November 1994
54F/74F257A
Quad 2-Input Multiplexer with TRI-STATEÉ 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 present the selected data in true (non-inverted) form. The outputs 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
YMultiplexer expansion by tying outputs together
YNon-inverting TRI-STATE outputs
YInput clamp diodes limit high-speed termination effects
YGuaranteed 4000V minimum ESD protection
Commercial |
Military |
Package |
Package Description |
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Number |
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74F257APC |
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N16E |
16-Lead (0.300× Wide) Molded Dual-In-Line |
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54F257ADM (Note 2) |
J16A |
16-Lead Ceramic Dual-In-Line |
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74F257ASC (Note 1) |
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M16A |
16-Lead (0.150× Wide) Molded Small Outline, JEDEC |
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74F257ASJ (Note 1) |
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M16D |
16-Lead (0.300× Wide) Molded Small Outline, EIAJ |
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54F257AFM (Note 2) |
W16A |
16-Lead Cerpack |
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54F257ALL (Note 2) |
E20A |
20-Lead Ceramic Leadless Chip Carrier, Type C |
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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 |
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Pin Assignment |
Pin Assignment |
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for DIP, SOIC and Flatpak |
for LCC |
TL/F/9507 ± 3
IEEE/IEC
TL/F/9507 ± 1
TL/F/9507 ± 2
TL/F/9507 ± 5
TRI-STATEÉ is a registered trademark of National Semiconductor Corporation.
C1995 National Semiconductor Corporation |
TL/F/9507 |
RRD-B30M75/Printed in U. S. A. |
Outputs STATE-TRI with Multiplexer Input-2 Quad 54F/74F257A
Unit Loading/Fan Out
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54F/74F |
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Pin Names |
Description |
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U.L. |
Input IIH/IIL |
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HIGH/LOW |
Output IOH/IOL |
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S |
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Common Data Select Input |
1.0/1.0 |
20 mA/b0.6 mA |
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OE |
TRI-STATE Output Enable Input (Active LOW) |
1.0/1.0 |
20 mA/b0.6 mA |
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I0a ± I0d |
Data Inputs from Source 0 |
1.0/1.0 |
20 mA/b0.6 mA |
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I1a ± I1d |
Data Inputs from Source 1 |
1.0/1.0 |
20 mA/b0.6 mA |
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Za ± Zd |
TRI-STATE Multiplexer Outputs |
150/40 (33.3) |
b3 mA/24 mA (20 mA) |
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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 I0x inputs are selected and when Select is HIGH, the I1x 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 equation for the outputs is shown below:
Zn e OE # (In # S a Ion # 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 impedance state to avoid high currents that would exceed the maximum ratings. Designers should ensure the Output Enable signals to TRI-STATE devices whose outputs are tied together are designed so there is no overlap.
Truth Table
Output |
Select |
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Data |
Output |
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Enable |
Input |
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Inputs |
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OE |
S |
I0 |
I1 |
Z |
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H |
X |
X |
X |
Z |
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L |
H |
X |
L |
L |
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L |
H |
X |
H |
H |
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L |
L |
L |
X |
L |
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L |
L |
H |
X |
H |
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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 |
b65§C to a150§C |
Ambient Temperature under Bias |
b55§C to a125§C |
Junction Temperature under Bias |
b55§C to a175§C |
Plastic |
b55§C to a150§C |
VCC Pin Potential to |
b0.5V to a7.0V |
Ground Pin |
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Input Voltage (Note 2) |
b0.5V to a7.0V |
Input Current (Note 2) |
b30 mA to a5.0 mA |
Voltage Applied to Output |
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in HIGH State (with VCC e 0V) |
b0.5V to VCC |
Standard Output |
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TRI-STATE Output |
b0.5V to a5.5V |
Current Applied to Output |
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in LOW State (Max) |
twice the rated IOL (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 |
b55§C to a125§C |
Military |
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Commercial |
0§C to a70§C |
Supply Voltage |
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Military |
a4.5V to a5.5V |
Commercial |
a4.5V to a5.5V |
DC Electrical Characteristics
Symbol |
Parameter |
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54F/74F |
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Units |
VCC |
Conditions |
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Min |
Typ |
Max |
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VIH |
Input HIGH Voltage |
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2.0 |
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V |
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Recognized as a HIGH Signal |
VIL |
Input LOW Voltage |
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0.8 |
V |
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Recognized as a LOW Signal |
VCD |
Input Clamp Diode Voltage |
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b1.2 |
V |
Min |
IIN e b18 mA |
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VOH |
Output HIGH |
54F |
10% VCC |
2.5 |
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IOH e b1 mA |
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Voltage |
54F |
10% VCC |
2.4 |
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IOH e b3 mA |
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74F |
10% VCC |
2.5 |
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V |
Min |
IOH e b1 mA |
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74F |
10% VCC |
2.4 |
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IOH e b3 mA |
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74F |
5% VCC |
2.7 |
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IOH e b1 mA |
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74F |
5% VCC |
2.7 |
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IOH e b3 mA |
VOL |
Output LOW |
54F |
10% VCC |
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0.5 |
V |
Min |
IOL e 20 mA |
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Voltage |
74F |
10% VCC |
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0.5 |
IOL e 24 mA |
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IIH |
Input HIGH |
54F |
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20.0 |
mA |
Max |
VIN e 2.7V |
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Current |
74F |
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5.0 |
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IBVI |
Input HIGH Current |
54F |
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100 |
mA |
Max |
VIN e 7.0V |
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Breakdown Test |
74F |
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7.0 |
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ICEX |
Output HIGH |
54F |
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250 |
mA |
Max |
VOUT e VCC |
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Leakage Current |
74F |
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50 |
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VID |
Input Leakage |
74F |
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4.75 |
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V |
0.0 |
IID e 1.9 mA |
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Test |
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All Other Pins Grounded |
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IOD |
Output Leakage |
74F |
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3.75 |
mA |
0.0 |
VIOD e 150 mV |
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Circuit Current |
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All Other Pins Grounded |
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IIL |
Input LOW Current |
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b0.6 |
mA |
Max |
VIN e 0.5V |
IOZH |
Output Leakage Current |
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50 |
mA |
Max |
VOUT e 2.7V |
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IOZL |
Output Leakage Current |
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b50 |
mA |
Max |
VOUT e 0.5V |
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IOS |
Output Short-Circuit Current |
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b60 |
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b150 |
mA |
Max |
VOUT e 0V |
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IZZ |
Bus Drainage Test |
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500 |
mA |
0.0V |
VOUT e 5.25V |
ICCH |
Power Supply Current |
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9.0 |
15 |
mA |
Max |
VO e HIGH |
ICCL |
Power Supply Current |
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14.5 |
22 |
mA |
Max |
VO e LOW |
ICCZ |
Power Supply Current |
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15 |
23 |
mA |
Max |
VO e HIGH Z |
3
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