Datasheet 74LCX257TTR, 74LCX257MTR, 74LCX257M Datasheet (SGS Thomson Microelectronics)

1/10June 2002

■ 5V TOLERANT INPUTS AND OUTPUTS

■ HIGH SPEED :

t

PD

= 6.0 ns (MAX.) at VCC = 3V

■ POWER DOWN PROTECTION ON INPUT S

AND OUTPUTS

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

OH

| = IOL = 24mA (MIN) at VCC = 3V

■ PCI BUS LEVELS GUARANT EED AT 2 4 mA

■ BALANCED PROPAGATION DELAYS:

t

PLH

≅ t

PHL

■ OPERATING VOLTAGE RANGE:

V

CC

(OPR) = 2.0V to 3.6V (1.5V Data

Retention)

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 257

■ LATCH-UP PERFORMANCE EXCEEDS

500mA (JESD 17)

■ ESD PERFORMANCE:

HBM > 2000V (MIL STD 883 method 3015);
MM > 200V

DESCRIPTION

The 74LCX257 is a low v oltage CMOS QUAD 2
CHANNEL MULTIPLEXER (3-STATE) fabricated
with sub-micron silicon gate and double-layer
metal wiring C

2

MOS technology. It is ideal for low
power and high speed 3.3V applications; it can be
interfaced to 5V signal environment for both inputs
and ou tputs.

It is composed of four independent 2 channel
multiplexers with commo n SELECT and ENABLE
(OE

) INPUT. The 74LCX257 is a non-inverting
multiplexer. When the ENABLE INPUT is held
"High", all outputs become in high impedance
state. If SELECT INPUT is held "L ow", "A" dat a is
selected, when SELECT INPUT is "High", "B"
data is chosen.
It has same speed performance at 3. 3V than 5V
AC/ACT family, combined with a lower power
consumption.
All inputs and outputs are equipped with
protection circuits against stat ic discharge, giving
them 2KV ESD immunity and transient excess
voltage.

74LCX257

LOW VOLTAGE CMOS QUAD 2 CHANNEL MULTIPLEXER

WITH 5V TOLERANT IN PU TS AN D OU TPUTS (3-STATE)

PIN CONNECTION AND IEC LOGIC SYMBOLS

ORDER CODES

PACKAGE TUBE T & R

SOP 74LCX257M 74LCX257MTR

TSSOP 74LCX257TTR

TSSOPSOP

74LCX257

2/10

INPUT AND OUTPUT EQUIVALENT CIRCUIT

PIN DESCRIPTION

TRUTH TABLE

X : Don’t Care
Z : High Impedance

PIN No 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 3 State Multiplexer Outputs

15 OE

3 State Output Enable Inputs (Active
LOW)

8 GND Ground (0V)

16 V

CC

Positive Supply Voltage

INPUTS OUTPUT

OE

SELECT A B Y

HXXXZ

LLLXL
LLHXH
LHXLL
LHXHH

74LCX257

3/10

LOGIC DIAGRAM

This log i c diagram has not be used to esti m ate propaga tion delays

ABSOLUTE MAXIMUM RATINGS

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

1) I

O

absolute ma xim um rating mu st be observed

2) V

O

< GND

Symbol Parameter Value Unit

V

CC

Supply Voltage

-0.5 to +7.0 V

V

I

DC Input Voltage

-0.5 to +7.0 V

V

O

DC Output Voltage (OFF State)

-0.5 to +7.0 V

V

O

DC Output Voltage (High or Low State) (note 1) -0.5 to VCC + 0.5

V

I

IK

DC Input Diode Current

- 50 mA

I

OK

DC Output Diode Current (note 2)

- 50 mA

I

O

DC Output Current

±

50 mA

I

CC

DC Supply Current per Supply Pin

±

100 mA

I

GND

DC Ground Current per Supply Pin

±

100 mA

T

stg

Storage Temperature

-65 to +150 °C

T

L

Lead Temperature (10 sec)

300 °C

74LCX257

4/10

RECOMMENDED OPERATING CONDITIONS

1) Truth T abl e guaranteed: 1.5V to 3.6V

2) V

IN

from 0.8V to 2V at VCC = 3.0V

DC SPECIFICATIONS

Symbol Parameter Value Unit

V

CC

Supply Voltage (note 1)

2.0 to 3.6 V

V

I

Input Voltage

0 to 5.5 V

V

O

Output Voltage (OFF State)

0 to 5.5 V

V

O

Output Voltage (High or Low State) 0 to V

CC

V

I

OH

, I

OL

High or Low Level Output Current (VCC = 3.0 to 3.6V)

±

24 mA

I

OH

, I

OL

High or Low Level Output Current (VCC = 2.7V)

±

12 mA

T

op

Operating Temperature

-55 to 125 °C

dt/dv Input Rise and Fall Time (note 2) 0 to 10 ns/V

Symbol Parameter

Test Condition Value

Unit

V

CC

(V)

-40 to 85 °C -55 to 125 °C

Min. Max. Min. Max.

