Philips N74ALS257N, N74ALS258DB, N74ALS258N, N74ALS258D, N74ALS257D Datasheet

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74ALS257/74ALS258

Data selector/multiplexer

Product specification
IC05 Data Handbook

1991 Feb 08

INTEGRATED CIRCUITS

Philips Semiconductors Product specification

74ALS257/74ALS258Data selector/multiplexer

74ALS257 Quad 2-input data selector, non-inverting (3-State)
74ALS258 Quad 2-input data selector, inverting (3-State)

2

1991 Feb 08 853–1 130 01670

DESCRIPTION

The 74ALS257 is a quad 2-input multiplexer which selects 4 bits of
data from one of two sources under the control of a common select
input (S). The output enable input (OE

) is active when Low. When

OE

is High, all of the outputs (Yn) are forced to a High impedance

state (3-State) regardless of all other input conditions.
Moving data from two registers to a common output bus is a typical

use of the 74ALS257. The state of the select input determines the
particular register from which data comes.

The device is the logic implementation of 4-pole, 2-position switch
where the position of the switch is determined by the logic levels
supplied to the select input. The 74ALS258 is similar but has
inverting outputs (Y

n).

TYPE

TYPICAL

PROPAGATION DELAY

TYPICAL

SUPPLY CURRENT

(TOTAL)

74ALS257 7.0ns 7mA
74ALS258 7.0ns 7mA

ORDERING INFORMATION

ORDER CODE

DESCRIPTION COMMERCIAL RANGE

V

CC

= 5V ±10%,

T

amb

= 0°C to +70°C

DRAWING

NUMBER

16-pin plastic DIP 74ALS257N, 74ALS258 SOT38-4

16-pin plastic SO 74ALS257D, 74ALS258D SOT109-1

16-pin plastic SSOP

Type II

74ALS257DB, 74ALS258DB SOT338-1

INPUT AND OUTPUT LOADING AND FAN-OUT TABLE

PINS DESCRIPTION

74ALS (U.L.)

HIGH/LOW

LOAD VALUE

HIGH/LOW

Ina, Inb, Inc, Ind Data inputs 1.0/1.0 20µA/0.1mA

S Select input 1.0/1.0 20µA/0.1mA

OE Enable input 1.0/1.0 20µA/0.1mA

Ya – Yd, Ya – Yd Data outputs 20/240 0.4mA/24mA

NOTE: One (1.0) ALS unit load is defined as: 20µA in the High state and 0.1mA in the Low state.

PIN CONFIGURATION – 74ALS257

16
15
14
13
12
11
107

6

5

4

3

2

1

Yb

V

CC

Yd
I0c
I1c

I1d

OE
I0d

S

I0a

I1b

I1a

Ya

I0b

98GND Yc

SF00673

PIN CONFIGURATION – 74ALS258

16
15
14
13
12
11
107

6

5

4

3

2

1

Y

b

V

CC

Yd
I0c
I1c

I1d

OE
I0d

S

I0a

I1b

I1a

Y

a

I0b

98GND Yc

SC00079

Philips Semiconductors Product specification

74ALS257/74ALS258Data selector/multiplexer

1991 Feb 08

3

LOGIC SYMBOL – 74ALS257

VCC = Pin 16
GND = Pin 8

SF00674

1

15

S
OE

2356111014

I0a I1a I0b I1b I0c I1c I0d

Ya Yb Yc Yd

47912

13

I1d

LOGIC SYMBOL – 74ALS258

VCC = Pin 16
GND = Pin 8

SC00080

1

15

S
OE

2356111014

I0a I1a I0b I1b I0c I1c I0d

Ya Yb Yc Yd

47912

13

I1d

IEC/IEEE SYMBOL – 74ALS257

SF00675

2

1

15

EN

1

G1

3

4

1

MUX

5
6

7

10
11

9

13
14

12

IEC/IEEE SYMBOL – 74ALS258

SC00081

2

1

15

EN

1

G1

3

4

1

MUX

5
6

7

10
11

9

13
14

12

LOGIC DIAGRAM – 74ALS257

OE I0a I1a I0b I1b I0c I1c I0d I1d S

152356111014131

Ya Yb Yc Yd

47912

V

CC

= Pin 16

GND = Pin 8

SC00082

LOGIC DIAGRAM – 74ALS258

OE I0a I1a I0b I1b I0c I1c I0d I1d S

152356111014131

Y

aYbYcYd

47912

V

CC

= Pin 16

GND = Pin 8

SC00083

Philips Semiconductors Product specification

74ALS257/74ALS258Data selector/multiplexer

1991 Feb 08

4

FUNCTION T ABLE – 74ALS257

INPUTS OUTPUT

OE S I0n I1n Yn

H X X X Z
L L L X L
L L H X H
L H X L L
L H X H H

H = High voltage level
L = Low voltage level
X = Don’t care
Z = High impedance “off” state

FUNCTION T ABLE – 74ALS258

INPUTS OUTPUT

OE S I0n I1n Yn

H X X X Z
L L L X H
L L H X L
L H X L H
L H X H L

H = High voltage level
L = Low voltage level
X = Don’t care
Z = High impedance “off” state

ABSOLUTE MAXIMUM RATINGS

(Operation beyond the limit set forth in this table may impair the useful life of the device.
Unless otherwise noted these limits are over the operating free air temperature range.)

SYMBOL

PARAMETER RATING UNIT

V

CC

Supply voltage –0.5 to +7.0 V

V

IN

Input voltage –0.5 to +7.0 V

I

IN

Input current –30 to +5 mA

V

OUT

Voltage applied to output in High output state –0.5 to V

CC

V

I

OUT

Current applied to output in Low output state 48 mA

T

amb

Operating free-air temperature range 0 to +70 °C

T

stg

Storage temperature range –65 to +150 °C

RECOMMENDED OPERATING CONDITIONS

LIMITS

SYMBOL

PARAMETER

MIN NOM MAX

UNIT

V

CC

Supply voltage 4.5 5.0 5.5 V

V

IH

High-level input voltage 2.0 V

V

IL

Low-level input voltage 0.8 V

I

IK

Input clamp current –18 mA

I

OH

High-level output current –2.6 mA

I

OL

Low-level output current 24 mA

T

amb

Operating free-air temperature range 0 +70 °C