Motorola MC74HC251D, MC74HC251N Datasheet

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SEMICONDUCTOR TECHNICAL DATA

1

REV 6

 Motorola, Inc. 1995

10/95

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High–Performance Silicon–Gate CMOS

The MC54/74HC251 is identical in pinout to the LS251. The device inputs
are compatible with standard CMOS outputs; with pullup resistors, they are
compatible with LSTTL outputs.

This device selects one of the eight binary Data Inputs, as determined by
the Address Inputs. The Output Enable pin must be a low level for the
selected data to appear at the outputs. If Output Enable is high, both the Y
and the Y

outputs are in the high–impedance state. This 3–state feature

allows the HC251 to be used in bus–oriented systems.

The HC251 is similar i n function t o the HC151 which does not have
3–state outputs.

• Output Drive Capability: 10 LSTTL Loads

• Outputs Directly Interface to CMOS, NMOS, and TTL

• Operating Voltage Range: 2 to 6 V

• Low Input Current: 1 µA

• High Noise Immunity Characteristic of CMOS Devices

• In Compliance with the Requirements Defined by JEDEC Standard

No. 7A

• Chip Complexity: 134 FETs or 33.5 Equivalent Gates

LOGIC DIAGRAM

D0
D1
D2
D3
D4
D5
D6
D7

A0
A1
A2

OUTPUT ENABLE

Y

Y

DATA

OUTPUTS

DATA

INPUTS

ADDRESS

INPUTS

5

6

4
3
2

1
15
14
13
12

11
10

9

7

PIN 16 = V

CC

PIN 8 = GND



PIN ASSIGNMENT

FUNCTION TABLE

Inputs Outputs

Output

A2 A1 A0 Enable Y Y

X X X H Z Z
L L L L D0 D0
L L H L D1 D1
L H L L D2 D2
L H H L D3 D3
H L L L D4 D4
H L H L D5 D5
H H L L D6 D6
H H H L D7 D7

Z = high impedance
D0, D1, …, D7 = the level of the respective

D input.

13

14

15

16

9

10

11

125

4

3

2

1

8

7

6

D7

D6

D5

D4

V

CC

A2

A1

A0

D0

D1

D2

D3

GND

OUTPUT

ENABLE

Y

Y

D SUFFIX

SOIC PACKAGE

CASE 751B–05

N SUFFIX

PLASTIC PACKAGE

CASE 648–08

ORDERING INFORMATION

MC54HCXXXJ
MC74HCXXXN
MC74HCXXXD

Ceramic
Plastic
SOIC

1

16

1

16

J SUFFIX

CERAMIC PACKAGE

CASE 620–10

1

16

MC54/74HC251

MOTOROLA High–Speed CMOS Logic Data

DL129 — Rev 6

2

MAXIMUM RATINGS*

Symbol

Parameter

Value

Unit

V

CC

DC Supply Voltage (Referenced to GND)

– 0.5 to + 7.0

V

V

in

DC Input Voltage (Referenced to GND)

– 1.5 to VCC + 1.5

V

V

out

DC Output Voltage (Referenced to GND)

– 0.5 to VCC + 0.5

V

I

in

DC Input Current, per Pin

± 25

mA

I

out

DC Output Current, per Pin

± 50

mA

I

CC

DC Supply Current, VCC and GND Pins

± 75

mA

P

D

Power Dissipation in Still Air,Plastic or Ceramic DIP†

SOIC Package†

750
500

mW

T

stg

Storage Temperature

– 65 to + 150

_

C

T

L

Lead Temperature, 1 mm from Case for 10 Seconds

(Plastic DIP or SOIC Package)

(Ceramic DIP)

260
300

_

C

*Maximum Ratings are those values beyond which damage to the device may occur.

Functional operation should be restricted to the Recommended Operating Conditions.

†Derating — Plastic DIP: – 10 mW/_C from 65_ to 125_C

Ceramic DIP: – 10 mW/_C from 100_ to 125_C
SOIC Package: – 7 mW/_C from 65_ to 125_C

For high frequency or heavy load considerations, see Chapter 2 of the Motorola High–Speed CMOS Data Book (DL129/D).

RECOMMENDED OPERATING CONDITIONS

Symbol

Parameter

Min

Max

Unit

V

CC

DC Supply Voltage (Referenced to GND)

2.0

6.0

V

Vin, V

out

DC Input Voltage, Output Voltage (Referenced to GND)

0

V

CC

V

T

A

Operating Temperature, All Package Types

– 55

+ 125

_

C

tr, t

f

Input Rise and Fall Time VCC = 2.0 V

(Figure 1) VCC = 4.5 V

VCC = 6.0 V

0
0
0

1000

500
400

ns

DC ELECTRICAL CHARACTERISTICS (Voltages Referenced to GND)

