Texas Instruments CD74HCT251M96, CD74HCT251M, CD74HCT251E, CD74HC251M96, CD74HC251M Datasheet

Data sheet acquired from Harris Semiconductor SCHS169

November 1997

CD74HC251,

CD74HCT251

High Speed CMOS Logic

8-Input Multiplexer; Three-State

Features

Description

•

Selects One of Eight Binary Data Inputs

The Harris CD74HC251 and CD74HCT251 are 8-channel

[ /Title

•

Three-State Output Capability

digital multiplexers with three-state outputs, fabricated with

high-speed silicon-gate CMOS technology. Together with the

(CD74

•

True and Complement Outputs

low power consumption of standard CMOS integrated cir-

HC251

•

Typical (Data to Output) Propagation Delay of 14ns at

cuits, they possess the ability to drive 10 LSTTL loads. The

,

three-state feature makes them ideally suited for interfacing

V

CC

= 5V, C

L

= 15pF, T = 25oC

with bus lines in a bus-oriented system.

CD74

A

•

Fanout (Over Temperature Range)

HCT25

This multiplexer features both true (Y) and complement (Y)

- Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads

outputs as well as an output enable (OE) input. The OE must

1)

-

Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads

be at a low logic level to enable this device. When the

OE

/Sub-

•

Wide Operating Temperature Range . . . -55oC to 125oC

input is high, both outputs are in the high-impedance state.

When enabled, address information on the data select inputs

ject

• Balanced Propagation Delay and Transition Times

determines which data input is routed to the Y and Y out-

(High

•

Significant Power Reduction Compared to LSTTL

puts. The CD74HCT251 logic family is speed, function, and

Speed

pin-compatible with the standard 74LS251.

CMOS

Logic ICs

• Alternate Source is Philips

Ordering Information

Logic

-

HC Types

8-Input

PKG.

Multi-

- 2V to 6V Operation

TEMP. RANGE (oC)

PART NUMBER

PACKAGE

NO.

plexer;

- High Noise Immunity: NIL = 30%, NIH = 30% of VCC

CD74HC251E

-55 to 125

16 Ld PDIP

E16.3

Three-

at VCC = 5V

• HCT Types

CD74HCT251E

-55 to 125

16 Ld PDIP

E16.3

-

4.5V to 5.5V Operation

CD74HC251M

-55 to 125

16 Ld SOIC

M16.15

- Direct LSTTL Input Logic Compatibility,

CD74HCT251M

-55 to 125

16 Ld SOIC

M16.15

VIL= 0.8V (Max), VIH = 2V (Min)

- CMOS Input Compatibility, Il ≤ 1μA at VOL, VOH

NOTES:

1. When ordering, use the entire part number. Add the suffix 96 to

obtain the variant in the tape and reel.

2. Wafer or die for this part number is available which meets all elec-

trical specifications. Please contact your local sales office or

Harris customer service for ordering information.

Pinout

CD74HC251, CD74HCT251

		(PDIP, SOIC)
		TOP VIEW
I3	1	16	VCC
I2	2	15	I4
I1	3	14	I5
I0	4	13	I6

Y

5

12

I7

Y

6

11 S0

OE	7	10	S1
GND	8	9	S2

CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.	File Number 1489.1

Copyright © Harris Corporation 1997

1

CD74HC251, CD74HCT251

Functional Diagram

OE

7

4

I0

3

I1

2

I2

1

CHANNEL I3 INPUTS I4 15

	14
	I5	5
	13	Y
	I6	OUTPUTS
	12
		6
	I7	Y

11

S0

10

DATA S1

SELECT 9 S2

TRUTH TABLE

		INPUTS						OUTPUT
	SELECT			OUTPUT
S2	S1		S0	CONTROL			Y
					OE					Y
X	X		X	H			Z			Z
L	L		L	L			I0		I0
L	L		H	L			I1		I1
L	H		L	L			I2		I2
L	H		H	L			I3		I3
H	L		L	L			I4		I4
H	L		H	L			I5		I5
H	H		L	L			I6		I6
H	H		H	L			I7		I7

NOTE: H = High Voltage Level, L = Low Voltage Level, X = Don’t Care, Z = High Impedance (Off), I0, I1...I7 = the level of the respective input.

