from four
sources selected by common Select inputs (S
0
, S
1
). The
4-input multiplexers have individual Output Enable (OE
a
,
OE
b
) inputs which, when HIGH, force the outputs to a high
impedance (High Z) state. This device is the logic implemen-
tation of a 2-pole, 4-position switch, where the position of the
switch is determined by the logic levels supplied to the two
select inputs. The logic equations for the outputs are shown:
Z
a
= OE
a
(I
0a
S
1
S
0
+ I
1a
S
1
S
0
+
I
2a
S
1
S
0
+ I
3a
S
1
S
0
)
Z
b
= OE
b
(I
0b
S
1
S
0
+ I
1b
S
1
S
0
+
I
2b
S
1
S
0
+ I
3b
S
1
S
0
)
If the outputs of TRI-STATE devices are tied together, all but
one device must be in the high impedance state to avoid
high currents that would exceed the maximum ratings. De-
signers should ensure that Output Enable signals to
TRI-STATE devices whose outputs are tied together are de-
signed so that there is no overlap.
Truth Table
Select
Data Inputs
Output
Outputs
Inputs
Enable
S
0
S
1
I
0
I
1
I
2
I
3
OE
Z
X
X
X
X
X
X
H
Z
L
L
L
X
X
X
L
L
L
L
H
X
X
X
L
H
H
L
X
L
X
X
L
L
H
L
X
H
X
X
L
H
L
H
X
X
L
X
L
L
L
H
X
X
H
X
L
H
H
H
X
X
X
L
L
L
H
H
X
X
X
H
L
H
Address Inputs S
0
and S
1
are common to both sections.
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance
Pin Assignment
for DIP and Flatpak
DS100285-3
Pin Assignment
for LCC
DS100285-4
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2
Logic Diagram
DS100285-5
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
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3
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
CC
)
-0.5V to +7.0V
DC Input Diode Current (I
IK
)
V
I
= -0.5V
-20 mA
V
I
= V
CC
+ 0.5V
+20 mA
DC Input Voltage (V
I
)
-0.5V to V
CC
+ 0.5V
DC Output Diode Current (I
OK
)
V
O
= -0.5V
-20 mA
V
O
= V
CC
+ 0.5V
+20 mA
DC Output Voltage (V
O
)
-0.5V to V
CC
+ 0.5V
DC Output Source
or Sink Current (I
O
)
50 mA
DC V
CC
or Ground Current
per Output Pin (I
CC
or I
GND
)
50 mA
Storage Temperature (T
STG
)
-65C to +150C
Junction Temperature (T
J
)
CDIP
175C
Recommended Operating
Conditions
Supply Voltage (V
CC
)
'AC
2.0V to 6.0V
'ACT
4.5V to 5.5V
Input Voltage (V
I
)
0V to V
CC
Output Voltage (V
O
)
0V to V
CC
Operating Temperature (T
A
)
54AC/ACT
-55C to +125C
Minimum Input Edge Rate (
V/
t)
'AC Devices
V
IN
from 30% to 70% of V
CC
V
CC
@
3.3V, 4.5V, 5.5V
125 mV/ns
Minimum Input Edge Rate (
V/
t)
'ACT Devices
V
IN
from 0.8V to 2.0V
V
CC
@
4.5V, 5.5V
125 mV/ns
Note 1: Absolute maximum ratings are those values beyond which damage
to the device may occur. The databook specifications should be met, without
exception, to ensure that the system design is reliable over its power supply,
temperature, and output/input loading variables. National does not recom-
mend operation of FACT
circuits outside databook specifications.
