Datasheet M74HCT157 Datasheet (ST)

M74HCT157

QUAD 2 CHANNEL MULTIPLEXER

■ HIGH SPEED:

t

= 16ns (TYP.) at VCC = 4.5V

PD

■ LOW POWER DISSIPATION:

I

= 4µA(MAX.) at TA=25°C

CC

■ COMPA TIBLE WITH TTL OUTPUTS :

V

= 2V (MIN.) VIL = 0.8V (MAX)

IH

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 4mA (MIN)

OH

■ BALANCED PROPAGATION DELAYS:

t

≅ t

PHL

PLH

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 157

DESCRIPTION

The M74HCT157 is an high s peed CM OS QUA D
2 CHANNEL MULTIPLEXER fabricated with
silicon gate C

2

MOS technology.
This device consists of four 2-input digital
multiplexer with common select and strobe inputs.
When the STROBE

(ST) input is held high,
selection of data is inhibited and all the outputs
become low. The SELECT decodi ng determines

TSSOPDIP SOP

ORDER CODES

PACKAGE TUBE T & R

DIP M74HCT157B1R

SOP M74HCT157M1R M74HCT157RM13TR

TSSOP M74HCT157TTR

whether the A or B inputs get routed to their
corresponding Y outputs.
All inputs are equipped with protection circuits
against static discharge and transient excess
voltage.

PIN CONNECTION AND IEC LOGIC SYMBOLS

1/9September 2001

M74HCT157

INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION

PIN No SYMBOL NAME AND FUNCTION

1 SELECT Common Data Select

2, 5, 11, 14 1A to 4A Data Inputs From

3, 6, 10, 13 1B to 4B Data Inputs From

4, 7, 9, 12 1Y to 4Y Multiplexer Output

15 STROBE

8 GND Ground (0V)

16 V

TRUTH TABLE

INPUTS OUTPUTS

CC

Input

Source A

Source B

Strobe Inputs

Positive Supply Voltage

STROBE

HXXXL

LLLXL
LLHXH
LHXLL
LHXHH

X : Don’t Care

LOGIC DIAGRAM

SELECT A B Y

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M74HCT157

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

V

V

I

I

OK

I

I

or I

CC

P

T

T

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
(*) 500mW at 65

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter Value Unit

V

V

V
T
t

r

Supply Voltage

CC

DC Input Voltage -0.5 to VCC + 0.5

I

DC Output Voltage -0.5 to VCC + 0.5

O

DC Input Diode Current

IK

DC Output Diode Current
DC Output Current

O

DC VCC or Ground Current

GND

Power Dissipation

D

Storage Temperature

stg

Lead Temperature (10 sec)

L

°C; derate to 300mW by 10mW/°C from 65° C to 85°C

Supply Voltage

CC

Input Voltage 0 to V

I

Output Voltage 0 to V

O

Operating Temperature

op

, t

Input Rise and Fall Time (VCC = 4.5 to 5.5V)

f

-0.5 to +7 V

± 20 mA
± 20 mA
± 25 mA
± 50 mA

500(*) mW

-65 to +150 °C

300 °C

4.5 to 5.5 V

CC
CC

-55 to 125 °C
0 to 500 ns

V
V

V
V

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M74HCT157

DC SPECIFICATIONS

Symbol Parameter

V

V

V

V

I

∆ I

* : Applicable only to DIR, G, G input

High Level Input

IH

Voltage

Low Level Input

IL

Voltage

High Level Output

OH

Voltage
Low Level Output

OL

Voltage

I

Input Leakage

I

Current
Quiescent Supply

CC

Current
Additional Worst

CC

Case Supply
Current

Test Condition Value

T

= 25°C

V

CC

(V)

A

Min. Typ. Max. Min. Max. Min. Max.