2

CD74HC251, CD74HCT251

Absolute Maximum Ratings

DC Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . .	-0.5V to 7V
DC Input Diode Current, IIK	±20mA
For VI < -0.5V or VI > VCC + 0.5V . . . . . . . . . . . . . . . . . .
DC Output Diode Current, IOK	±20mA
For VO < -0.5V or VO > VCC + 0.5V . . . . . . . . . . . . . . . .
DC Drain Current, per Output, IO	±25mA
For -0.5V < VO < VCC +0.5V . . . . . . . . . . . . . . . . . . . . . .
DC Output Source or Sink Current per Output Pin, IO	±25mA
For VO > -0.5V or VO < VCC + 0.5V . . . . . . . . . . . . . . . .
DC VCC or Ground Current, ICC . . . . . . . . . . . . . . . . . . . . .	. . . .±50mA

Thermal Information
Thermal Resistance (Typical, Note 3)	θJA (oC/W)
PDIP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 90
SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 160
Maximum Junction Temperature . . . . . . . . . . . . . . . .	. . . . . . . 150oC
Maximum Storage Temperature Range . . . . . . . . . .	-65oC to 150oC
Maximum Lead Temperature (Soldering 10s) . . . . . .	. . . . . . . 300oC
(SOIC - Lead Tips Only)

Operating Conditions

Temperature Range (TA) . . . . . . . . . . . . . . . . . . . . . -55oC to 125oC Supply Voltage Range, VCC

HC Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2V to 6V HCT Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4.5V to 5.5V

DC Input or Output Voltage, VI, VO . . . . . . . . . . . . . . . . . 0V to VCC Input Rise and Fall Time

2V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000ns (Max) 4.5V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500ns (Max)

6V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400ns (Max)

CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

NOTE:

3. θJA is measured with the component mounted on an evaluation PC board in free air.

DC Electrical Specifications

		TEST				25oC		-40oC TO 85oC		-55oC TO 125oC
		CONDITIONS		VCC
PARAMETER	SYMBOL	VI (V)	IO (mA)	(V)	MIN	TYP	MAX	MIN	MAX	MIN	MAX	UNITS
HC TYPES
High Level Input	VIH	-	-	2	1.5	-	-	1.5	-	1.5	-	V
Voltage
				4.5	3.15	-	-	3.15	-	3.15	-	V
				6	4.2	-	-	4.2	-	4.2	-	V
Low Level Input	VIL	-	-	2	-	-	0.5	-	0.5	-	0.5	V
Voltage
				4.5	-	-	1.35	-	1.35	-	1.35	V
				6	-	-	1.8	-	1.8	-	1.8	V
High Level Output	VOH	VIH or VIL	-0.02	2	1.9	-	-	1.9	-	1.9	-	V
Voltage
			-0.02	4.5	4.4	-	-	4.4	-	4.4	-	V
CMOS Loads
			-0.02	6	5.9	-	-	5.9	-	5.9	-	V
High Level Output			-	-	-	-	-	-	-	-	-	V
Voltage
			-4	4.5	3.98	-	-	3.84	-	3.7	-	V
TTL Loads
			-5.2	6	5.48	-	-	5.34	-	5.2	-	V
Low Level Output	VOL	VIH or VIL	0.02	2	-	-	0.1	-	0.1	-	0.1	V
Voltage
			0.02	4.5	-	-	0.1	-	0.1	-	0.1	V
CMOS Loads
			0.02	6	-	-	0.1	-	0.1	-	0.1	V
Low Level Output			-	-	-	-	-	-	-	-	-	V
Voltage
			4	4.5	-	-	0.26	-	0.33	-	0.4	V
TTL Loads
			5.2	6	-	-	0.26	-	0.33	-	0.4	V

3