NSC DM54LS42J-883 Datasheet

TL/F/6365

54LS42/DM54LS42/DM74LS42 BCD/Decimal Decoders

June 1989

54LS42/DM54LS42/DM74LS42 BCD/Decimal Decoders

General Description

These BCD-to-decimal decoders consist of eight inverters
and ten, four-input NAND gates. The inverters are connect­ed in pairs to make BCD input data available for decoding
by the NAND gates. Full decoding of input logic ensures
that all outputs remain off for all invalid (10 –15) input condi­tions.

Features

Y

Diode clamped inputs

Y

Also for applications as 4-line-to-16-line decoders; 3­line-to-8-line decoders

Y

All outputs are high for invalid input conditions

Y

Alternate Military/Aerospace device (54LS42) is avail­able. Contact a National Semiconductor Sales Office/
Distributor for specifications.

Connection Diagram

Dual-In-Line Package

TL/F/6365– 1

Order Number 54LS42DMQB, 54LS42FMQB,

DM54LS42J, DM54LS42W, DM74LS42M or DM74LS42N

See NS Package Number J16A, M16A, N16E or W16A

Function Table

No.

BCD Inputs Decimal Outputs

DCBA0123456789

0 L L L L LHHHHHHHHH
1 L L L HHL HHHHHHHH
2 L LHL HHL HHHHHHH
3 L LHHHHHL HHHHHH
4 LH L L HHHHL HHHHH

5 LH LHHHHHHL HHHH
6 LHHLHHHHHHLHHH
7 LHHHHHHHHHH LHH
8 H L L L HHHHHHHHL H
9 H L LHHHHHHHHHHL

I

HL HLHHHHHHHHHH

N

HL HHHHHHHHHHHH

V

HHL LHHHHHHHHHH

A

HHL HHHHHHHHHHH

L

HHHL HHHHHHHHHH

I

HHHHHHHHHHHHHH

D

HeHigh Level
L

e

Low Level

Logic Diagram

TL/F/6365– 2

C

1995 National Semiconductor Corporation RRD-B30M105/Printed in U. S. A.

Absolute Maximum Ratings (Note)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.

Supply Voltage 7V

Input Voltage 7V

Operating Free Air Temperature Range

DM54LS and 54LS

b

55§Ctoa125§C

DM74LS 0

§

Ctoa70§C

Storage Temperature Range

b

65§Ctoa150§C

Note:

The ‘‘Absolute Maximum Ratings’’ are those values
beyond which the safety of the device cannot be guaran­teed. The device should not be operated at these limits. The
parametric values defined in the ‘‘Electrical Characteristics’’
table are not guaranteed at the absolute maximum ratings.
The ‘‘Recommended Operating Conditions’’ table will define
the conditions for actual device operation.

Recommended Operating Conditions

Symbol Parameter

DM54LS42 DM74LS42

Units

Min Nom Max Min Nom Max

V

CC

Supply Voltage 4.5 5 5.5 4.75 5 5.25 V

V

IH

High Level Input Voltage 2 2 V

V

IL

Low Level Input Voltage 0.7 0.8 V

I

OH

High Level Output Current

b

0.4

b

0.4 mA

I

OL

Low Level Output Current 4 8 mA

T

A

Free Air Operating Temperature

b

55 125 0 70

§

C

Electrical Characteristics over recommended operating free air temperature range (unless otherwise noted)

Symbol Parameter Conditions Min

Typ

Max Units

(Note 1)

V

I

Input Clamp Voltage V

CC

e

Min, I

I

eb

18 mA

b

1.5 V

V

OH

High Level Output V

CC

e

Min, I

OH

e

Max DM54 2.5 3.4

V

Voltage V

IL

e

Max, V

IH

e

Min

DM74 2.7 3.4

V

OL

Low Level Output V

CC

e

Min, I

OL

e

Max DM54 0.25 0.4

Voltage V

IL

e

Max, V

IH

e

Min

DM74 0.35 0.5 V

I

OL

e

4 mA, V

CC

e

Min DM74 0.25 0.4

I

I

Input Current@Max V

CC

e

Max, V

I

e

7V

0.1 mA

Input Voltage

I

IH

High Level Input Current V

CC

e

Max, V

I

e

2.7V 20 mA

I

IL

Low Level Input Current V

CC

e

Max, V

I

e

0.4V

b

0.4 mA

I

OS

Short Circuit V

CC

e

Max DM54

b

20

b

100

mA

Output Current (Note 2)

DM74

b

20

b

100

I

CC

Supply Current V

CC

e

Max (Note 3) 7 13 mA

Note 1: All typicals are at V

CC

e

5V, T

A

e

25§C.

Note 2: Not more than one output should be shorted at a time, and the duration should not exceed one second.

Note 3: I

CC

is measured with all outputs open and all inputs grounded.

2