4.5
to

2.0 2.0 2.0 V

5.5

4.5
to

0.8 0.8 0.8 V

5.5

4.5

4.5

5.5

5.5

IO=-20 µA

I

=-4.0 mA

O

IO=20 µA

I

=4.0 mA

O

= VCC or GND

V

I

= VCC or GND

V

I

5.5 Per Input pin

V

= 0.5V or

I

V

= 2.4V

I

4.4 4.5 4.4 4.4

4.18 4.31 4.13 4.10

0.0 0.1 0.1 0.1

0.17 0.26 0.33 0.40
± 0.1 ± 1 ± 1 µA

2.0 2.9 3.0 mA

Other Inputs at

V

or GND

CC

I

= 0

O

-40 to 85°C -55 to 125°C

Unit

V

V

44080µA

AC ELECTRICAL CHARACTERISTICS (CL = 50 pF, Input tr = tf = 6ns)

Test Condition Value

= 25°C

Symbol Parameter

t

TLH tTHL

t

PLH tPHL

t

PLH tPHL

t

PLH tPHL

Output Transition
Time

Propagation Delay
Time (A, B - Y)

Propagation Delay
Time (SELECT - Y)

Propagation Delay
Time (STROBE

V

CC

(V)

4.5 8151922ns

4.5 16 25 31 38 ns

4.5 19 30 38 45 ns

4.5 17 27 34 41 ns

-Y)

T

A

Min. Typ. Max. Min. Max. Min. Max.

-40 to 85°C -55 to 125°C

Unit

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M74HCT157

CAPACITIVE CHARACTERISTICS

Test Condition Value

T

Symbol Parameter

V

CC

(V)

C

C

1) CPD is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without

load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
nel)

Input Capacitance

IN

Power Dissipation

PD

Capacitance (note 1)5.0 50 pF

5.0 5101010pF

= 25°C

A

Min. Typ. Max. Min. Max. Min. Max.

TEST CIRCUIT

-40 to 85°C -55 to 125°C

= CPD x VCC x fIN + ICC/4(per chan-

CC(opr)

Unit

CL = 50pF or equivalent (in cl udes jig and probe capac i tance)

= Z

R

of pulse generator (typically 50Ω)

T

OUT

WAVEFORM : PROPAGATION DELAY TIMES (f=1MHz; 50% duty cycle)

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M74HCT157

Plastic DIP-16 (0.25) MECHANICAL DATA

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

a1 0.51 0.020

B 0.77 1.65 0.030 0.065
b 0.5 0.020

b1 0.25 0.010

D 20 0.787
E 8.5 0.335

e 2.54 0.100

e3 17.78 0.700

F 7.1 0.280

I 5.1 0.201

L 3.3 0.130

Z 1.27 0.050

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P001C

SO-16 MECHANICAL DATA

M74HCT157

DIM.

A 1.75 0.068
a1 0.1 0.2 0.003 0.007
a2 1.65 0.064

b 0.35 0.46 0.013 0.018

b1 0.19 0.25 0.007 0.010

C 0.5 0.019
c1 45° (typ.)

D 9.8 10 0.385 0.393

E 5.8 6.2 0.228 0.244

e 1.27 0.050

e3 8.89 0.350

F 3.8 4.0 0.149 0.157

G 4.6 5.3 0.181 0.208

L 0.5 1.27 0.019 0.050

M 0.62 0.024

S8° (max.)

MIN. TYP MAX. MIN. TYP. MAX.

mm. inch

PO13H

7/9

M74HCT157

TSSOP16 MECHANICAL DATA

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

A 1.2 0.047

A1 0.05 0.15 0.002 0.004 0.006

A2 0.8 1 1.05 0.031 0.039 0.041

b 0.19 0.30 0.007 0.012

c 0.09 0.20 0.004 0.0089

D 4.9 5 5.1 0.193 0.197 0.201

E 6.2 6.4 6.6 0.244 0.252 0.260

E1 4.3 4.4 4.48 0.169 0.173 0.176

e 0.65 BSC 0.0256 BSC

K0° 8°0° 8°

L 0.45 0.60 0.75 0.018 0.024 0.030

A2

A

A1

b

e

c

K

L

E

D

E1

PIN 1 IDENTIFICATION

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1

0080338D

M74HCT157

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