TL F 9507
54F74F257A
Quad
2-Input
Multiplexer
with
TRI-STATE
Outputs
November 1994
54F 74F257A
Quad 2-Input Multiplexer with TRI-STATE
Outputs
General Description
The 'F257A is a quad 2-input multiplexer with TRI-STATE
outputs Four bits of data from two sources can be selected
using a Common Data Select input The four outputs pres-
ent the selected data in true (non-inverted) form The out-
puts may be switched to a high impedance state with a
HIGH on the common Output Enable (OE) input allowing
the outputs to interface directly with bus-oriented systems
Features
Y
Multiplexer expansion by tying outputs together
Y
Non-inverting TRI-STATE outputs
Y
Input clamp diodes limit high-speed termination effects
Y
Guaranteed 4000V minimum ESD protection
Commercial
Military
Package
Package Description
Number
74F257APC
N16E
16-Lead (0 300 Wide) Molded Dual-In-Line
54F257ADM (Note 2)
J16A
16-Lead Ceramic Dual-In-Line
74F257ASC (Note 1)
M16A
16-Lead (0 150 Wide) Molded Small Outline JEDEC
74F257ASJ (Note 1)
M16D
16-Lead (0 300 Wide) Molded Small Outline EIAJ
54F257AFM (Note 2)
W16A
16-Lead Cerpack
54F257ALL (Note 2)
E20A
20-Lead Ceramic Leadless Chip Carrier Type C
Note 1
Devices also available in 13
reel Use suffix
e
SCX and SJX
Note 2
Military grade device with environmental and burn-in processing Use suffix
e
DMQB FMQB and LMQB
Logic Symbols
Connection Diagrams
TL F 9507 3
IEEE IEC
TL F 9507 5
Pin Assignment
for DIP SOIC and Flatpak
TL F 9507 1
Pin Assignment
for LCC
TL F 9507 2
TRI-STATE
is a registered trademark of National Semiconductor Corporation
C1995 National Semiconductor Corporation
RRD-B30M75 Printed in U S A
Unit Loading Fan Out
54F 74F
Pin Names
Description
U L
Input I
IH
I
IL
HIGH LOW
Output I
OH
I
OL
S
Common Data Select Input
1 0 1 0
20 mA
b
0 6 mA
OE
TRI-STATE Output Enable Input (Active LOW)
1 0 1 0
20 mA
b
0 6 mA
I
0a
I
0d
Data Inputs from Source 0
1 0 1 0
20 mA
b
0 6 mA
I
1a
I
1d
Data Inputs from Source 1
1 0 1 0
20 mA
b
0 6 mA
Z
a
Z
d
TRI-STATE Multiplexer Outputs
150 40 (33 3)
b
3 mA 24 mA (20 mA)
Functional Description
The 'F257A is a quad 2-input multiplexer with TRI-STATE
outputs It selects four bits of data from two sources under
control of a Common Data Select input When the Select
input is LOW the I
0x
inputs are selected and when Select is
HIGH the I
1x
inputs are selected The data on the selected
inputs appears at the outputs in true (non-inverted) form
The device is the logic implementation of a 4-pole 2-posi-
tion switch where the position of the switch is determined by
the logic levels supplied to the Select input The logic equa-
tion for the outputs is shown below
Z
n
e
OE
(I
n
S
a
I
on
S)
When the Output Enable input (OE) is HIGH the outputs are
forced to a high impedance OFF state If the outputs are
tied together all but one device must be in the high imped-
ance state to avoid high currents that would exceed the
maximum ratings Designers should ensure the Output En-
able signals to TRI-STATE devices whose outputs are tied
together are designed so there is no overlap
Truth Table
Output
Select
Data
Output
Enable
Input
Inputs
OE
S
I
0
I
1
Z
H
X
X
X
Z
L
H
X
L
L
L
H
X
H
H
L
L
L
X
L
L
L
H
X
H
H
e
HIGH Voltage Level
L
e
LOW Voltage Level
X
e
Immaterial
Z
e
High Impedance
Logic Diagram
TL F 9507 4
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays
2
Absolute Maximum Ratings
(Note 1)
If Military Aerospace specified devices are required
please contact the National Semiconductor Sales
Office Distributors for availability and specifications
Storage Temperature
b
65 C to
a
150 C
Ambient Temperature under Bias
b