Guaranteed Limit

Symbol

Parameter

Test Conditions

V

CC
V

– 55 to

25_C

v

85_Cv 125_C

Unit

V

IH

Minimum High–Level Input
Voltage

V

out

= 0.1 V or VCC – 0.1 V

|I

out

| v 20 µA

2.0

4.5

6.0

1.5

3.15

4.2

1.5

3.15

4.2

1.5

3.15

4.2

V

V

IL

Maximum Low–Level Input
Voltage

V

out

= 0.1 V or VCC – 0.1 V

|I

out

| v 20 µA

2.0

4.5

6.0

0.3

0.9

1.2

0.3

0.9

1.2

0.3

0.9

1.2

V

V

OH

Minimum High–Level Output
Voltage

Vin = VIH or V

IL

|I

out

| v 20 µA

2.0

4.5

6.0

1.9

4.4

5.9

1.9

4.4

5.9

1.9

4.4

5.9

V

Vin = VIH or VIL|I

out

| v 4.0 mA

|I

out

| v 5.2 mA

4.5

6.0

3.98

5.48

3.84

5.34

3.70

5.20

V

OL

Maximum Low–Level Output
Voltage

Vin = VIH or V

IL

|I

out

| v 20 µA

2.0

4.5

6.0

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

0.1

V

Vin = VIH or VIL|I

out

| v 4.0 mA

|I

out

| v 5.2 mA

4.5

6.0

0.26

0.26

0.33

0.33

0.40

0.40

I

in

Maximum Input Leakage Current

Vin = VCC or GND

6.0

± 0.1

± 1.0

± 1.0

µA

I

OZ

Maximum Three–State
Leakage Current

Output in High–Impedance State
Vin = VIL or V

IH

V

out

= VCC or GND

6.0

± 0.5

± 5.0

± 10

µA

I

CC

Maximum Quiescent Supply
Current (per Package)

Vin = VCC or GND
I

out

= 0 µA

6.0

8

80

160

µA

NOTE: Information on typical parametric values can be found in Chapter 2 of the Motorola High–Speed CMOS Data Book (DL129/D).

This device contains protection
circuitry to guard against damage
due to high static voltages or electric
fields. However, precautions must
be taken to avoid applications of any
voltage higher than maximum rated
voltages to this high–impedance cir­cuit. For proper operation, Vin and
V

out

should be constrained to the

range GND v (Vin or V

out

) v VCC.

Unused inputs must always be
tied to an appropriate logic voltage
level (e.g., either GND or VCC).
Unused outputs must be left open.

MC54/74HC251

High–Speed CMOS Logic Data
DL129 — Rev 6

3 MOTOROLA

AC ELECTRICAL CHARACTERISTICS (C

L

= 50 pF, Input tr = tf = 6 ns)

Guaranteed Limit

Symbol

Parameter

V

CC
V

– 55 to

25_C

v

85_Cv 125_C

Unit

t

PLH

,

t

PHL

Maximum Propagation Delay, Input D to Output Y or Y

(Figures 1, 2 and 5)

2.0

4.5

6.0

185

37
31

230

46
39

280

56
48

ns

t

PLH

,

t

PHL

Maximum Propagation Delay, Input A to Output Y or Y

(Figures 3 and 5)

2.0

4.5

6.0

205

41
35

255

51
43

310

62
53

ns

t

PLZ

,

t

PHZ

Maximum Propagation Delay, Output Enable to Output Y

(Figures 4 and 6)

2.0

4.5

6.0

195

39
33

245

49
42

295

59
50

ns

t

PZL

,

t

PZH

Maximum Propagation Delay, Output Enable to Output Y

(Figures 4 and 6)

2.0

4.5

6.0

145

29
25

180

36
31

220

44
38

ns

t

PLZ

,

t

PHZ

Maximum Propagation Delay, Output Enable to Output Y

(Figures 4 and 6)

2.0

4.5

6.0

220

44
37

275

55
47

330

66
56

ns

t

PZL

,

t

PZH

Maximum Propagation Delay, Output Enable to Output Y

(Figures 4 and 6)

2.0

4.5

6.0

150

30
26

190

38
33

225

45
38

ns

t

TLH

,

t

THL

Maximum Output Transition Time, Any Output

(Figures 1 and 5)

2.0

4.5

6.0

75
15
13

95
19
16

110

22
19

ns

C

in

Maximum Input Capacitance

—

10

10

10

pF

C

out

Maximum Three–State Output Capacitance
(Output in High–Impedance

State)

—

15

15

15

pF

NOTES:

1. For propagation delays with loads other than 50 pF, see Chapter 2 of the Motorola High–Speed CMOS Data Book (DL129/D).

2. Information on typical parametric values can be found in Chapter 2 of the Motorola High–Speed CMOS Data Book (DL129/D).

Typical @ 25°C, VCC = 5.0 V

C

PD

Power Dissipation Capacitance (Per Package)*

36

pF

*Used to determine the no–load dynamic power consumption: PD = CPD V

CC

2

f + ICC VCC. For load considerations, see Chapter 2 of the

Motorola High–Speed CMOS Data Book (DL129/D).

PIN DESCRIPTIONS

INPUTS
D0, D1, …, D7 (Pins 4, 3, 2, 1, 15, 14, 13, 12)

Data inputs. Data on one of these eight binary inputs may

be selected to appear on the output.

CONTROL INPUTS
A0, A1, A2 (Pins 11, 10, 9)

Address inputs. The data on these pins are the binary ad-

dress of the selected input (see the Function Table).

Output Enable (Pin 7)

Output Enable. This input pin must be at a low level for the
selected data to appear at the outputs. If the Output Enable
pin is high, both the Y and Y

outputs are taken to the high–

impedance state.

OUTPUTS
Y, Y

(Pins 5, 6)

Data outputs. The selected data is presented at these pins
in both true (Y output) and complemented (Y

output) forms.