ST 74VHC157 User Manual

74VHC157

QUAD 2 CHANNEL MULTIPLEXER

■ HIGH SPEED: t

■ LOW POWER DISSIPATION:

I

= 4 µA (MAX.) at TA=25°C

CC

■ HIGH NOISE IMMUNITY:

V

= V

NIH

■ POWER DOWN PROTECTION ON INPUTS

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

OH

■ BALANCED PROPAGATION DELAYS:

t

PLH

■ OPERATING VOLTAGE RANGE:

V

CC

■ PIN AND FUNCTION COMPATIBLE WITH

NIL

| = IOL = 8 mA (MIN)

≅ t

PHL

(OPR) = 2V to 5.5V

= 4.1 ns (TYP.) at VCC = 5V

PD

= 28% VCC (MIN.)

74 SERIES 157

■ IMPROVED LATCH-UP IMMUNITY

■ LOW NOISE: V

= 0.8V (MAX.)

OLP

DESCRIPTION

The 74VHC157 is an advanced high-speed
CMOS QUAD 2-CHANNEL MULTIPLEXER
fabricated with sub-micron silicon gate and
double-layer metal wiring C

2

MOS technology.
It consists of fo ur 2-input digital multiplexer with
common select and strobe inputs. It is a
non-inverting multiplexer. When the STROBE

TSSOPSOP

Table 1: Order Codes

PACKAGE T & R

SOP 74VHC157MTR

TSSOP 74VHC157TTR

input is held high selection of data is inhibited and
all the outputs become low. The SELECT
decoding determines whether the A or B inputs
get routed to their corresponding Y outputs.
Power down protection is provided on all inputs
and 0 to 7V can be accepted on inputs with no
regard to the supply voltage. This device can be
used to interface 5V t o 3V. All inputs and outputs
are equipped with protection circuits against static
discharge, giving them 2KV ESD immunity and
transient excess voltage.

Figure 1: Pin Connection And IEC Logic Symbols

Rev. 4

1/12November 2004

74VHC157

Figure 2: Input Equivalent Circuit Table 2: Pin Description

PIN N° SYMBOL NAME AND FUNCTION

1 SELECT Common Data Select

Inputs

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

A

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

B

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

15 STROBE Strobe Input

8 GND Ground (0V)

Positive Supply Voltage

Table 3: Truth Table

16 V

INPUTS OUTPUT

CC

STROBE

HXXXL

LLLXL
LLHXH
LHXLL
LHXHH

X : Don’t ca re

Figure 3: Logic Diagram

SELECT A B Y

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74VHC157

Table 4: Absolute Maximum Ratings

Symbol Parameter Value Unit

V

V

V

I

I

OK

I

or I

I

CC

T

T

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied

Table 5: Recommended Operating Conditions

Symbol Parameter Value Unit

V

V
V
T

dt/dv

Supply Voltage

CC

DC Input Voltage

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

Storage Temperature

stg

Lead Temperature (10 sec)

L

Supply Voltage

CC

Input Voltage

I

Output Voltage 0 to V

O

Operating Temperature

op

Input Rise and Fall Time (note 1) (V
(V

= 3.3 ± 0.3V)

CC

= 5.0 ± 0.5V)

CC

-0.5 to +7.0 V

-0.5 to +7.0 V

- 20 mA

± 20 mA
± 25 mA
± 50 mA

-65 to +150 °C
300 °C

2 to 5.5 V
0 to 5.5 V

CC

-55 to 125 °C
0 to 100

0 to 20

ns/V

V

V

1) VIN from 30 % t o 70% of V

CC

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74VHC157

Table 6: DC Specifications

Symbol Parameter

V

V

V

High Level Input

IH

Voltage

V

Low Level Input

IL

Voltage

High Level Output

OH

Voltage

Low Level Output

OL

Voltage

Input Leakage

I

I

Current
Quiescent Supply

I

CC

Current

V

3.0 to

3.0 to

0 to

Test Condition Value

= 25°C

(V)

CC

T

A

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

-40 to 85°C -55 to 125°C

2.0 1.5 1.5 1.5

5.5

0.7V

CC

0.7V

CC

0.7V

CC

2.0 0.5 0.5 0.5

5.5

2.0

3.0

4.5

3.0

4.5

2.0

3.0

4.5

3.0

4.5

5.5

5.5

=-50 µA

I

O

=-50 µA

I

O

=-50 µA

I

O

I

=-4 mA

O

=-8 mA

I

O

=50 µA

I

O

=50 µA

I

O

I

=50 µA

O

=4 mA

I

O

=8 mA

I

O

V

= 5.5V or GND

I

= VCC or GND

V

I

0.3V

CC

1.9 2.0 1.9 1.9

2.9 3.0 2.9 2.9

4.4 4.5 4.4 4.4

2.58 2.48 2.4

3.94 3.8 3.7

0.0 0.1 0.1 0.1

0.0 0.1 0.1 0.1

0.0 0.1 0.1 0.1

0.36 0.44 0.55

0.36 0.44 0.55

± 0.1 ± 1 ± 1 µA

44040µA

0.3V

CC

0.3V

CC

Unit

V

V

V

V

Table 7: AC Electrical Characteristics (Input t

Test Condition Value

Symbol Parameter

t

Propagation Delay

PLH

t

t
t

t
t

(*) Voltage range is 3.3V ± 0.3V
(**) Voltage range is 5.0V ±

Time

PHL

A, B to Y

Propagation Delay

PLH

Time

PHL

SELECT to Y

Propagation Delay

PLH

Time STROBE

PHL

0.5V

to Y

V

3.3

3.3

5.0

5.0

3.3

3.3

5.0

5.0

3.3

3.3

5.0

5.0

C

CC

(V)

L

(pF)

(*)

15 6.2 9.7 1.0 11.5 1.0 11.5

(*)

50 8.7 13.2 1.0 15.0 1.0 15.0

(**)

15 4.1 6.4 1.0 7.5 1.0 7.5

(**)

50 5.6 8.4 1.0 9.5 1.0 9.5

(*)

15 8.4 13.2 1.0 15.5 1.0 15.5

(*)

50 10.9 16.7 1.0 19.0 1.0 19.0

(**)

15 5.3 8.1 1.0 9.5 1.0 9.5

(**)

50 6.8 10.1 1.0 11.5 1.0 11.5

(*)

15 8.7 13.6 1.0 16.0 1.0 16.0

(*)

50 11.2 17.1 1.0 19.5 1.0 19.5

(**)

15 5.6 8.6 1.0 10.0 1.0 10.0

(**)

50 7.1 10.6 1.0 12.0 1.0 12.0

= tf = 3ns)

r

= 25°C

T

A

-40 to 85°C -55 to 125°C

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

Unit

ns

ns

ns

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