55 C to
a
125 C
Junction Temperature under Bias
b
55 C to
a
175 C
Plastic
b
55 C to
a
150 C
V
CC
Pin Potential to
Ground Pin
b
0 5V to
a
7 0V
Input Voltage (Note 2)
b
0 5V to
a
7 0V
Input Current (Note 2)
b
30 mA to
a
5 0 mA
Voltage Applied to Output
in HIGH State (with V
CC
e
0V)
Standard Output
b
0 5V to V
CC
TRI-STATE Output
b
0 5V to
a
5 5V
Current Applied to Output
in LOW State (Max)
twice the rated I
OL
(mA)
ESD Last Passing Voltage (Min)
4000V
Note 1
Absolute maximum ratings are values beyond which the device may
be damaged or have its useful life impaired Functional operation under
these conditions is not implied
Note 2
Either voltage limit or current limit is sufficient to protect inputs
Recommended Operating
Conditions
Free Air Ambient Temperature
Military
b
55 C to
a
125 C
Commercial
0 C to
a
70 C
Supply Voltage
Military
a
4 5V to
a
5 5V
Commercial
a
4 5V to
a
5 5V
DC Electrical Characteristics
Symbol
Parameter
54F 74F
Units
V
CC
Conditions
Min
Typ
Max
V
IH
Input HIGH Voltage
2 0
V
Recognized as a HIGH Signal
V
IL
Input LOW Voltage
0 8
V
Recognized as a LOW Signal
V
CD
Input Clamp Diode Voltage
b
1 2
V
Min
I
IN
e b
18 mA
V
OH
Output HIGH
54F 10% V
CC
2 5
I
OH
e b
1 mA
Voltage
54F 10% V
CC
2 4
I
OH
e b
3 mA
74F 10% V
CC
2 5
V
Min
I
OH
e b
1 mA
74F 10% V
CC
2 4
I
OH
e b
3 mA
74F 5% V
CC
2 7
I
OH
e b
1 mA
74F 5% V
CC
2 7
I
OH
e b
3 mA
V
OL
Output LOW
54F 10% V
CC
0 5
V
Min
I
OL
e
20 mA
Voltage
74F 10% V
CC
0 5
I
OL
e
24 mA
I
IH
Input HIGH
54F
20 0
m
A
Max
V
IN
e
2 7V
Current
74F
5 0
I
BVI
Input HIGH Current
54F
100
m
A
Max
V
IN
e
7 0V
Breakdown Test
74F
7 0
I
CEX
Output HIGH
54F
250
m
A
Max
V
OUT
e
V
CC
Leakage Current
74F
50
V
ID
Input Leakage
74F
4 75
V
0 0
I
ID
e
1 9 mA
Test
All Other Pins Grounded
I
OD
Output Leakage
74F
3 75
m
A
0 0
V
IOD
e
150 mV
Circuit Current
All Other Pins Grounded
I
IL
Input LOW Current
b
0 6
mA
Max
V
IN
e
0 5V
I
OZH
Output Leakage Current
50
m
A
Max
V
OUT
e
2 7V
I
OZL
Output Leakage Current
b
50
m
A
Max
V
OUT
e
0 5V
I
OS
Output Short-Circuit Current
b
60
b
150
mA
Max
V
OUT
e
0V
I
ZZ
Bus Drainage Test
500
m
A
0 0V
V
OUT
e
5 25V
I
CCH
Power Supply Current
9 0
15
mA
Max
V
O
e
HIGH
I
CCL
Power Supply Current
14 5
22
mA
Max
V
O
e
LOW
I
CCZ
Power Supply Current
15
23
mA
Max
V
O
e
HIGH Z
3
AC Electrical Characteristics
74F
54F
74F
T
A
e a
25 C
T
A
V
CC
e
Mil
T
A
V
CC
e
Com
Symbol
Parameter
V
CC
e a
5 0V
C
L
e
50 pF
C
L
e
50 pF
Units
C
L
e
50 pF
Min
Typ
Max
Min
Max
Min
Max
t
PLH
Propagation Delay
2 5
4 5
5 5
2 0
7 0
2 0
6 0
ns
t
PHL
I
n
to Z
n
2 0
4 2
5 5
1 5
7 0
2 0
6 0
t
PLH
Propagation Delay
4 0
5 0
9 5
3 5
11 5
3 5
10 5
ns
t
PHL
S to Z
n
2 5
6 5
7 0
2 5
9 0
2 5
8 0
t
PZH
Output Enable Time
2 0
5 9
6 0
2 0
8 0
2 0
7 0
t
PZL
2 5
5 5
7 0
2 5
9 0
2 5
8 0
ns
t
PHZ
Output Disable Time
2 0
4 3
6 0
2 0
7 0
2 0
7 0
t
PLZ
2 0
4 5
6 0
2 0
8 5
2 0
7 0
4
Ordering Information
The device number is used to form part of a simplified purchasing code where the package type and temperature range are
defined as follows
74F
257A
S
C
X
Temperature Range Family
Special Variations
74F
e
Commercial
X
e
Devices shipped in 13 reels
54F
e
Military
QB
e
Military grade with
environmental and burn-in
Device Type
processing shipped in tubes
Package Code
Temperature Range
P
e
Plastic DIP
C
e
Commercial (0 C to
a
70 C)
D
e
Ceramic DIP
M
e
Military (
b
55 C to
a
125 C)
F
e
Flatpak
L
e
Leadless Ceramic Chip Carrier (LCC)
S
e
Small Outline SOIC JEDEC
SJ
e
Small Outline SOIC EIAJ
Physical Dimensions
inches (millimeters)
20-Lead Ceramic Leadless Chip Carrier (L)
NS Package Number E20A
5
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