Philips N74ALS157D, N74ALS158D, N74ALS158N Datasheet

INTEGRATED CIRCUITS

74ALS157/74ALS158 Data selector/multiplexer

Product specification	1991 Feb 08
IC05 Data Handbook

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Philips Semiconductors	Product specification
Data selector/multiplexer	74ALS157/74ALS158

74ALS157 Quad 2-input data selector/multiplexer, non-inverting 74ALS158 Quad 2-input data selector/multiplexer, inverting

DESCRIPTION

The 74ALS157 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 enable input (E) is active when Low. When E is High, all of the outputs (Yn) are forced Low regardless of all other input conditions.

Moving data from two registers to a common output bus is a typical use of the 74ALS157. 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 74ALS158 is similar but has inverting outputs (Yn).

		TYPICAL	TYPICAL
	TYPE		SUPPLY CURRENT
		PROPAGATION DELAY
			(TOTAL)
	74ALS157	6.0ns	6mA
	74ALS158	6.0ns	6mA

ORDERING INFORMATION

		ORDER CODE
			DRAWING
	DESCRIPTION	COMMERCIAL RANGE
			NUMBER
		VCC = 5V ±10%,
		Tamb = 0°C to +70°C
	16-pin plastic DIP	74ALS157N, 74ALS158N	SOT38-4
	16-pin plastic SO	74ALS157D, 74ALS158D	SOT109-1

INPUT AND OUTPUT LOADING AND FAN-OUT TABLE

PINS

DESCRIPTION

74ALS (U.L.)

LOAD VALUE

HIGH/LOW

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

Enable input

1.0/1.0

20μA/0.1mA

E

Ya ± Yd,

Data outputs

20/240

0.4mA/24mA

Ya ± Yd

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

PIN CONFIGURATION ± 74ALS157

PIN CONFIGURATION ± 74ALS158

S

S

1

16

VCC

1

16

VCC

I0a

I0a

2

15

E

2

15

E

I1a

I0d

I1a

I0d

3

14

3

14

Ya

I1d

I1d

4

13

Ya

4

13

I0b

Yd

I0b

5

12

5

12

Yd

I1b

I0c

I1b

I0c

6

11

6

11

Yb

I1c

I1c

7

10

Yb

7

10

GND

Yc

GND

8

9

8

9

Yc

SC00051

SC00052

LOGIC SYMBOL ± 74ALS157

LOGIC SYMBOL ± 74ALS158

2

3

5

6

11

10

14

13

2

3

5

6

11

10

14

13

I0a

I1a

I0b

I1b

I0c

I1c

I0d

I1d

I0a

I1a

I0b

I1b

I0c

I1c

I0d

I1d

1

S

1

S

15

E

15

E

Ya

Yb

Yc

Yd

Ya

Yb

Yc

Yd

VCC = Pin 16

VCC = Pin 16

4

7

9

12

4

7

9

12

GND = Pin 8

SC00053

GND = Pin 8

SC00054

1991 Feb 08

2

853±1129 01670

Philips Semiconductors	Product specification
Data selector/multiplexer	74ALS157/74ALS158

IEC/IEEE SYMBOL ± 74ALS157											IEC/IEEE SYMBOL ± 74ALS158
	1											1
			G1											G1
15											15
			EN											EN
	2					MUX						2					MUX
		1						4					1						4
3												3
		1											1
	5							7				5							7
	6											6
	11							9				11							9
	10											10
	14							12				14							12
13									SC00055		13									SC00056

LOGIC DIAGRAM ± 74ALS157

E	I0a	I1a	I0b	I1b	I0c	I1c	I0d	I0d	S
15	2	3	5	6	11	10	14	13	1
		4		7		9		12
		Ya		Yb		Yc		Yd
VCC = Pin 16
GND = Pin 8									SC00057

FUNCTION TABLE ± 74ALS157

				INPUTS				OUTPUTS
				S		I0n	I1n	Yn
		E
	H			X		X	X	L
		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

LOGIC DIAGRAM ± 74ALS158

E	I0a	I1a	I0b	I1b	I0c	I1c	I0d	I0d	S
15	2	3	5	6	11	10	14	13	1

	4		7		9		12
Ya		Yb		Yc		Yd

VCC = Pin 16
GND = Pin 8	SC00058

FUNCTION TABLE ± 74ALS158

				INPUTS				OUTPUTS
				S		I0n	I1n
		E							Yn
	H			X		X	X		H
		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

1991 Feb 08

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