DC Characteristics for 'AC Family Devices
54AC
Symbol
Parameter
V
CC
T
A
=
Units
Conditions
(V)
-55C to +125C
Guaranteed Limits
V
IH
Minimum High Level
3.0
2.1
V
OUT
= 0.1V
Input Voltage
4.5
3.15
V
or V
CC
- 0.1V
5.5
3.85
V
IL
Maximum Low Level
3.0
0.9
V
OUT
= 0.1V
Input Voltage
4.5
1.35
V
or V
CC
- 0.1V
5.5
1.65
V
OH
Minimum High Level
3.0
2.9
I
OUT
= -50 A
Output Voltage
4.5
4.4
V
5.5
5.4
(Note 2)
V
IN
= V
IL
or V
IH
3.0
2.4
I
OH
= -12 mA
4.5
3.7
V
I
OH
= -24 mA
5.5
4.7
I
OH
= -24 mA
V
OL
Maximum Low Level
3.0
0.1
I
OUT
= 50 A
Output Voltage
4.5
0.1
V
5.5
0.1
(Note 2)
V
IN
= V
IL
or V
IH
3.0
0.50
I
OL
= 12 mA
4.5
0.50
V
I
OL
= 24 mA
5.5
0.50
I
OL
= 24 mA
I
IN
Maximum Input
5.5
1.0
A
V
I
= V
CC
, GND
Leakage Current
I
OZ
Maximum TRI-STATE
V
I
(OE) = V
IL
, V
IH
Current
5.5
5.0
A
V
I
= V
CC
, GND
V
O
= V
CC
, GND
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4
DC Characteristics for 'AC Family Devices
(Continued)
54AC
Symbol
Parameter
V
CC
T
A
=
Units
Conditions
(V)
-55C to +125C
Guaranteed Limits
(Note 3)
I
OLD
Minimum Dynamic
5.5
50
mA
V
OLD
= 1.65V Max
I
OHD
Output Current
5.5
-50
mA
V
OHD
= 3.85V Min
I
CC
Maximum Quiescent
5.5
80.0
A
V
IN
= V
CC
Supply Current
or GND
Note 2: All outputs loaded; thresholds on input associated with output under test.
Note 3: Maximum test duration 2.0 ms, one output loaded at a time.
Note 4: I
IN
and I
CC
@
3.0V are guaranteed to be less than or equal to the respective limit
@
5.5V V
CC
.
I
CC
for 54AC
@
25C is identical to 74AC
@
25C.
DC Characteristics for 'ACT Family Devices
54ACT
Symbol
Parameter
V
CC
T
A
=
Units
Conditions
(V)
-55C to +125C
Guaranteed Limits
V
IH
Minimum High Level
4.5
2.0
V
V
OUT
= 0.1V
Input Voltage
5.5
2.0
or V
CC
- 0.1V
V
IL
Maximum Low Level
4.5
0.8
V
V
OUT
= 0.1V
Input Voltage
5.5
0.8
or V
CC
- 0.1V
V
OH
Minimum High Level
4.5
4.4
V
I
OUT
= -50 A
Output Voltage
5.5
5.4
(Note 5)
V
IN
= V
IL
or V
IH
4.5
3.70
V
I
OH
= -24 mA
5.5
4.70
I
OH
= -24 mA
V
OL
Maximum Low Level
4.5
0.1
V
I
OUT
= 50 A
Output Voltage
5.5
0.1
(Note 5)
V
IN
= V
IL
or V
IH
4.5
0.50
V
I
OL
= 24 mA
5.5
0.50
I
OL
= 24 mA
I
IN
Maximum Input
5.5
1.0
A
V
I
= V
CC
, GND
Leakage Current
I
OZ
Maximum TRI-STATE
5.5
5.0
A
V
I
= V
IL
, V
IH
Current
V
O
= V
CC
, GND
I
CCT
Maximum
5.5
1.6
mA
V
I
= V
CC
- 2.1V
I
CC
/Input
(Note 6)
I
OLD
Minimum Dynamic
5.5
50
mA
V
OLD
= 1.65V Max
I
OHD
Output Current
5.5
-50
mA
V
OHD
= 3.85V Min
I
CC
Maximum Quiescent
5.5
80.0
A
V
IN
= V
CC
Supply Current
or GND
Note 5: All outputs loaded; thresholds on input associated with output under test.
Note 6: Maximum test duration 2.0 ms, one output loaded at a time.
Note 7: I
CC
for 54ACT
@
25C is identical to 74ACT
@
25C.
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