V

IH

High Level Input
Voltage

2.7 to 3.6

2.0 2.0 V

V

IL

Low Level Input
Voltage

0.8 0.8 V

V

OH

High Level Output
Voltage

2.7 to 3.6

IO=-100 µAVCC-0.2 VCC-0.2

V

2.7

I

O

=-12 mA

2.2 2.2

3.0

I

O

=-18 mA

2.4 2.4

I

O

=-24 mA

2.2 2.2

V

OL

Low Level Output
Voltage

2.7 to 3.6

I

O

=100 µA

0.2 0.2
V

2.7

I

O

=12 mA

0.4 0.4

3.0

I

O

=16 mA

0.4 0.4

I

O

=24 mA

0.55 0.55

I

I

Input Leakage
Current

2.7 to 3.6

V

I

= 0 to 5.5V

±

5

±

5

µ

A

I

off

Power Off Leakage
Current

0

V

I

or VO = 5.5V

10 10

µ

A

I

OZ

High Impedance
Output Leakage
Current

2.7 to 3.6

V

I

= VIH or V

IL

VO = 0 to V

CC

±

5

±

5

µ

A

I

CC

Quiescent Supply
Current

2.7 to 3.6

VI = VCC or GND

10 10

µ

A

V

I

or VO= 3.6 to 5.5V

±

10

±

10

∆

I

CC

ICC incr. per Input

2.7 to 3.6

VIH = VCC - 0.6V

500 500

µ

A

74LCX257

5/10

DYNAMIC SWITCHING CHARACTERISTICS

1) Number of outputs d ef i ned as "n". Me asured with "n-1" output s switching from HIGH to LO W or LOW to HIGH. The remaini ng outpu t is
measur ed i n the LOW state.

AC ELECTRICAL CHARACTERISTICS

1) Skew is defined as the absolute value of the difference between the actual propagation delay for any two outputs of the same device switch­ing in the same direction, either HIGH or LOW (t

OSLH

= | t

PLHm

- t

PLHn

|, t

OSHL

= | t

PHLm

- t

PHLn

|)

2) Param eter guaran te ed by design

CAPACITIVE CHARACTERISTICS

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

load. (R ef er to Test Circui t). Averag e operating cu rrent can be obtained by the foll owing equat io n. I

CC(opr)

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

channel)

Symbol Parameter

Test Condition Value

Unit

V

CC

(V)

T

A

= 25 °C

Min. Typ. Max.

V

OLP

Dynamic Low Level Quiet
Output (note 1)

3.3

C

L

= 50pF

V

IL

= 0V, VIH = 3.3V

0.8
V

V

OLV

-0.8

Symbol Parameter

Test Condition Value

Unit

V

CC

(V)

C

L

(pF)

R

L

(Ω)

t

s

= t

r

(ns)

-40 to 85 °C -55 to 125 °C

Min. Max. Min. Max.

t

PLH tPHL

Propagation Delay
Time (A, B to Y)

2.7
50 500 2.5

1.5 6.5 1.5 6.5
ns

3.0 to 3.6 1.5 6.0 1.5 6.0

t

PLH tPHL

Propagation Delay
Time (SELECT to Y)

2.7
50 500 2.5

1.5 8.5 1.5 8.5
ns

3.0 to 3.6 1.5 7.0 1.5 7.0

t

PZL tPZH

Output EnableTime 2.7

50 500 2.5

1.5 8.5 1.5 8.5
ns

3.0 to 3.6 1.5 7.0 1.5 7.0

t

PLZ tPHZ

Output DisableTime 2.7

50 500 2.5

1.5 6.0 1.5 6.0
ns

3.0 to 3.6 1.5 5.5 1.5 5.5

t

OSLH

t

OSHL

Output To Output
Skew Time (note1,

2)

3.0 to 3.6 50 500 2.5 1.0 1.0 ns

Symbol Parameter

Test Condition Value

Unit

V

CC

(V)

T

A

= 25 °C

Min. Typ. Max.

C

IN

Input Capacitance

3.3

VIN = 0 to V

CC

7pF

C

OUT

Output Capacitance

3.3

VIN = 0 to V

CC

8pF

C

PD

Power Dissipation Capacitance
(note 1)

3.3 fIN = 10MHz
V

IN

= 0 or V

CC

25

pF

74LCX257

6/10

TEST CIRCUIT

CL = 50 pF or equival ent (includes jig and probe capacitance)
R

L

= R1 = 500Ω or equivalent

R

T

= Z

OUT

of pulse generator (typically 50Ω)

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

TEST SWITCH

t

PLH

, t

PHL

Open

t

PZL

, t

PLZ

6V

t

PZH

, t

PHZ

GND

74LCX257

7/10

WAVEFORM 2 : OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50 % duty cycl e )

74LCX257

8/10

DIM.

mm. inch

MIN. TYP MAX. MIN. TYP. MAX.

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.)

SO-16 MECHANICAL DATA

PO13H

74LCX257

9/10

DIM.

mm. inch

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

TSSOP16 MECHANICAL DATA

c

E

b

A2

A

E1

D

1

PIN 1 IDENTIFICATION

A1

L

K

e

0080338D

74LCX257

10/10

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