NSC 5962R8968801VFA, 5962R8968801VEA, 5962R8968801V2A, 5962R8968801FA, 5962R8968801EA Datasheet

54AC157•54ACT157
Quad 2-Input Multiplexer

General Description

The ’AC/’ACT157 is a high-speed quad 2-input multiplexer.
Four bitsof data from two sources can be selected using the
common Selectand Enable inputs. The four outputs present
the selected data in the true (noninverted) form. The ’AC/
’ACT157 can also be used as a function generator.

Features

n ICCand IOZreduced by 50

%

n Outputs source/sink 24 mA
n ’ACT157 has TTL-compatible inputs
n Standard Microcircuit Drawing (SMD)

—’AC157: 5962-89539
—’ACT157: 5962-89688

Logic Symbols

Pin Names Description

I

0a–I0d

Source 0 Data Inputs

I

1a–I1d

Source 1 Data Inputs

E

Enable Input
S Select Input
Z

a–Zd

Outputs

Connection Diagrams

FACT™is a trademark of Fairchild Semiconductor Corporation.

DS100272-1

IEEE/IEC

DS100272-2

Pin Assignment

for DIP and Flatpak

DS100272-3

Pin Assignment

for LCC

DS100272-4

July 1998

54AC157

•

54ACT157 Quad 2-Input Multiplexer

© 1998 NationalSemiconductor Corporation DS100272 www.national.com

Functional Description

The ’AC/’ACT157 is a quad 2-input multiplexer. It selects
four bits ofdata fromtwo sources underthe control of a com­mon Select input (S). The Enable input (E) is active-LOW.
When E is HIGH, all of the outputs (Z) are forced LOW re­gardless of all other inputs. The ’AC/’ACT157 is the logic
implementation of a4-pole, 2-positionswitch where the posi­tion of theswitch is determinedby thelogic levels suppliedto
the Select input. The logic equations for the outputs are
shown below:

Z

a

=

E

•

(I

1a

•

S+I

0a

•

S)

Z

b

=

E

•

(I

1b

•

S+I

0b

•

S)

Z

c

=

E

•

(I

1c

•

S+I

0c

•

S)

Z

d

=

E

•

(I

1d

•

S+I

0d

•

S)

Acommon use ofthe ’AC/ACT157is the movingof data from
two groups of registers to four common output busses. The
particular register from which the data comes is determined
by the state of the Select input. A less obvious use is as a
function generator. The ’AC/’ACT157 can generate any four

of the sixteen different functions of two variables with one
variable common. This is useful for implementing gating
functions.

Truth Table

Inputs Outputs

E

SI

0

I

1

Z

HX X X L
LH X L L
LH X H H
LL L X L
LLH X H

H

=

HIGH Voltage Level
L=LOW Voltage Level
X=Immaterial

Logic Diagram

DS100272-5

Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.

www.national.com 2

Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National SemiconductorSales 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 VCC+ 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 VCC+ 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

) −65˚C to +150˚C

Junction Temperature (T

J

)

CDIP 175˚C

Recommended Operating
Conditions

Supply Voltage (VCC)

’AC 2.0V to 6.0V
’ACT 4.5V to 5.5V

Input Voltage (V

I

) 0VtoV

CC

Output Voltage (VO) 0VtoV

CC

Operating Temperature (TA)

54AC/ACT −55˚C to +125˚C

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 ratingsare those values beyond which damage
to the devicemay occur. The databookspecifications should be met, without
exception, to ensurethat the systemdesign is reliableover its powersupply,
temperature, and output/input loading variables. National does not recom­mend operation of FACT

™

circuits outside databook specifications.

DC Characteristics for ’AC Family Devices

54AC

Symbol Parameter V

CC

T

A

=

Units Conditions

(V) −55˚C to +125˚C

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 µA

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 µA

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 µA V

I

=

V

CC

, GND

Leakage Current

I

OLD

Minimum Dynamic
Output Current (Note 3)

5.5 50 mA V

OLD

=

1.65V Max

I

OHD

5.5 −50 mA V

OHD

=

3.85V Min

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