Philips N74ALS257N, N74ALS258DB, N74ALS258N, N74ALS258D, N74ALS257D Datasheet

INTEGRATED CIRCUITS

74ALS257/74ALS258

Data selector/multiplexer

Product specification	1991 Feb 08
IC05 Data Handbook

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Philips Semiconductors	Product specification
Data selector/multiplexer	74ALS257/74ALS258

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

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 (Yn).

		TYPICAL	TYPICAL
	TYPE		SUPPLY CURRENT
		PROPAGATION DELAY
			(TOTAL)
	74ALS257	7.0ns	7mA
	74ALS258	7.0ns	7mA

ORDERING INFORMATION

		ORDER CODE
			DRAWING
	DESCRIPTION	COMMERCIAL RANGE
		VCC = 5V ±10%,	NUMBER
		Tamb = 0°C to +70°C
	16-pin plastic DIP	74ALS257N, 74ALS258	SOT38-4
	16-pin plastic SO	74ALS257D, 74ALS258D	SOT109-1
	16-pin plastic SSOP	74ALS257DB, 74ALS258DB	SOT338-1
	Type II

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

OE

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 ± 74ALS257

PIN CONFIGURATION ± 74ALS258

S

S

1

16

VCC

1

16

VCC

I0a

I0a

2

15

OE

2

15

OE

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

SF00673

SC00079

1991 Feb 08

2

853±1130 01670

Philips Semiconductors	Product specification
Data selector/multiplexer	74ALS257/74ALS258

LOGIC SYMBOL ± 74ALS257																									LOGIC SYMBOL ± 74ALS258
			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			OE						Ya		Yb		Yc		Yd										15			OE						Ya		Yb		Yc		Yd
VCC = Pin 16							4				7		9		12										VCC = Pin 16							4				7		9		12
GND = Pin 8																							SF00674		GND = Pin 8																							SC00080
IEC/IEEE SYMBOL ± 74ALS257																									IEC/IEEE SYMBOL ± 74ALS258
			15																									15
							EN																									EN
			1																									1
							G1																									G1
			2								MUX																	2								MUX
							1													4												1													4
			3																									3
						1																									1
			5																	7								5																	7
			6																									6
			10																	9								10																	9
			11																									11
			13																	12								13																	12
			14																				SF00675					14																				SC00081

LOGIC DIAGRAM ± 74ALS257

OE	I0a	I1a	I0b	I1b		I0c	I1c	I0d	I1d	S
15	2	3		5	6	11	10	14	13	1
		4		7			9		12
VCC = Pin 16		Ya		Yb			Yc		Yd
GND = Pin 8										SC00082

LOGIC DIAGRAM ± 74ALS258

OE	I0a	I1a	I0b	I1b		I0c	I1c	I0d	I1d	S
15	2	3		5	6	11	10	14	13	1
		4		7			9		12
VCC = Pin 16		Ya		Yb			Yc		Yd
GND = Pin 8										SC00083

1991 Feb 08

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Philips Semiconductors	Product specification
Data selector/multiplexer	74ALS257/74ALS258

FUNCTION TABLE ± 74ALS257

					INPUTS				OUTPUT
					S		I0n	I1n	Yn
		OE
		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 ªoffº state

FUNCTION TABLE ± 74ALS258

					INPUTS				OUTPUT
					S		I0n	I1n
		OE								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 ªoffº 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
VCC	Supply voltage	±0.5 to +7.0	V
VIN	Input voltage	±0.5 to +7.0	V
IIN	Input current	±30 to +5	mA
VOUT	Voltage applied to output in High output state	±0.5 to VCC	V
IOUT	Current applied to output in Low output state	48	mA
Tamb	Operating free-air temperature range	0 to +70	°C
Tstg	Storage temperature range	±65 to +150	°C

RECOMMENDED OPERATING CONDITIONS

	SYMBOL	PARAMETER		LIMITS		UNIT
			MIN	NOM	MAX
	VCC	Supply voltage	4.5	5.0	5.5	V
	VIH	High-level input voltage	2.0			V
	VIL	Low-level input voltage			0.8	V
	IIK	Input clamp current			±18	mA
	IOH	High-level output current			±2.6	mA
	IOL	Low-level output current			24	mA
	Tamb	Operating free-air temperature range	0		+70	°C

1991 Feb 08

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